JP2005029885A - Thin film forming method, thin film forming apparatus, and semiconductor device - Google Patents

Abstract

A film having excellent film formation controllability and high packing density can be formed.
A reactor 10 for depositing a first organic precursor material 4 as a host material is assumed to employ a vacuum deposition method. The second organic precursor material 6 as the guest material is vaporized in the vaporizer 80 and mixed with the inert carrier gas 7 supplied from the gas purifier 94, and this mixed vapor 8 is passed through the pipe 87 to the reactor 10. Introduce in. A mass flow controller 90 is attached on the path of the pipe 89. The concentration of doping is controlled by controlling the amount of the second organic precursor material 6 introduced into the reactor 10 by the mass flow controller 90. A host material is attached to the substrate W by a vacuum vapor deposition method capable of forming a film with high speed and high accuracy, and a guest material is attached to the substrate W by an OVPD method having excellent concentration controllability. The host material can enjoy the advantages of the vacuum deposition method, and the guest material can enjoy the advantages of the OVPD method.
[Selection] Figure 1

Description

  The present invention relates to a thin film forming method, a thin film forming apparatus, and a semiconductor device. More specifically, the present invention relates to a deposition technique for attaching an evaporation material to a member to be deposited, which is suitable for use in manufacturing, for example, an organic electroluminescent element (organic EL element: EL is an abbreviation for electroluminescence).

  In recent years, attention has been paid to those using organic EL elements as flat display devices. Since a display device (organic EL display) using an organic EL element is a self-luminous display that does not require a backlight, it has advantages such as a wide viewing angle and low power consumption.

  An organic EL element used for such an organic EL display generally has a structure in which an organic layer (organic EL layer) made of an organic material is sandwiched between electrodes (anode and cathode) from above and below. Then, by applying a positive voltage to the anode and a negative voltage to the cathode, respectively, holes are injected from the anode into the organic layer, while electrons are injected from the cathode, thereby causing holes in the organic layer. The mechanism is such that electrons recombine and emit light.

  The organic layer of the organic EL element usually has a laminated structure of 3 to 5 layers such as a hole injection layer, a hole transport layer, a light emitting layer, and a charge injection layer. The organic material forming each layer has low water resistance and cannot use a wet process. Therefore, for example, when forming an organic layer based on both a low molecule and a polymer, the rotary evaporation method is employed. Polymer-based devices have the general advantage that they can be manufactured simply and inexpensively by the rotary evaporation method.

  On the other hand, as shown in the schematic configuration diagram of FIG. 9, the low molecular device is formed by sequentially depositing each layer on an element substrate (usually a glass substrate) of an organic electroluminescent element by a vacuum deposition method using a vacuum thin film forming technique. The desired laminated structure is obtained by forming. In this vacuum deposition method, the inside of the film forming chamber 211 is set to a relatively high state of about 10 ^ -3 ("^" indicates power) to 10 ^ -4 Pascal (Pa), for example, in such a vacuum. , The heating source 220 using resistance heating or the like is controlled to evaporate the organic raw material 204 in the crucible 214, and the substrate plate W is disposed at a position facing the evaporation source 230 of the holding base 215. In this process, the evaporated organic substance 204a is deposited to form a thin film.

  The vacuum evaporation method is usually more expensive than the rotary evaporation method. However, since a thin film is formed at a high degree of vacuum, a thin film with a high packing density (packing density) can be formed, and an organic EL element with few pinholes is produced. Has the advantage of being able to. In addition, high-speed production can be realized with a relatively simple apparatus configuration, and productivity is high.

  When forming an organic film, the guest (Guest) is different from the HOST material, which is the main material, in order to improve the characteristics of the organic film, such as improving the luminous efficiency, improving the lifetime, or stabilizing the thin film state. A technique of doping a material as an additive material is used. Here, when doping is performed in a vacuum deposition method, a technique called co-deposition in which a host material and a guest material are simultaneously vacuum deposited is employed.

  However, organic doping by vacuum deposition has a problem that the controllability of the doping concentration is poor. The main reason is that the doping concentration controllability largely depends on the resolution of the film thickness meter because the doping concentration is converted based on the film formation rate measured by the film thickness meter 217 having a low resolution.

  For example, a method using a crystal resonator is widely used as a film thickness monitor during vapor deposition. The quartz vibrator vibrates at a constant frequency, but when a film formed by vapor deposition adheres to the quartz vibrator, the vibration frequency changes due to a mass change of the vibrator. By monitoring this change, the film thickness can be measured. However, since the rate measurement accuracy of a crystal vibration type film thickness meter generally used as a film thickness meter is at most about 0.1 mm / s, for example, a guest material for a host material having a film forming rate of 2 mm / s. In order to perform doping with an accuracy of 1 ± 0.1 vol%, it is necessary to perform the film formation rate accuracy of the guest material at 0.02 ± 0.002 vol%. However, as described above, the measurement accuracy with the crystal vibration type film thickness meter is insufficient.

  In addition, a method called rate control is adopted in which the vapor deposition rate of the organic material 204 evaporated from the evaporation source 230 is detected, and the evaporation amount of the organic material 204 from the evaporation source 230 is controlled based on the detection result. . Here, in this rate control, the evaporation amount of the organic material is controlled by adjusting the output of the heating source 220 as a heat source of the evaporation source 230.

  However, in general, an organic material used for manufacturing an organic EL element has poor thermal efficiency and a deposition temperature is relatively low. Therefore, when the amount of heat applied to the heating source 220 is changed, the heat of the heating source 220 is actually increased. It takes a long time for the change in the deposition rate to be transmitted to the organic material. Therefore, responsiveness (rate controllability) when controlling the deposition rate is poor, and it is difficult to stably control the film thickness of the organic material.

  For example, organic materials are powdery raw materials that are difficult to heat uniformly, and because the raw material container is placed in a vacuum atmosphere, it is difficult to heat or cool quickly, changing the heating temperature of the evaporation source. Since the rate of change of the evaporation rate at this time is slow, there is a disadvantage that the film formation rate is unstable. In addition, since the substrate W cannot be put in between the time when the deposition rate is changed and the time when the deposition rate is stabilized at a desired level, expensive organic materials are wasted in the meantime. Cause cost increase.

  On the other hand, a method using an organic vapor phase deposition (OVPD method) in which a vapor deposition method is applied to an organic thin film has been proposed. The OVPD method can control and co-deposit materials with significantly different vapor pressures. In addition to controlling the raw material heating temperature, the deposition film thickness can be controlled by controlling the flow rate of the vaporized organic material, and the flow rate control can be realized with high accuracy and high speed. Compared with the vacuum deposition method, the rate controllability and film thickness controllability are good. The same applies to the control of the doping amount of the guest material. As described above, the OVPD method ensures high temperature stability by sufficiently mixing high temperature inert gas and organic vapor in, for example, a mixing chamber to increase temperature uniformity, and controls a gas flow rate that is easy to control. Thus, a stable film forming speed can be realized.

  However, the OVPD method is performed near atmospheric pressure, and a film grown at or near atmospheric pressure is rough, and has a problem of having a non-uniform surface morphology due to vapor phase nucleation and diffusion-controlled growth processes. In addition, the OVPD method uses a large amount of gas for transporting raw materials, so the degree of vacuum in the film forming chamber is poor. For example, an organic film is formed in a low vacuum of several tens of pascals, so that the evaporation molecules are reduced in vacuum. Since the kinetic energy of the evaporated particles is lowered by colliding with the gas existing in the film, the particle diffusion on the film substrate becomes insufficient, making it difficult to obtain a dense film or presenting in a low vacuum When the gas to be entrained is entrained inside the film, the film becomes rough.

  As a technique for solving the above problem in the OVPD method, a low-pressure organic vapor deposition method (LPOVPD method) has been proposed in, for example, Patent Document 1. The technique described in Patent Document 1 uses, for example, an apparatus as shown in FIG. 10 (similar to FIG. 1 of Patent Document 1) to carry a source gas to a substrate using a carrier gas under reduced pressure. This is an organic film forming method in which gas is condensed to form a film. In addition, this is an organic thin film forming method in which the amount of each component of the multi-component thin film can be accurately and precisely controlled by introducing and simultaneously vapor-depositing organic materials having significantly different vapor pressures into the reaction tube. In this LPOVPD method, for example, in a relatively low vacuum of about several tens to several hundreds of pascals, an organic source gas evaporated by resistance heating or the like is mixed with an inert carrier gas, and the mixed gas is transported through a shower head. Then, an organic substance is deposited on the substrate and thinned.

JP-T-2001-523768

  For example, in FIG. 10, the crucible 14 contains a first organic precursor material and is disposed in a tube 36 near one end 20 of the reaction tube 12 to provide a regulated flow 30 of inert carrier gas to the tube. 36 is fed into the reaction chamber through which the vapor of the first organic precursor flows along the reaction tube 12 toward its discharge end. Further, the vapor of the second organic precursor 48 is carried as bubbles from the bubbler 46 in which the second organic precursor material 6 is accommodated into the reaction furnace 12 through the pipe 54. In this way, organic materials having different characteristics are formed on the substrate 58 by an organic thin film forming method capable of accurately and accurately controlling the amount of each component of the multicomponent thin film.

