JP2011151081A - Substrate processing apparatus - Google Patents

Abstract

A substrate processing apparatus capable of preventing the influence of high-frequency noise is provided.
An insulating wiring covering member 210 in which a noise removing filter 212 for removing high frequency noise is connected to a heater power supply line 208 that supplies power to a heater 207 and a conductive wiring 209 of the heater power supply line 208 is covered. , A shield member 211 that shields high-frequency noise is incorporated between the heater 207 and the noise removal filter 212. A noise removing filter 262 that removes high-frequency noise is connected to the compensation lead 264 of the thermocouple 263, and a shield that shields high-frequency noise is provided inside the insulating wiring covering member 266 that covers the conductive wiring 265 of the compensation lead 264. A member 268 is incorporated between the thermocouple 263 and the noise removal filter 262.
[Selection] Figure 4

Description

  The present invention relates to a substrate processing apparatus, for example, in a method of manufacturing a semiconductor integrated circuit device (hereinafter referred to as an IC) including a semiconductor element, and is used to perform plasma processing on a semiconductor wafer (hereinafter referred to as a wafer) in which an IC is formed. And what is effective.

In an IC manufacturing method, as a substrate processing apparatus for performing plasma processing on a wafer, a process tube forming a processing chamber into which a plurality of wafers are carried, a gas supply pipe for supplying gas into the processing chamber, and a wafer in the processing chamber A pair of elongated electrodes disposed close to each other at a position away from the group carrying-in region, and a power source that applies high-frequency power between the pair of electrodes, and a processing gas is supplied to the space between the pair of electrodes A batch-type plasma processing apparatus configured as described above has been proposed (see, for example, Patent Document 1).
In this batch type plasma processing apparatus, plasma can be generated over the entire length of the pair of electrodes, so that the plasma processing can be performed uniformly over the entire length of the wafer group.

JP 2004-289166 A

In a batch type plasma processing apparatus, high frequency noise generated by plasma generation may cause malfunction of electrical equipment. High-frequency noise leaks to the surroundings as electromagnetic waves, or leaks through sheet metal or conductors. When plasma is generated in the processing chamber heated by the heater, high-frequency noise may leak through the heater wire and the control temperature sensor wiring.
The following can be considered as measures against high frequency noise.
(1) High frequency noise is shielded by sheet metal or wire mesh.
(2) Use shielded wires so that signal lines of electrical equipment are not affected by high-frequency noise. (3) Wrap a shield material around the cable.
(4) Drop the shield to ground.
(5) A noise filter is provided in the circuit to remove high frequency noise.

However, when shielded by sheet metal or the like, high-frequency noise leaks from the gaps (slits) between the panels, and thus high sealing performance is required. As a result, it becomes necessary to use a large amount of screws and fix them without gaps, or to use conductive packing.
Also in the measures to cover or wrap with the shielding material, a gap is generated at the end portion or becomes bulky.
High-frequency noise transmitted through the wiring can be removed by the noise filter, but for the heater wire and control temperature sensor wiring, the noise filter cannot be installed adjacent to the heater from the viewpoint of heat resistance. That is, leakage of high frequency noise from a portion between the heater and the noise filter cannot be prevented.

  An object of the present invention is to provide a substrate processing apparatus capable of preventing the influence of high frequency noise.

According to one aspect of the present invention, the following substrate processing apparatus is provided.
A processing chamber for processing the substrate;
A gas supply system for supplying gas into the processing chamber;
A plasma source for activating the gas supplied from the gas supply system with plasma;
A heater for heating the substrate in the processing chamber;
A temperature sensor for measuring the temperature in the processing chamber;
A heater power line connected to the heater;
A temperature sensor compensating lead wire connected to the temperature sensor;
The heater power line and the temperature sensor compensation conductor have a configuration in which conductive wiring is covered with an insulating wiring covering member, and the heater power line and / or the temperature sensor compensation conductor A substrate processing apparatus, wherein a shield member that shields high-frequency noise generated by the plasma is incorporated in the wiring covering member.

  According to this substrate processing apparatus, it is possible to prevent the influence of high frequency noise.

It is a schematic block diagram of the vertical processing furnace of the substrate processing apparatus used suitably by this embodiment, and is a figure which shows a processing furnace part with a vertical cross section. It is a schematic block diagram of the vertical processing furnace of the substrate processing apparatus used suitably by this embodiment, and is a figure which shows a processing furnace part with the sectional view on the AA line of FIG. It is a figure which shows the timing of the gas supply and plasma power supply in the process sequence of this embodiment. It is a schematic diagram which shows the electric circuit of the heater and temperature sensor of this embodiment. (A) And (b) is the perspective view and longitudinal cross-sectional view which show the power supply line for heaters, (c) is a longitudinal cross-sectional view which shows a compensation conducting wire.