  However, in order to form an organic film having smooth surface properties by the LPOVPD method, it is necessary to avoid crystallization of the organic film and further growth of crystal grains. For this reason, the substrate temperature rise accompanying the transport of the high temperature source gas must be suppressed as much as possible, and the substrate temperature must be maintained near room temperature or at least below the crystallization temperature when forming the film. Therefore, in the LPOVPD method, it is difficult to control the substrate temperature, and a substrate holder having a complicated mechanism is required.

  In addition, the LPOVPD method is a low-vacuum process with a film forming pressure of several tens to several hundreds of pascals, so that a porous film with a low packing density (a lot of gaps) is easily formed by entraining a gas in the thin film. For this reason, there are many voids and pinholes, and there is a drawback that a film with low reliability is easily formed, such as low mechanical strength of the film, poor electrical characteristics, and low adhesion to the substrate.

  This invention is made | formed in view of the said situation, and it aims at providing the technique which is excellent in the film-forming controllability of a vapor deposition film, and can form a film | membrane with high packing density.

  That is, the thin film forming method according to the present invention is a method of forming a thin film on a substrate by attaching an evaporated material to the substrate, and supplying the first precursor material to the substrate by a vacuum deposition method. The second precursor material was supplied to the substrate by a vapor phase method.

  The thin film forming apparatus according to the present invention is an apparatus suitable for carrying out the thin film forming method according to the present invention, and a film forming furnace for supplying the first precursor material to the substrate by a vacuum evaporation method; And a vaporizer for vaporizing the second precursor material, and a pipe for introducing the second precursor material vaporized by the vaporizer into the film forming furnace.

  The invention described in the dependent claims defines further advantageous specific examples of the thin film forming method and apparatus according to the present invention.

  For example, the first precursor material and the second precursor material are, for example, those in which an organic thin film is deposited on a substrate by a reaction of a vapor precursor. Here, “reaction” means a chemical reaction in which a precursor reactant forms a well-defined reaction product, or alternatively it simply means a combination or mixture of precursor materials, or a precursor. It means when the material forms a donor-acceptor or guest-host relationship.

  The same material may be used as the first and second precursor materials. By doing so, the thin film formation of the predetermined substance can be performed simultaneously with the vacuum deposition method and the OVPD method. Further, the same material may be used as one of the first precursor material and the second precursor material, and a material different from the first precursor material may be used as the other of the second precursor material. Good. In this way, another material can be introduced (for example, doped) by the OVPD method while forming a thin film of the predetermined material simultaneously with the vacuum deposition method and the OVPD method.

  Further, the first substance may be used as one of the first and second precursor materials, and a substance different from the first substance may be used as the other of the first and second precursor materials. Good. This makes it possible to introduce (for example, dope) another substance at a high concentration by the vacuum deposition method and the OVPD method while forming a thin film of the predetermined material simultaneously with the vacuum deposition method and the OVPD method. .

  When introducing the second precursor material into the film forming furnace through the pipe, it is preferable to use an inert gas as a transport gas. In addition, when the second precursor material is introduced into the film forming furnace, the flow rate thereof may be controlled by providing a mass flow controller in a part of the piping, for example. Further, a monitoring unit for monitoring the degree of deposition of the precursor material on the substrate may be provided in the film forming furnace, and the gas flow rate control of the OVPD method may be performed with reference to the monitoring result. In this way, the introduction amount of the second precursor material can be managed with high accuracy. For example, the doping concentration of the second precursor material into the first precursor material can be adjusted with high accuracy, When the same material is used as each of the second precursor materials, the film thickness can be adjusted with high accuracy.

  The installation position and shape of the piping introduced from the vaporization apparatus into the film-forming furnace can be determined by attaching a combination or mixture of the first and second precursors to the substrate, or by applying chemical reactants of a plurality of precursors to the substrate. It may be determined in consideration of adhesion to the precursor, or formation of a precursor / donor or guest / host relationship with the precursor material.

  Further, in order to cope with a large substrate, an evaporation source having an opening container for accommodating the first precursor material and a heating mechanism is formed in a long shape to form a line-type evaporation source, and the vaporized first The leading end of the pipe for introducing the second precursor material into the film forming furnace is provided with a lead-out end for leading out the mixed gas containing the second precursor material in a long shape and substantially parallel to the longitudinal direction of the vapor deposition source. Good.

  Also, a moving mechanism that moves the evaporation source and the lead-out end relative to the substrate in a direction perpendicular to the longitudinal direction of the vapor deposition source, and a film thickness measurement that measures the film thickness of the precursor material attached to the substrate. And a moving speed control unit that controls the relative moving speed of the moving mechanism unit based on the measurement result of the film thickness measuring unit.

  In addition, a substrate to be deposited is mounted on a carrier and moved relative to a plurality of line-type evaporation sources to continuously deposit a plurality of precursor materials on a large-area substrate. It is good also as an apparatus structure.

  The semiconductor device according to the present invention has a structure with accurate doping concentration modulation. Such a structure is configured by manufacturing using the thin film forming apparatus according to the present invention.

  In the above configuration according to the present invention, the first precursor material is supplied to the substrate by the vacuum deposition method, and the second precursor material is supplied by the vapor phase method. In this way, the first precursor material can enjoy the advantages of the vacuum deposition method, and the second precursor material can enjoy the advantages of the vapor phase method.

  In this way, the first precursor material is attached to the substrate by a vacuum deposition method capable of forming a film with high speed and high accuracy, and the second precursor material is vacuum deposited by an OVPD method having excellent concentration controllability. It can be introduced into a film forming furnace to which the method is applied. Therefore, the first precursor material can enjoy the advantages of the vacuum deposition method, and the second precursor material can enjoy the advantages of the OVPD method.

  Thus, the concentration controllability of the second precursor material is excellent, and the packing density is high for the first and second precursor materials and the chemical reactants of the first and second precursor materials. High performance thin films can be formed on a substrate.

  Further, by using the same material as the first precursor material as the second precursor material, a thin film of this material is formed on a predetermined substrate by a vacuum deposition method, and at the same time supplementarily by the OVPD method. By depositing the same material, it is possible to have a film density equivalent to that of the vacuum vapor deposition method and to improve the film deposition stability.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic view showing a first embodiment of a semiconductor manufacturing apparatus to which a thin film forming apparatus according to the present invention is applied. In this semiconductor manufacturing apparatus 1, the mixed vapor 8 containing the second organic precursor material 6 is introduced from the vaporizer 80 side for applying the OVPD method into the reaction apparatus 10 to which the vacuum vapor deposition method is applied. It is configured. With such a configuration, for example, the host material as the first organic precursor material 4 is formed by the vacuum deposition method, and the guest (GEST) material as the second organic precursor material 6 is formed by the OVPD method. A film having excellent doping concentration controllability of the organic film and high packing density can be formed. This will be specifically described below.

  The reaction apparatus 10 includes a film forming chamber (reaction chamber) 11. The film forming chamber 11 is, for example, a cylinder having an appropriate size having a predetermined diameter and length. The film forming chamber 11 is made of a suitable material such as glass or quartz.

  The film forming chamber 11 has a crucible 14 as an example of an opening container in the lower part of the figure, and a substrate W as a vapor deposition member is held on the upper part of the crucible 14 (opening part 14a side) by a substrate holder (not shown). A substrate holding base 15 and a crystal film thickness meter 17 for measuring the film thicknesses of the first organic precursor material 4 and the second organic precursor material 6 deposited on the substrate W are provided.

  Around the crucible 14 placed in the film forming chamber 11, a heating source (not shown) for evaporating the first organic precursor material 4 as a vapor deposition material is provided, and the evaporation source is configured as a whole. It is like that. The heating source is, for example, a heater composed of a heating wire, and the temperature can be controlled by a temperature measuring device and a temperature controller (both not shown). The crucible 14 is made of a material having good thermal conductivity, such as carbon, titanium, and tantalum, and is a heat-resistant container for containing the first organic precursor material 4, and as a host deposition source material to be evaporated. The first organic precursor material 4 is accommodated. By controlling the temperature of the crucible 14, thermal decomposition or evaporation of the first organic precursor material 4 in the crucible 14 is given.

  The film thickness control for the first organic precursor material 4 is performed, for example, by measuring the deposition rate of the first organic precursor material 4 evaporated from the evaporation source (vacuum deposition source) 130 with the quartz film thickness meter 17 and A method called rate control may be employed in which the temperature of the evaporation source 130 is adjusted so that the deposition rate of the organic material monitored by the film thickness meter 17 is constant (see, for example, Japanese Patent Application No. 2003-1770 by the present applicant). ). In this rate control, the film thickness of the first organic precursor material 4 is controlled by adjusting the output of the heating source serving as the heat source of the evaporation source 130 to control the evaporation amount of the first organic precursor material 4. A predetermined value is set. In the configuration shown in the figure, since the second organic precursor material 6 is also deposited on the quartz film thickness meter 17, the film thickness including the second organic precursor material 6 is measured. In this case, the influence of the second organic precursor material 6 can be ignored.

  In the semiconductor manufacturing apparatus 1, the substrate W on which a thin film is deposited is typically selected from materials generally used when manufacturing semiconductors and optical devices. For example, such materials include glass, quartz, silicon, gallium arsenide and other III-V semiconductors, aluminum, gold and other noble and base metals, polymer films, silicon dioxide and silicon nitride, indium tin oxide, and the like. included. For high-quality optical thin films, it is preferable to use a substrate that causes a crystalline interaction with the deposited organic film to cause epitaxial growth. In order to achieve such epitaxial growth, it is necessary to coat the substrate with a nonpolar organic material having a crystal structure similar to the film to be deposited.

  Furthermore, when the organic thin film is vacuum deposited on the substrate W, it is preferable to control the temperature of the substrate W. This independent control of the temperature of the substrate W is achieved, for example, by bringing a temperature control block having a channel for circulating a substance such as water, gas, freon glycerin, and liquid nitrogen into contact with the substrate W. In this example, it can be realized by configuring the substrate holding base 15 as a temperature control block. The substrate W can also be heated by using a resistor or a radiation heater arranged near the substrate W.

  The substrate holding base 15 is attached to a substrate rotating mechanism unit 16 provided on the upper part of the film forming chamber 11 and is configured as a rotating sample holder as a whole, and the substrate W held on the substrate holding base 15 is The substrate holding base 15 is rotated integrally. That is, the reaction apparatus 10 can apply a rotary evaporation method.

  An exhaust pipe 19 for exhausting gas to the outside of the film forming chamber 11 is provided on one side wall (left side in the figure) of the film forming chamber 11, and an OVPD source is provided on the other side wall (left side in the figure). A pipe 87 extending from the vaporizer 80 side to the inside of the film forming chamber 11 is provided. The arrangement positional relationship between the exhaust pipe 19 and the pipe 87 is set to face each other with the substrate W and the crucible 14 interposed therebetween. By doing so, the second organic precursor material 6 contained in the mixed vapor 8 injected from the discharge end 87a and the first organic precursor material 4 from the crucible 14 are mixed exactly on the substrate W, and the substrate Co-deposited on W.

  In the example of the basic configuration shown in the figure, the position of the discharge end 87a of the pipe 87 is set near the evaporation source 130, and the material gas 4a of the first organic precursor material 4 emitted from the evaporation source 130. And the material gas 6a of the second organic precursor material 6 introduced through the pipe 87 are mixed and attached to the substrate W. Thereby, the second organic precursor material 6 is mixed as an additive material in the organic layer of the host material (matrix material) made of the first organic precursor material 4.

  However, such an arrangement is merely an example, and a discharge end 87a of a pipe 87 may be introduced into the film forming chamber 11 from the lower part of the film forming chamber 11, for example, as indicated by a dotted line in the drawing. Even in this case, it is preferable that the discharge end 87a is opposite to the exhaust pipe 19 with the evaporation source 130 interposed therebetween. Further, the position of the exhaust pipe 19 is not limited to the side surface of the film forming chamber 11, for example, as shown by the dotted line in the drawing, the upper portion of the film forming chamber 11 (through the drive shaft of the substrate rotating mechanism unit 16 in the example in the figure). May be provided. In any case, the material gas 4a of the first organic precursor material 4 emitted from the evaporation source 130 and the material gas 6a of the second organic precursor material 6 introduced through the pipe 87 are mixed and adhered to the substrate W. This is the same as the basic configuration shown in the figure.

  Further, the discharge end 87 a of the pipe 87 may be disposed in the vicinity of the substrate W. In this case, in the process in which the first organic precursor material 4 emitted from the evaporation source 130 reaches the substrate W as the material gas 4a and adheres to the substrate W, the mixed vapor 8 introduced through the pipe 87 is almost simultaneously. The second organic precursor material 6 is added to the substrate W, so that the second organic precursor material 6 is added to the organic layer of the host material (matrix material) made of the first organic precursor material 4 as an additive material. Mixed (doping).

  It cannot be generally said which arrangement is preferable. Differences in the chemical characteristics of the first organic precursor material 4 as the host material and the second organic precursor material 6 as the guest material, the vapor deposition or doping mechanism, and the performance of the resulting organic film, etc. It is good to decide in consideration of

  A trap, a vacuum pump, and a control throttle valve (not shown) are attached to the exhaust pipe 19 so that the raw material vapor chamber formed in the film forming chamber 11 becomes a pressure reducing system capable of exhausting and holding molecules other than the raw material under reduced pressure. I have to. Most of the organic vapor not deposited on the substrate W is condensed in a trap disposed upstream of the vacuum pump. The trap contains, for example, liquid nitrogen or neutral fluorocarbon oil. The throttle valve adjusts the pressure in the film forming chamber 11. A suitable pressure gauge is attached to the reactor (not shown) and electrical feedback is applied to the control throttle valve to maintain the desired pressure in the reactor.

  For example, the vacuum pump applies a pressure of about 10 ^ -3 to 10 ^ -2 Pascal (Pa) in the film forming chamber 11. For any combination of acceptor layer, donor layer, and single component layer, the actual pressure depends on the temperature required to evaporate the first organic precursor material 4, the first organic precursor material 4 and It is determined in consideration of the wall temperature that prevents condensation of the second organic precursor material 6 and the reaction region temperature gradient. The optimum choice of pressure is set according to the requirements of each deposited organic layer.

  The vaporizer 80 provided on the right side of the reactor 10 in the figure includes a heating furnace 82 and a heating mechanism 83 provided so as to surround the heating furnace 82. In the heating furnace 82, an internal furnace 84 that houses a crucible 85 as an example of an open container is provided. The crucible 85 placed in the internal furnace 84 contains the second organic precursor material 6 as a guest (GEST) deposition source material.

  The crucible 85 is heated or cooled substantially by the heating mechanism 83 surrounding the heating furnace 82 that houses the internal furnace 84. By controlling the temperature of the crucible 85, the second organic precursor material 6 in the crucible 85 is thermally decomposed or evaporated.

  A pipe 87 extending into the film forming chamber 11 of the reaction apparatus 10 is provided on one side wall (left side in the drawing) of the internal furnace 84, and a switching valve 86 is attached on the path of the pipe 87. In addition to the pipe 87, a pre-flow pipe 88 is attached to the switching valve 86. Until the flow rate of the mixed steam 8 is stabilized by setting the switching valve 86 to the piping 88 side, the exhaust is exhausted to the outside through the preliminary flow piping 88, and when the flow rate is stabilized, the switching valve 86 is switched to the piping 87 side. This makes it possible to control the doping amount with high accuracy.

  On the other side wall (right side in the figure) of the internal furnace 84, the second organic precursor is extended so as to extend to a gas purification device (inert gas supply unit) 94 as a carrier gas source provided outside the vaporizer 80. A pipe 89 for introducing a mixed vapor 8 of the material 6 and the inert carrier gas 7 is provided as a carrier gas supply pipe. On the path of the pipe 89, a mass flow controller 90, a pressure regulator 92, and a regulating valve 96, which form an OVPD gas flow rate control mechanism, are attached in series to the gas purification device 94 side.

  In the gas purifier 94, an inert carrier gas 7 such as argon (Ar), nitrogen (N2), helium, krypton, xenon, or neon is accommodated. Reducing gases such as hydrogen, ammonia and methane are also inert to many organic materials. The use of these reducing gases provides the added benefit of helping to burn unwanted excess reactants.

  All the pipes and containers from the pipe 87 through which the second organic precursor material 6 is introduced into the film forming chamber 11 to the mass flow controller 90 are temperature-controlled at a predetermined high temperature. There are various heating methods for temperature control, such as an air temperature chamber method installed in an oven, a method of circulating high-temperature oil, an RF heating method (Radio Frequency heating device: high frequency induction heating device), a lamp heating method, etc. Any of the schemes can be used. The heating mechanism 83 of this embodiment forms part of that.

  The inert carrier gas 7 is introduced into the pipe 89 from the gas purification device 94 and sequentially passes through the control valve 96, the pressure regulator 92, and the mass flow controller 90 constituting the flow rate control unit, and in the internal furnace 84 of the vaporizer 80. Sent to. Then, in the internal furnace 84, it is mixed with the guest vapor of the second organic precursor material 6 and introduced into the film forming chamber 11 via the pipe 87. The regulating valve 96 sends the regulated flow of the inert carrier gas 7 through the pipe 89 to the internal furnace 84. The switching valve 86 sends a regulated flow of the mixed vapor 8 of the second organic precursor material 6 and the inert carrier gas 7 to the film forming chamber 11 through the pipe 87. As a result, the vapor of the second organic precursor material 6 flows along the pipe 87 toward the discharge end 87 a in the film forming chamber 11. The discharge end 87a of the pipe 87 functions as an OVPD injector (gas nozzle; introduction end) itself.

  Here, since the reactor 10 applies the vacuum deposition method, the film deposition performance of the first organic precursor material 4 can enjoy the advantages of the vacuum deposition method. For example, the management of the substrate temperature during film formation does not need to be as accurate as the LPOVPD method. Therefore, the control of the substrate temperature is easy, and the substrate holding base 15 and the substrate holder having a simple mechanism can be used. In addition, since the vacuum deposition method forms a thin film with a relatively high degree of vacuum, it can form a thin film with a high packing density, has few voids and pinholes, and has a high mechanical strength of the film (for example, electrical properties). It is possible to form an organic film with high reliability such as good resistance) and strong adhesion to the substrate, whereby a high-performance organic EL element can be manufactured. In addition, a high-speed rate can be achieved with a relatively simple apparatus configuration, which increases productivity.