  Embodiments of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the processing furnace 202 includes a heater 207 as a heating means (heating mechanism). The heater 207 has a cylindrical shape and is vertically installed by being supported by a heater base (not shown) as a holding plate. The heater 207 also functions as an activation mechanism that activates gas with heat, as will be described later.

Inside the heater 207, a reaction tube 203 constituting a reaction vessel (processing vessel) concentrically with the heater 207 is disposed. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO ₂ ) or silicon carbide (SiC), and has a cylindrical shape with the upper end closed and the lower end opened. A processing chamber 201 is formed in a hollow cylindrical portion of the reaction tube 203, and is configured to be able to accommodate wafers 200 as substrates in a state of being aligned in multiple stages in a horizontal posture and in a vertical direction by a boat 217 described later.

  A first nozzle 249 a and a second nozzle 249 d are provided below the reaction tube 203 in the processing chamber 201 so as to penetrate the reaction tube 203. A first gas supply pipe 232a and a second gas supply pipe 232d are connected to the first nozzle 249a and the second nozzle 249d, respectively. As described above, the reaction tube 203 is provided with the two nozzles 249a and 249d and the two gas supply tubes 232a and 232d, and supplies a plurality of types of gases into the processing chamber 201, here two types of gases. It is configured to be able to.

  The first gas supply pipe 232a is provided with a mass flow controller (MFC) 241a that is a flow rate controller (flow rate control unit) and a valve 243a that is an on-off valve in order from the upstream direction. A first inert gas supply pipe 232e is connected to the downstream side of the valve 243a of the first gas supply pipe 232a. The first inert gas supply pipe 232e is provided with a mass flow controller 241e that is a flow rate controller (flow rate control unit) and a valve 243e that is an on-off valve in order from the upstream direction. The first nozzle 249a described above is connected to the tip of the first gas supply pipe 232a. The first nozzle 249a is provided in an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200 so as to rise upward from the lower portion of the inner wall of the reaction tube 203 in the stacking direction of the wafer 200. It has been. The first nozzle 249a is configured as an L-shaped long nozzle. A gas supply hole 250a for supplying gas is provided on the side surface of the first nozzle 249a. The gas supply hole 250 a is opened to face the center of the reaction tube 203. A plurality of gas supply holes 250a are provided from the bottom to the top of the reaction tube 203, each having the same opening area, and further provided at the same opening pitch. A first gas supply system is mainly configured by the first gas supply pipe 232a, the mass flow controller 241a, the valve 243a, and the first nozzle 249a. Further, a first inert gas supply system is mainly configured by the first inert gas supply pipe 232e, the mass flow controller 241e, and the valve 243e.

  The second gas supply pipe 232d is provided with a mass flow controller (MFC) 241d that is a flow rate controller (flow rate control unit) and a valve 243d that is an on-off valve in order from the upstream direction. A second inert gas supply pipe 232h is connected to the downstream side of the valve 243d of the second gas supply pipe 232d. The second inert gas supply pipe 232h is provided with a mass flow controller 241h that is a flow rate controller (flow rate control unit) and a valve 243h that is an on-off valve in order from the upstream direction. The second nozzle 249d is connected to the tip of the second gas supply pipe 232d. The second nozzle 249d is provided in a buffer chamber 237 that is a gas dispersion space.

  The buffer chamber 237 is provided in a circular arc space between the inner wall of the reaction tube 203 and the wafer 200 in a portion extending from the lower part to the upper part of the inner wall of the reaction tube 203 along the loading direction of the wafer 200. A gas supply hole 250e for supplying gas is provided at the end of the wall of the buffer chamber 237 adjacent to the wafer 200. The gas supply hole 250e is opened to face the center of the reaction tube 203. A plurality of the gas supply holes 250e are provided from the lower part to the upper part of the reaction tube 203, each having the same opening area, and further provided at the same opening pitch.

  The second nozzle 249d is located at the end of the buffer chamber 237 opposite to the end where the gas supply hole 250e is provided, and extends upward from the lower portion of the inner wall of the reaction tube 203 in the stacking direction of the wafer 200. It is provided to stand up. The second nozzle 249d is configured as an L-shaped long nozzle. A gas supply hole 250d for supplying a gas is provided on a side surface of the second nozzle 249d. The gas supply hole 250d is opened to face the center of the buffer chamber 237. A plurality of gas supply holes 250 d are provided from the lower part to the upper part of the reaction tube 203, similarly to the gas supply holes 250 e of the buffer chamber 237. Each of the gas supply holes 250d has the same opening area from the upstream side (lower part) to the downstream side (upper part) when the differential pressure between the buffer chamber 237 and the processing chamber 201 is small. However, when the differential pressure is large, the opening area is increased or the opening pitch is decreased from the upstream side toward the downstream side.