  On the other hand, regarding the poor controllability of the doping concentration in the organic doping by vacuum deposition, the mixed vapor 8 containing the second organic precursor material 6 is introduced into the film forming chamber 11 from the vaporizer 80 via the pipe 87. It can be improved by applying the OVPD method that employs a mechanism. In the OVPD method, the film thickness control can control the supply amount of the raw material by controlling the flow rate of the vaporized organic material in addition to the raw material heating temperature control, and this flow rate control can be realized with high accuracy and high speed. This is because rate controllability and film thickness controllability are better than those of the vacuum deposition method.

  In the present embodiment, the amount of the second organic precursor material 6 introduced into the film forming chamber 11 can be controlled by processing parameters such as the temperature and flow rate of the introduced gas and the temperature of the mixed vapor 8. The flow rate control can be realized by self-control by the mass flow controller 90 itself. For example, the inert carrier gas 7 whose pressure is controlled to a predetermined pressure by the pressure regulator 92 and whose flow rate is controlled with high accuracy by the mass flow controller 90 is supplied from the gas purifier 94 to the pipe 89. Then, the deposition raw material vapor obtained by vaporizing the second organic precursor material 6 in the internal furnace 84 is transported and supplied from the vaporizer 80 to the deposition chamber 11 together with the inert carrier gas 7 via the pipe 87.

  For example, the flow rate measurement accuracy of the mass flow controller 90 used in this embodiment is assumed to be ± 0.2% of full scale. In this case, if a full scale of 50 sccm (standard cc / min: flow rate per minute in the standard state) is used, the control accuracy of the flow rate flowing into the film forming chamber 11 is ± 0.1 sccm. Therefore, when OVPD vapor having a concentration of 50% of the second organic precursor material 6 is used, the accuracy of the amount of the second organic precursor material 6 flowing into the film forming chamber 11 becomes ± 0.05 sccm.

  That is, the second organic precursor material 6 can be controlled with an accuracy of ± 0.05 sccm / 50 sccm = ± 0.1%, and the doping control accuracy by vacuum deposition is 0.02 nm / s (± 0.01 nm / s). ), That is, the accuracy is improved by 500 times compared with ± 50% control.

  In addition, since the flow rate of OVPD vapor is as low as several tens sccm, the degree of vacuum during film formation can be maintained at a high vacuum of about 10 ^ -4 to 10 ^ -2 Pascals. Can be formed.

  Thus, according to the configuration of the present embodiment, the flow of the second organic precursor material 6 can be accurately managed by using the mass flow controller 90. Therefore, the second organic precursor material 6 as the guest material is sent into the film forming chamber 11 and a material having a composition and characteristics different from those of the first organic precursor material 4 as the host material are attached to the substrate W. it can.

  Various materials can be used for the first organic precursor material 4 and the second organic precursor material 6. For example, organic substances listed in Patent Document 1 (for example, Table 1 and other descriptions) can be applied. In any case, a necessary precursor material can be supplied to the first organic precursor material 4 and the second organic precursor material 6 according to the organic film to be deposited. In some cases, the first organic precursor material 4 and the second organic precursor material 6 may be the same material (in this case, not the doping function but only the film forming function of the same material; described later) (Refer to the third to fifth embodiments).

  As described above, according to the configuration of the semiconductor manufacturing apparatus 1 of the first embodiment, the host material is vapor-deposited on the substrate W by the vacuum vapor deposition method capable of high-speed and high-precision film formation, and the concentration controllability is achieved. By depositing the guest material on the substrate W by an excellent OVPD method, a thin film in which the guest material is mixed (doping) with high precision in the host material is created, so that the doping concentration controllability of the organic film is excellent. A small amount of doping can be performed uniformly, and a high-performance organic film having a high packing density can be formed on a substrate.

Second Embodiment
FIG. 2 is a schematic view showing a second embodiment of a semiconductor manufacturing apparatus to which the thin film forming apparatus according to the present invention is applied. In the second embodiment, the configuration of the reaction apparatus 10 is different from the configuration of the first embodiment. For the vaporizer 80 side, the same configuration as in the first embodiment is used. The reactor 10 of the second embodiment is different from the first embodiment in the shape and arrangement of the OVPD gas nozzle supplied from the vaporizer 80 side and the shape and arrangement of the crucible 14.

  Specifically, first, the exhaust pipe 19 is provided on the upper part of the crucible 14. Further, an OVPD injector 187 having a substantially elongated discharge portion for the mixed steam 8 is attached to a discharge end 87a of a pipe 87 extending from the vaporizer 80 side into the film forming chamber 11. Yes. Only one OVPD injector 187 may be attached as shown in FIG. 2 (A), or a plurality (two in the figure) may be attached as shown in FIG. 2 (B). In the case of attaching a plurality, it is preferable to arrange them evenly with respect to the substrate W.

  In addition, it is good to consider the attachment position of the exhaust pipe 19, regardless of whether it is one or plural. That is, the second organic precursor material 6 contained in the mixed vapor 8 injected from the OVPD injector 187 and the first organic precursor material 4 from the crucible 14 are mixed well on the substrate W and are mixed into the substrate W. Consider being deposited. In the example shown in FIG. 2, the opening of the OVPD injector 187 is arranged to extend to the vicinity of the substrate W. In this case, in the process in which the first organic precursor material 4 emitted from the evaporation source 130 reaches the substrate W as the material gas 4a and adheres to the substrate W, it is led out from the opening of the OVPD injector 187 almost at the same time. By adhering the second organic precursor material 6 to the substrate W, the second organic precursor material 6 is mixed as an additive material into the organic layer of the host material (matrix material) made of the first organic precursor material 4. (Doping).

  Further, the evaporation source 130 including the crucible 14 in which the first organic precursor material 4 is put and the heating source 120 provided around the crucible 14 is a long line-type evaporation. The source is used. This line-type evaporation source is disposed substantially parallel to the line direction of the OVPD injector 187. A substrate W as a member to be deposited is installed above the evaporation source 130. A vapor deposition mask M for limiting the vapor deposition region is installed on the evaporation source 130 side in the vicinity of the substrate W as necessary.

  The substrate W is placed on the transport mechanism 110 having a belt, a drive motor, and the like. The transport mechanism 110 allows the deposition position of the substrate W to pass through the region where the first organic precursor material 4 evaporated in the crucible 14 and the second organic precursor material 6 injected from the OVPD injector 187 are scattered. Further, a moving function for changing the relative position between the crucible 14 and the substrate W is provided. The transport mechanism 110 forms a film of an organic material toward the deposition surface of the substrate W while moving the substrate W and the deposition mask M. Any film can be used as long as the film is formed while the line-type evaporation source and OVPD injector 187 and the substrate W to be deposited are relatively moved. The substrate W is fixed and the evaporation source 130 and the OVPD are moved by a moving device (not shown). The injector 187 may be moved.

  According to the configuration of the second embodiment, since both the guest material OVPD injector 187 (gas nozzle) and the host material evaporation source 130 have a line shape, the introduction portion of the material substance to be deposited on the substrate W is wide. Can be taken. Further, there is an advantage that the organic layer can be deposited on the substrate W having a large area by using the host vapor and the guest vapor as line vapor and sliding the substrate W. That is, it is possible to easily form a film over a large area, which is suitable as an apparatus configuration example for a large substrate. By adjusting the length in the longitudinal direction orthogonal to the moving direction of the substrate W relative to the evaporation source 130 according to the substrate size (the size in the longitudinal direction), the substrate W can have various (any) sizes. Can also respond.

  In the configuration of the second embodiment, a substrate to be deposited is mounted on a carrier (similar to the transport mechanism 110) and relatively moved with respect to a plurality of line-type evaporation sources. It can be incorporated into a so-called in-line organic EL vapor deposition system (see, for example, JP-A-2002-348659) capable of continuously forming a plurality of organic layers on the substrate W.

  When an organic EL element that displays a full-color image is configured by being incorporated into an in-line method, an organic material composed of three types of organic materials corresponding to each color component of R (red), G (green), and B (blue) When the layers are formed at different pixel positions, the manufacturing tact time can be shortened. Further, as shown in the first embodiment, since the doping concentration of the organic film can be controlled with high precision, as a result, a small amount of organic material can be uniformly doped over a large substrate region, In addition, a high-performance organic film having a high packing density can be formed on a large substrate.

  Note that the doping control for the second organic precursor material 6 can use a flow rate control mechanism for the mixed vapor 8 introduced into the film forming chamber 11 as in the first embodiment. Therefore, the doping concentration controllability of the organic film is excellent and a small amount of doping can be performed uniformly.

  On the other hand, the film thickness control for the first organic precursor material 4 is performed by measuring the vapor deposition rate of the first organic precursor material 4 evaporated from the evaporation source 130 with a predetermined film thickness monitor, as in the first embodiment. A rate control method of adjusting the temperature of the evaporation source 130 may be employed so that the deposition rate of the organic material of the film thickness monitor is constant.

  However, this rate control is a relatively simple mechanism. However, when the amount of heat applied to the heating source 120 is changed, the heat of the heating source 120 is actually transferred to the first organic precursor material 4 to the deposition rate. Since it takes a long time for the change to appear, the responsiveness when controlling the deposition rate is poor, the film thickness of the organic material is controlled stably (highly), and the deposition rate is stable at the desired level. There is some difficulty in that the element substrate cannot be inserted until the process is completed.

  In order to solve this problem, the deposition rate of the first organic precursor material 4 evaporated from the evaporation source 130 is measured by a predetermined film thickness monitor, and the deposition rate of the first organic precursor material 4 of the film thickness monitor is constant. The relative movement speed of the substrate W and the evaporation source 130 may be adjusted by controlling the transport mechanism 110 (see, for example, Japanese Patent Application No. 2003-34524 by the applicant of the present application). The film thickness of the first organic precursor material 4 deposited on the substrate W becomes thinner when the relative movement speed of the evaporation source 130 and the substrate W is increased, and conversely, the film thickness becomes thicker when the relative movement speed is decreased.

  Therefore, the film thickness of the first organic precursor material 4 deposited on the substrate W using the evaporation source 130 is measured by the film thickness monitor, and based on the measurement result, the relative relationship between the evaporation source 130 and the substrate W is measured. By controlling the moving speed, the film thickness of the first organic precursor material 4 deposited on the substrate W can be controlled to coincide with a desired value.

  FIG. 3 is a schematic perspective view showing a structural example of the evaporation source 130 and the OVPD injector 187. As shown in FIG. 3A, the crucible 14 that stores the first organic precursor material 4 to be evaporated is positioned along the substrate W and the vapor deposition mask M and by a transport mechanism 110 (see FIG. 2) (not shown). The direction perpendicular to the variable direction is the longitudinal direction of the evaporation source 130 (the crucible 14). As shown in FIG. 2, a heating source 120 for heating the crucible 14 and evaporating the first organic precursor material 4 is installed around the crucible 14. Although not shown in the figure, a radiation blocker is attached for the purpose of limiting the range in which the first organic precursor material 4 evaporated from the evaporation source 130 protrudes toward the substrate W.

  As a more preferable configuration of the evaporation source 130, as shown in FIG. 3B, a plurality of minute openings 14b are formed in the upper part of the crucible 14 facing the substrate W and the evaporation mask M, and as a whole, The crucible 14 may have a structure in which the inside is sealed except for the minute opening 14b. Further, it is preferable that a plurality of projecting portions are formed on the upper portion of the crucible 14 in the projecting state in the longitudinal direction of the crucible 14, and minute openings 14 b are formed therein (for example, Japanese Patent Application No. 2002 by the present applicant). -See 367461). The outer shape of the projecting portion only needs to project from the upper surface of the crucible 14 such as a truncated cone shape or a truncated pyramid shape. The protrusion height may be equal to or higher than the upper surface of the radiation blocking body when the radiation blocking body is provided on the upper surface of the crucible 14.

  It is preferable to form the minute opening 14b in the protruding portion so as to have a shape that gradually decreases from the inside of the crucible 14 toward the first organic precursor material 4 direction. By doing so, the first organic precursor material 4 evaporated in the crucible 14 can be smoothly scattered toward the minute opening 14b, and the distribution of the evaporated first organic precursor material 4 becomes more uniform. .

  On the other hand, an OVPD injector 187 for introducing the second organic precursor material 6 into the film forming chamber 11 and vapor-depositing it on the substrate W is shown along the substrate W and the vapor deposition mask M in the same manner as the evaporation source 130. The direction perpendicular to the variable direction of the relative position by the transport mechanism 110 (see FIG. 2) that is not performed is formed to be the longitudinal direction of the OVPD injector 187. The length in the longitudinal direction may be such that the mixed vapor 8 containing the second organic precursor material 6 released from the OVPD injector 187 can cover the substrate size (in the longitudinal direction).

  The OVPD injector 187 is attached to the discharge end 87a of the pipe 87, and has a function of spreading the mixed vapor 8 including the second organic precursor material 6 led from the vaporizer 80 through the pipe 87 into a line shape and guiding it to the substrate W. What is necessary is just to have. For example, the OVPD injector 187 is assumed to have an opening formed on the substrate W side at the tip thereof. The shape of this opening may be provided as one opening 187a formed in a line shape as shown in FIG. 3A, or as a minute opening 187b as shown in FIG. 3B. A plurality may be arranged in the line direction.

  When arranging a plurality of minute openings 187b in the line direction, for example, as shown in FIG. 3C, a plurality of air passages 189 connected to the openings 187b are formed in a metal structure 188. The opposite side of the opening 187b of the air passage 189 may be connected to the discharge end 87a. Alternatively, as shown in FIG. 3D, a metal case 190 having a hollow inside as a whole is used, an opening 187b is formed on one side of the metal case 190, and a discharge end 87a is connected to the other side. Also good.

  In the case of the structure shown in FIG. 3C, the formation (manufacturing) is more difficult than in FIG. 3D, but the mixed steam 8 guided from the pipe 87 passes smoothly through the ventilation path 189 from each opening 187b. Output toward the substrate W. Therefore, when the mixed vapor 8 is injected from the pipe 87, the second organic precursor material 6 can be smoothly scattered toward the substrate W, and the distribution of the second organic precursor material 6 becomes more uniform. Therefore, the adhesion of the second organic precursor material 6 to the substrate W can be accurately and precisely controlled, and a small amount of doping can be performed uniformly in a line shape. Even for a large substrate, there is an advantage that a high-performance film can be obtained with excellent doping concentration controllability and uniformity control of the organic film.

  On the other hand, in the case of the structure shown in FIG. 3D, the mixed steam 8 guided from the pipe 87 is output from the opening 187 b toward the substrate W while generating convection that rotates along the side wall in the metal case 190. Is done. It is difficult to control the convection. Therefore, when gas is injected from the gas introduction nozzle 26a, turbulent flow is likely to occur in the internal space, and the distribution of the second organic precursor material 6 becomes non-uniform, and FIG. ) Is inferior to vapor deposition control. However, its formation (manufacturing) is easier than that of FIG. 3C, and there is an advantage that it can be realized at low cost.

  As an example of the structure for reducing the problem of turbulent flow in the internal space in the case of the structure shown in FIG. 3D, as shown in FIG. 3E, for example, from the discharge end 87a side toward the opening 187b side. Alternatively, a metal case 190 that widens forward may be used. In this case, the side wall of the metal case 190 itself functions as an air passage that guides the mixed vapor 8 containing the second organic precursor material 6 from the discharge end 87a side toward each opening 187b. Therefore, when the mixed vapor 8 is injected from the pipe 87, the second organic precursor material 6 can be smoothly scattered toward the substrate W, and the distribution of the second organic precursor material 6 becomes more uniform. Note that such a structure of the metal case 190 is an effective technique even when one opening 187a formed in a line shape is provided on the front end side of the OVPD injector 187 as shown in FIG. .

<Structural comparison by manufacturing method>
FIG. 4 shows a structural comparison between the organic EL elements manufactured by using the film forming method according to the above embodiment and the conventional film forming method, and in particular, a device structural comparison when the light emitting region is unevenly distributed on the hole transport side of the light emitting layer. FIG. In FIG. 4, an example of the device structure is shown on the left side, and the relationship between the guest material concentration (C) and the film thickness (d) is shown in the central part. FIG. 5 is a chart showing a characteristic example of each organic EL element shown in FIG.

  Here, FIG. 4A shows an example of a device structure in which the host material uses a vacuum deposition method and the guest material uses a vacuum deposition dope. FIG. 4B shows an example of a device structure in which the host material uses the OVPD method and the guest material uses VPD dope. FIG. 4C shows an example of a device structure according to the present embodiment in which the host material is a vacuum deposition method and the guest material is OVPD dope.

  When an organic EL element is manufactured by using vacuum deposition as the host material and using vacuum deposition dope as the guest material, the response speed of controlling the doping concentration of the guest material is slow, so that only a device structure having a constant concentration in the film thickness direction can be obtained. Therefore, for example, as shown in FIG. 4A, when the light emitting region is unevenly distributed on the hole transport side of the light emitting layer, the optimum doping concentration is a function Y (thickness direction distance d from the hole transport layer / light emitting layer interface). Therefore, an excessively doped region α and an insufficiently doped region β are generated. As a result, for example, an increase in electric resistance due to concentration quenching or carrier scattering occurs in an excessively doped region, and a decrease in luminous efficiency occurs in an insufficiently doped region.

  In addition, as shown in FIG. 4B, a device in which the host material is manufactured by the LPOVP method and the guest material is manufactured by the LPOVPD method can be subjected to doping concentration modulation by carrier gas flow rate modulation, but it can transport the host material. A very large amount of carrier gas is required. For this reason, even if the carrier gas flow rate of the guest material is changed in order to modulate the doping concentration of the guest material, it takes time to mix the gas with the guest material, resulting in a time delay in the concentration modulation profile in the device. As a result, it becomes difficult to manufacture a device having a steep concentration modulation structure.

  On the other hand, by using the semiconductor manufacturing apparatus 1 of the present embodiment, an organic EL element using a host material by a vacuum vapor deposition method that is high-speed film formation, and a guest material by using an OVPD method (particularly LPOVPD method) excellent in concentration controllability. As shown in FIG. 4 (C), since only the minimum necessary carrier gas is used, the doping that the OVPD method has without causing a delay in concentration modulation time as in FIG. 4 (B). It is possible to maximize the concentration responsiveness. As a result, it is possible to form a device having an accurate doping concentration modulation having a complicated and steep doping concentration modulation with respect to the film thickness direction, so that the optimum doping concentration is obtained over the entire region of the light emitting layer. It is possible to obtain a device.

  As can be seen from these comparisons, differences in manufacturing methods cause obvious structural differences in terms of, for example, the diversity, complexity, and controllability of the doping concentration profile.

  Further, in terms of performance, as shown in FIG. 5, in terms of electro-optical performance of the device with respect to vacuum deposition, doping with a host material LPOVPD and with a guest material LPOVPD method, film defects, mechanical Clear differences occur in strength, electro-optical performance, device simplicity, and the like.

<Third Embodiment>
FIG. 6 is a schematic view showing a third embodiment of a semiconductor manufacturing apparatus to which the thin film forming apparatus according to the present invention is applied. The third embodiment is characterized in that the same material (material A) as the first organic precursor material 4 is used as the second organic precursor material 6. Thus, for example, the material A can be formed under the control of the flow rate of the OVPD gas while the material A is evaporated by a vacuum deposition method. This will be specifically described below.

  As in the first and second embodiments, the semiconductor manufacturing apparatus 1 according to the third embodiment includes the second organic material from the side of the vaporizer 80 for applying the OVPD method in the reaction apparatus 10 to which the vacuum evaporation method is applied. A mixed steam 8 containing a precursor material 6 is introduced.

  A crucible 14 as an example of an open container is provided in the lower part of the film forming chamber 11 in the figure, and a heating source 120 for evaporating the first organic precursor material 4 serving as a vapor deposition material is provided around the crucible 14. As a whole, an evaporation source (vacuum evaporation source) 130 for material A is configured.

  In addition, a substrate holding base 15 that holds a substrate W as a member to be vapor-deposited by a substrate holder (not shown) is provided on the upper portion of the crucible 14, and the degree of vapor deposition on the substrate W is provided near the substrate holding base 15. As a monitoring unit for monitoring the film thickness, a film formation rate monitor 170 for measuring the film thickness of the first and second organic precursor materials 4 and 6 (that is, the material A) deposited on the substrate W is provided.

  The substrate holding base 15 is attached to a substrate rotation mechanism 16 provided on the upper part of the film forming chamber 11 and is configured as a rotating sample holder as a whole. That is, the reaction apparatus 10 to which the rotary evaporation method can be applied by rotating the substrate W held on the substrate holding base 15 integrally with the substrate holding base 15 is configured. The substrate rotation mechanism unit 16 is also configured to serve as an exhaust pipe 19 for exhausting gas to the outside of the film forming chamber 11.

  On one side wall (lower right side in the figure) of the film forming chamber 11, a pipe 87 extending from the vaporizing device 80 side that forms the OVPD source into the film forming chamber 11 is provided. In the configuration example shown in the figure, the position of the discharge end 87 a of the pipe 87 is set near the evaporation source 130 and is introduced through the pipe 87 with the material gas 4 a of the first organic precursor material 4 emitted from the evaporation source 130. The material gas 6a (contained in the mixed vapor 8) of the second organic precursor material 6 is mixed and attached to the substrate W integrally. Thereby, the material A as each of the first and second organic precursor materials 4 and 6 is formed on the substrate W. In addition, the position of the discharge end 87a shown in the drawing is an example, and various arrangement forms can be taken as described in the first embodiment.

  A vaporizer 80 is provided on the right side of the reactor 10 in the figure. The vaporizer 80 includes a mass flow controller 90 as an OVPD gas flow rate control mechanism connected to a pipe 87 extending into the reactor 10, an internal furnace 84 that forms a raw material evaporation section, and a gas purifier 94 that forms a carrier gas source. Are arranged in series. Further, a heating mechanism 83 is provided so as to surround the mass flow controller 90, the internal furnace 84, and the gas purification device 94, and the mass flow controller 90 is connected from a pipe 87 for introducing the second organic precursor material 6 into the film forming chamber 11. All the pipes and containers up to the gas purifier 94 are temperature-controlled at a predetermined high temperature. Although not shown in the drawing, in order to realize high-accuracy gas amount control, a switching valve and a preliminary flow are provided on the path of a pipe 87 extending into the film forming chamber 11 of the reaction apparatus 10 in the same manner as in the first embodiment. Piping for is also attached.

  A crucible 85 is placed in the internal furnace 84, and the first organic precursor material 4 accommodated in the crucible 14 in the reaction apparatus 10 is stored in the crucible 85 as the second organic precursor material 6. The same material A is accommodated.

  An inert carrier gas 7 such as argon (Ar) or nitrogen (N2) in the gas purifier 94 is introduced into the pipe 89 and sent into the internal furnace 84 via a control valve and a pressure regulator (not shown). Then, it is mixed with the vapor of the second organic precursor material 6 (material A) in the internal furnace 84 and introduced into the film forming chamber 11 via the pipe 87 and the mass flow controller 90 and further via the pipe 87. Is done. As a result, the vapor 6 a of the second organic precursor material 6 flows along the pipe 87 toward the discharge end 87 a in the film forming chamber 11.

  In the above configuration, the film thickness control is not particularly performed on the vacuum evaporation source side of the first organic precursor material 4 (material A). For example, the resistance heating power of the evaporation source 130 is fixed. On the other hand, on the OVPD source side of the second organic precursor material 6 (material A), film thickness control is realized by OVPD gas flow rate control, and specifically, realized by the mass flow controller 90. This flow rate control may be self-control by the mass flow controller 90 itself, but the deposition rate monitor 170 measures the deposition rate of the material A, and passes this measurement information to the mass flow controller 90 (path indicated by a dotted line in the figure). A feedback control mechanism for controlling the flow rate of the mixed vapor 8 introduced into the film forming chamber 11 through the pipe 87 so that the vapor deposition speed of the organic material measured by the film forming speed monitor 170 is constant. This is more preferable. Note that the amount of gas introduced from the OVPD source is desirably the minimum amount necessary for film formation stability. If an excessive amount of gas is used, the degree of vacuum in the film formation chamber 11 during film formation decreases and the film density decreases. End up.

  Here, in the conventional method, the evaporation heating source is, for example, a resistance heating type, and the film formation rate is stabilized by controlling the resistance heating power so that the film formation rate monitored by the quartz vibration type film thickness meter is constant. As shown in the prior art section, stabilization is difficult.

  On the other hand, in the manufacturing method of the third embodiment, by using the same material as the first organic precursor material 4 as the second organic precursor material 6, when forming this material on the substrate W, Since the film thickness control for the second organic precursor material 6 (that is, the material A) can be performed using a flow rate control mechanism for the mixed vapor 8 introduced into the film forming chamber 11 as in the first embodiment. The film formation rate controllability can be managed with high accuracy.

  As a result, the resistance heating power of the vacuum deposition source with poor responsiveness is fixed, and the film flow rate is controlled while controlling the gas flow rate from the responsive OVPD source for correcting the film formation speed variation in vacuum deposition. Stabilization can be achieved.

  As described above, according to the semiconductor manufacturing apparatus 1 of the third embodiment, a predetermined substance is formed by forming an organic thin film in which a predetermined material is simultaneously formed by the vacuum deposition method and the OVPD method. By forming the same material on a predetermined substrate and simultaneously forming the same material while controlling the gas flow rate by the OVPD method, it has a film density equivalent to that of the vacuum evaporation method and stable film formation. Can be achieved.

  For example, when forming an electron transport layer of an organic EL device, for example, the same Alq3 is formed by OVPD while depositing Alq3 as the material A in a vacuum, thereby stably forming the electron transport layer Alq3 film. be able to. By doing so, the Alq3 film as the light emitting layer has a strict thickness, so that the effect of stabilizing the light emission efficiency can be obtained.

  The material A is not limited to the material for the electron transport layer, and can be generally applied to a non-doped layer such as a hole transport layer, a hole injection layer, a hole block layer, or an electron block layer. The mechanism of the third embodiment can also be applied to film formation of these plural layers (any combination including all layers).

  For example, if the mechanism of the third embodiment is applied to the film formation of the hole transport layer, the thickness variation of the hole transport layer is reduced, and the interference effect in the bottom emission type organic EL element is stabilized, so that the chromaticity reproduction of the emission spectrum is achieved. The effect which improves property is acquired.

  In addition, if the mechanism of the third embodiment is applied to the formation of the hole injection layer, the hole injection layer can also have a uniform thickness, and there is a merit for an element having a resonator structure as well as top / bottom emission. is there.

  In this respect, all the layers constituting the resonator between the two electrodes including the other layers such as the hole block layer and the electron block layer are required to suppress variations in film thickness. The effect of applying the form mechanism is high.

<Fourth embodiment>
FIG. 7 is a schematic view showing a fourth embodiment of a semiconductor manufacturing apparatus to which the thin film forming apparatus according to the present invention is applied. This fourth embodiment is similar to the first or second embodiment in addition to the configuration using the same material A as the first organic precursor material 4 and the second organic precursor material 6A as in the third embodiment. The OVPD method is applied to the first organic precursor material 4 (material A), and a different material B is used as another second organic precursor material 6B. Thus, the host material A can be evaporated by the vacuum deposition method, the flow rate of the host material A can be controlled by the OVPD method, and the guest material B can be doped by the OVPD method. This will be specifically described below.

  In the semiconductor manufacturing apparatus 1 of the fourth embodiment, first, similarly to the configuration of the third embodiment, the second organic reactor material 4 (host material A) is applied to the second reaction apparatus 10 to which the vacuum deposition method is applied. A mixed vapor 8A containing the second organic precursor material 6A is introduced from the vaporizer 80A side for applying the OVPD method to the organic precursor material 6A (host material A) in the vicinity of the evaporation source 130 (lower right in the figure). Side).

  In addition, the semiconductor manufacturing apparatus 1 of the fourth embodiment includes the second organic precursor material 6B from the vaporizer 80B side for applying the OVPD method to another second organic precursor material 6B (guest B). The mixed vapor 8B is configured to be introduced from the vicinity of the substrate W (upper right side in the figure).

  The configuration itself of the vaporizers 80A and 80B is the same as that of the vaporizer 80 of the third embodiment except that the mechanism of flow rate control is different. For example, as in the third embodiment, by fixing the resistance heating power of the evaporation source 130, the film thickness control on the vacuum evaporation source side for the first organic precursor material 4 (host material A) is not particularly performed. . The film thickness control on the OVPD source side for the second organic precursor material 6 (host material A) is performed via the pipe 87A so that the deposition rate of the host material A monitored by the film formation rate monitor 170 is constant. A feedback control mechanism that controls the flow rate of the mixed vapor 8A (inert carrier gas 7A + material gas 6Aa) introduced into the film forming chamber 11 by the mass flow controller 90A is used.

  On the other hand, doping control on the OVPD source side for the second organic precursor material 6 (guest material B) is introduced into the film forming chamber 11 via the pipe 87B by the mass flow controller 90A, as in the first embodiment. A flow rate control mechanism for the mixed vapor 8B (inert carrier gas 7B + material gas 6Ba) can be used. Therefore, the doping concentration controllability of the organic film is excellent and a small amount of doping can be performed uniformly.

  For example, when a predetermined material is doped into the electron transport layer of the organic EL device to form a green light emitting layer, for example, Alq3 as material A is vacuum-deposited, and the same Alq3 is formed by OVPD, while C6 By doping (coumarin 6) by the OVPD method, an electron transport layer Alq3 film in which C6 is doped in a small amount (for example, about 1%) to Alq3 can be stably formed.

  Thus, according to the semiconductor manufacturing apparatus 1 of the fourth embodiment, in addition to the same effect as the configuration of the third embodiment, the effect of the configuration of the first embodiment can be enjoyed. That is, by forming an organic thin film by performing a small amount doping of another substance by the OVPD method while simultaneously forming a predetermined substance by the vacuum evaporation method and the OVPD method, the film density is equivalent to that of the vacuum evaporation method. It is possible to stabilize the film formation, to uniformly perform a small amount of doping excellent in doping concentration controllability, and to form a high-performance organic film with high packing density.

<Fifth Embodiment>
FIG. 8 is a schematic view showing a fifth embodiment of a semiconductor manufacturing apparatus to which the thin film forming apparatus according to the present invention is applied. The fifth embodiment is characterized in that the vacuum deposition method is applied to the material B in addition to the configuration of the fourth embodiment. Thereby, the host material A is evaporated by the vacuum deposition method, the flow rate of the host material A is controlled by the OVPD method, and the doping of the guest material B is further performed by the vacuum deposition method and the OVPD method. It can be. This will be specifically described below.

  In the semiconductor manufacturing apparatus 1 of the fifth embodiment, first, in the film forming chamber 11 of the reaction apparatus 10, in addition to the evaporation source 130A forming the vacuum evaporation source A for the host material A, the vacuum evaporation source for the guest material B An evaporation source 130B forming A is provided. The evaporation source 130B is disposed on the opposite side (left side in the drawing) of the pipe 87 introduced from the vaporizer 80A for the host material A across the evaporation source 130A. The evaporation sources 130A and 130B differ only in the materials accommodated in the crucibles 14A and 14B, and the configuration itself is the same as that of the evaporation source 130 of the fourth embodiment.

  In addition to the deposition rate monitor 170 A for the host material A, a deposition rate monitor 170 B for the guest material is provided in the deposition chamber 11. Each arrangement position and direction are considered so that the other substance does not adhere to each. Specifically, the film formation speed monitor 170A is arranged in the same position and orientation as the film formation speed monitor 170 in the third and fourth embodiments. On the other hand, the film formation rate monitor 170B is disposed in the vicinity of the evaporation source 130B and away from the evaporation source 130A, and generally can monitor only the film formation rate of the guest material B from the crucible 14B. Yes.

  Further, a shielding plate 128 is disposed between the film formation rate monitor 170B and the film formation rate monitor 170A so that the vaporized gas of the guest material B from the crucible 14B does not reach the film formation rate monitor 170A. Thus, the film formation rate monitor 170A can monitor only the film formation rate of the host material A from the crucible 14A.

  Note that, as in the first embodiment, the guest material B as the second organic precursor material 6 introduced from the vaporizer 80B side also adheres to the deposition rate monitor 170A, so this second organic precursor material 6 is measured, but the influence of the guest material B can be ignored when a small amount of doping is performed from the vaporizer 80B side.

  In the semiconductor manufacturing apparatus 1 having such a configuration, the evaporation source 130A for the first first organic precursor material 4 (host material A) and the first second organic precursor material 6 (guest material B) are used. For the evaporation source 130B, as in the case of the host material A of the fourth embodiment, the film thickness control is not particularly performed with the resistance heating power of the vacuum evaporation source fixed.

  On the other hand, the film thickness control on the OVPD source side for the second first organic precursor material 4 (host material A) is performed so that the deposition rate of the host material A monitored by the film formation rate monitor 170A is constant. The mass flow controller 90A controls the flow rate of the mixed vapor 8A (inert carrier gas 7A + material gas 6Aa) introduced into the film forming chamber 11 through 87A.

  The doping control on the OVPD source side for the second second organic precursor material 6 (guest material B) is monitored by the film formation rate monitor 170B for correcting the doping amount variation of the guest material B in vacuum deposition. The mass flow controller 90B controls the flow rate of the mixed vapor 8B (inert carrier gas 7B + material gas 6Ba) introduced into the film forming chamber 11 through the pipe 87B so as to correct the doping rate of the guest material B to be corrected. And

  By doing so, a configuration suitable for high-concentration dope can be obtained. That is, in the configuration of the fourth embodiment, when the second organic precursor material 6 (guest material B) is doped at a high concentration from the OVPD source side, the flow rate of the OVPD gas becomes large, and the gas 6a of the guest material B is insignificant. A large amount of the mixed vapor 8B containing the active carrier gas 7 is introduced into the film forming chamber 11, and the degree of vacuum in the film forming chamber 11 during film formation is lowered. For example, a gas existing in a low vacuum is caught in the film. This may cause a problem that the film becomes rough (the film density decreases).

  On the other hand, in the configuration of the fifth embodiment, the guest material B is also doped by the vacuum vapor deposition method and the OVPD method, so that the basic part of the high concentration doping is performed by the vacuum vapor deposition method, while the OVPD source side By using the flow rate control mechanism for the mixed steam 8B, fine adjustment of the doping amount can be realized. That is, the doping can be stabilized by controlling the gas flow rate from the OVPD source with good responsiveness for correcting the doping rate variation in the vacuum deposition method. Therefore, an increase in the OVPD gas flow rate can be avoided, the doping concentration controllability is excellent, and high concentration doping can be performed uniformly.

  For example, when a light emitting layer is formed by doping a predetermined material into the electron transport layer of an organic EL device, it is necessary to mix (dope) the guest material B in a large amount with respect to the host material A depending on the light emission color or the doping material. In some cases, the amount of the guest material B may be larger than that of the host material A as a result. In such a case, for example, Alq3 as the host material A is vacuum-deposited while forming the same Alq3 by the OVPD method, and in addition, the same dope B is doped by the OVPD method while the predetermined doping material B is vacuum-deposited. Thus, the electron transport layer Alq3 film in which the doping material B is doped at a high concentration in Alq3 can be stably formed.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various changes or improvements can be added to the above-described embodiment without departing from the gist of the invention, and embodiments to which such changes or improvements are added are also included in the technical scope of the present invention.

  Further, the above embodiments do not limit the invention according to the claims (claims), and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. Absent. The embodiments described above include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. Even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, as long as an effect is obtained, a configuration from which these some constituent requirements are deleted can be extracted as an invention.

  For example, the above-described embodiment can be applied to multi-doping in which a plurality of doping materials are introduced into a deposition chamber to which a vacuum deposition method is applied. In this case, the OVPD method is applied to each doping material mixed in the same host material layer as described above. Also in this multi-doping, any structure of the first embodiment and the second embodiment can be adopted. The shape of each injector part is also set accordingly.

  Moreover, in the said embodiment, although demonstrated in the example applied to doping of the guest material to the host material at the time of manufacturing an organic EL element, the application range is not necessarily restricted to such a thing, It is on a semiconductor substrate. The present invention can also be applied to other film forming techniques for manufacturing a thin film. For example, attaching a combination or mixture of multiple precursors to a substrate, attaching a chemical reaction of multiple precursors to a substrate, attaching a precursor material to a substrate as a donor / acceptor, etc. It can also be applied to.

It is the schematic which shows 1st Embodiment of the semiconductor manufacturing apparatus to which the thin film forming apparatus which concerns on this invention is applied. It is the schematic which shows 1st Embodiment of the semiconductor manufacturing apparatus to which the thin film forming apparatus which concerns on this invention is applied. It is a typical perspective view which shows the structural example of an evaporation source and an OVPD injector. It is a figure which shows the structure comparison of the organic EL element manufactured using the film-forming method by this embodiment, and the conventional film-forming method. 5 is a chart showing an example of characteristics of each organic EL element shown in FIG. 4. It is the schematic which shows 3rd Embodiment of the semiconductor manufacturing apparatus to which the thin film forming apparatus which concerns on this invention is applied. It is the schematic which shows 4th Embodiment of the semiconductor manufacturing apparatus to which the thin film forming apparatus which concerns on this invention is applied. It is the schematic which shows 5th Embodiment of the semiconductor manufacturing apparatus to which the thin film forming apparatus which concerns on this invention is applied. It is a figure which shows the structural example of the semiconductor manufacturing apparatus to which the vacuum evaporation method is applied. It is a figure which shows the structural example of the semiconductor manufacturing apparatus to which the LPOVPD method is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Semiconductor manufacturing apparatus, 4 ... 1st organic precursor material, 6 ... 2nd organic precursor material, 7 ... Inert carrier gas, 8 ... Mixed steam, 10 ... Reactor, 11 ... Film-forming chamber, 14 ... Crucible DESCRIPTION OF SYMBOLS 14, 14a ... Opening part, 14b ... Micro opening, 15 ... Substrate holding base, 16 ... Substrate rotation mechanism part, 17 ... Quartz-type film thickness meter, 19 ... Exhaust pipe, 80, 80A, 80B ... Vaporizer ... heating furnace, 83 ... heating mechanism, 84 ... internal furnace, 85 ... crucible, 86 ... switching valve, 87, 87A, 87B, 88, 89 ... piping, 90, 90A, 90B ... mass flow controller, 92 ... pressure regulator 94 ... Gas purification device, 96 ... Control valve, 110 ... Conveyance mechanism, 120 ... Heat source, 128 ... Shield plate, 130, 130A, 130B ... Evaporation source, Evaporation source 170, 170A, 170B ... Deposition rate monitor, 1 7 ... OVPD injector, M ... deposition mask, W ... board

Claims (30)

A thin film forming method for forming a thin film on the substrate by attaching the evaporated material to the substrate,
Supplying a first precursor material to the substrate by vacuum evaporation; and
A method for forming a thin film, comprising supplying a second precursor material to the substrate by a vapor phase method. The thin film forming method according to claim 1, wherein the same material is used as each of the first and second precursor materials. While using the same material as the first precursor material as one of the second precursor materials,
The thin film forming method according to claim 1, wherein a substance different from the first precursor material is used as the other of the second precursor materials. While using the first substance as the first and second precursor materials,
2. The thin film forming method according to claim 1, wherein a material different from the first material is used as each of the first and second precursor materials. The first precursor material is a host material formed on the substrate;
The thin film forming method according to claim 1, wherein the second precursor material is a guest material mixed with the host material. The thin film forming method according to claim 1, wherein the first precursor material is an organic precursor. The thin film forming method according to claim 1, wherein the second precursor material is introduced into a film forming furnace to which the vacuum deposition method is applied using an inert gas. The thin film forming method according to claim 7, wherein the inert gas is selected from the group consisting of nitrogen, argon, hydrogen, helium, neon, krypton, and xenon. The thin film forming method according to claim 1, wherein a flow rate of the second precursor material introduced into the film forming furnace is controlled. The thin film forming method according to claim 9, wherein the flow rate is controlled while monitoring a degree of deposition of the precursor material on the substrate. A thin film forming apparatus for forming a thin film on the substrate by attaching the evaporated material to the substrate,
A film forming furnace for supplying the first precursor material to the substrate by a vacuum deposition method;
A vaporizer for vaporizing the second precursor material;
A thin film forming apparatus comprising: a pipe for introducing the second precursor material vaporized by the vaporizer into the film forming furnace. The vaporizer includes an opening container that has an opening and accommodates the second precursor material;
A heating mechanism substantially surrounding the open container;
The thin film forming apparatus according to claim 11, comprising: An inert gas supply unit for supplying an inert gas for transporting the second precursor material to the vaporizer;
The second precursor material vaporized by the vaporizer is mixed with the inert gas supplied from the inert gas supply unit, and the mixed vapor is mixed via the pipe. It introduce | transduces in a film furnace. The thin film formation apparatus of Claim 11 characterized by the above-mentioned. The inert gas supply unit supplies at least one gas of the group consisting of nitrogen, argon, hydrogen, helium, neon, krypton, and xenon to the vaporizer as the inert gas. The thin film forming apparatus according to claim 11. The thin film forming apparatus according to claim 11, further comprising a flow rate control unit configured to control a flow rate of the second precursor material introduced into the film forming furnace. The flow rate control unit includes a mass flow controller provided in a part of a pipe for supplying the inert gas from the inert gas supply unit to the vaporizer. The thin film forming apparatus according to claim 15, wherein the apparatus is a thin film forming apparatus. A monitoring unit for monitoring the degree of deposition of the precursor material on the substrate;
The thin film forming apparatus according to claim 15, wherein the flow rate control unit controls the flow rate with reference to a monitoring result from the monitoring unit. The film forming furnace
An open container having an opening and containing the first precursor material;
A heating mechanism substantially surrounding the open container;
A holding mechanism that holds the substrate at a position substantially opposite to the opening of the opening container;
The thin film forming apparatus according to claim 11, further comprising: an exhaust pipe connected to a vacuum pump provided outside. 19. The thin film forming apparatus according to claim 18, wherein, in the film forming furnace, a tip end of the pipe is disposed substantially on a side opposite to the exhaust pipe with the open container interposed therebetween. The thin film forming apparatus according to claim 19, wherein a tip end of the pipe extends to the vicinity of the open container. 19. The thin film forming apparatus according to claim 18, wherein a tip end of the pipe extends to a vicinity of the substrate held by the holding mechanism in the film forming furnace. The evaporation source having the opening container and the heating mechanism in the film forming furnace is formed in a long shape,
A gas containing the second precursor material is elongated at the tip of a pipe for introducing the second precursor material vaporized by the vaporizer into the film forming furnace, and the vapor deposition source Is provided with a lead-out end that leads substantially parallel to the longitudinal direction of
further,
A moving mechanism that relatively moves the evaporation source and the lead-out end and the substrate in a direction orthogonal to the longitudinal direction of the evaporation source;
A film thickness measuring unit for measuring the film thickness of the precursor material adhered to the substrate;
The thin film forming apparatus according to claim 11, further comprising: a moving speed control unit that controls a relative moving speed of the moving mechanism unit based on a measurement result of the film thickness measuring unit. The leading end is
A plurality of openings are formed at the tip along the longitudinal direction,
23. The thin film forming apparatus according to claim 22, wherein an air passage that guides a gas containing the second precursor material from the pipe side toward the plurality of openings is formed. The thin film forming apparatus according to claim 17, comprising a plurality of the vaporizers and the pipes. One of the vaporizers vaporizes the same material as the first precursor material as one of the second precursor materials,
One of the pipes introduces the one second precursor material vaporized by the one vaporizer into the film forming furnace,
The other of the vaporizers vaporizes a substance different from the first precursor material as the other of the second precursor materials,
25. The thin film forming apparatus according to claim 24, wherein the other of the pipes introduces the other second precursor material vaporized by the other vaporizer into the film forming furnace. 25. The thin film according to claim 24, wherein the film forming furnace includes an opening and a plurality of opening containers that contain the first precursor material and a heating mechanism that substantially surrounds the opening container. Forming equipment. Each of the heating mechanism sections vaporizes different substances as the first precursor material,
One of the vaporizers vaporizes the same material as one of the first precursor materials as one of the second precursor materials,
One of the pipes introduces the one second precursor material vaporized by the one vaporizer into the film forming furnace,
The other of the vaporizers vaporizes the same substance as the other of the first precursor material as the other of the second precursor material,
27. The thin film forming apparatus according to claim 26, wherein the other of the pipes introduces the other second precursor material vaporized by the other vaporizer into the film forming furnace. The first precursor material is a host material formed on the substrate;
The thin film forming apparatus according to claim 11, wherein the second precursor material is a guest material mixed with the host material. The thin film forming apparatus according to claim 11, wherein the first precursor material is an organic precursor. A semiconductor device in which a thin film is formed on a substrate,
A first precursor material is supplied to the substrate by a vacuum deposition method, and a second precursor material is supplied to the substrate by a vapor phase method, whereby the first precursor material is included in the first precursor material. 2 precursor materials are doped,
A semiconductor device having a structure with an accurate doping concentration modulation in the film thickness direction.

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