  In the present embodiment, by adjusting the opening area and opening pitch of the gas supply holes 250d of the second nozzle 249d from the upstream side to the downstream side as described above, first, from each of the gas supply holes 250d, Although there is a difference in flow velocity, gas with the same flow rate is ejected. Then, the gas ejected from each of the gas supply holes 250d is once introduced into the buffer chamber 237, and the flow velocity difference of the gas is made uniform in the buffer chamber 237.

  That is, the gas ejected into the buffer chamber 237 from each of the gas supply holes 250d of the second nozzle 249d has its particle velocity reduced in the buffer chamber 237, and then the processing chamber from the gas supply holes 250e of the buffer chamber 237. It spouts into 201. Accordingly, when the gas ejected into the buffer chamber 237 from each of the gas supply holes 250d of the second nozzle 249d is ejected into the processing chamber 201 from each of the gas supply holes 250e of the buffer chamber 237, a uniform flow rate is obtained. And a gas having a flow rate.

  A second gas supply system is mainly configured by the second gas supply pipe 232d, the mass flow controller 241d, the valve 243d, the second nozzle 249d, and the buffer chamber 237. Further, a second inert gas supply system is mainly configured by the second inert gas supply pipe 232h, the mass flow controller 241h, and the valve 243h.

From the first gas supply pipe 232a, for example, a silicon source gas, that is, a gas containing silicon (Si) (silicon-containing gas) is supplied into the processing chamber 201 through the mass flow controller 241a, the valve 243a, and the first nozzle 249a. Is done. As the silicon-containing gas, for example, dichlorosilane (SiH ₂ Cl ₂ , abbreviation: DCS) gas can be used.

From the second gas supply pipe 232d, for example, a gas (nitrogen-containing gas) containing nitrogen (N) is supplied into the processing chamber 201 through the mass flow controller 241d, the valve 243d, the second nozzle 249d, and the buffer chamber 237. . As the nitrogen-containing gas, for example, ammonia (NH ₃ ) gas can be used.

For example, nitrogen (N ₂ ) gas is supplied from the inert gas supply pipes 232e and 232h through mass flow controllers 241e and 241h, valves 243e and 243h, gas supply pipes 232a and 232d, gas nozzles 249a and 249d, and a buffer chamber 237, respectively. It is supplied into the processing chamber 201.

  Note that, for example, when the above-described gases are supplied from the respective gas supply pipes, the first gas supply system constitutes a source gas supply system, that is, a silicon-containing gas supply system (silane-based gas supply system). Further, a nitrogen-containing gas supply system is configured by the second gas supply system.

  In the buffer chamber 237, as shown in FIG. 2, a first rod-shaped electrode 269 that is a first electrode having an elongated structure and a second rod-shaped electrode 270 that is a second electrode are provided at the bottom of the reaction tube 203. The upper part is disposed along the stacking direction of the wafers 200. Each of the first rod-shaped electrode 269 and the second rod-shaped electrode 270 is provided in parallel with the second nozzle 249d. Each of the first rod-shaped electrode 269 and the second rod-shaped electrode 270 is protected by being covered with an electrode protection tube 275 that is a protection tube that protects each electrode from the top to the bottom. Either the first rod-shaped electrode 269 or the second rod-shaped electrode 270 is connected to the high-frequency power source 273 via the matching unit 272, and the other is connected to the ground as the reference potential. As a result, plasma is generated in the plasma generation region 224 between the first rod-shaped electrode 269 and the second rod-shaped electrode 270. The first rod-shaped electrode 269, the second rod-shaped electrode 270, the electrode protection tube 275, the matching unit 272, and the high-frequency power source 273 mainly constitute a plasma source as a plasma generator (plasma generating unit). The plasma source functions as an activation mechanism that activates a gas with plasma as will be described later.

  The electrode protection tube 275 has a structure in which each of the first rod-shaped electrode 269 and the second rod-shaped electrode 270 can be inserted into the buffer chamber 237 while being isolated from the atmosphere of the buffer chamber 237. Here, if the inside of the electrode protection tube 275 has the same atmosphere as the outside air (atmosphere), the first rod-shaped electrode 269 and the second rod-shaped electrode 270 inserted into the electrode protection tube 275 are oxidized by heat from the heater 207. It will be. Therefore, the inside of the electrode protection tube 275 is filled or purged with an inert gas such as nitrogen to suppress the oxygen concentration sufficiently low to prevent oxidation of the first rod-shaped electrode 269 or the second rod-shaped electrode 270. An active gas purge mechanism is provided.

  The reaction tube 203 is provided with an exhaust pipe 231 for exhausting the atmosphere in the processing chamber 201. The exhaust pipe 231 is evacuated via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). A vacuum pump 246 serving as an exhaust device is connected, and the processing chamber 201 can be evacuated so that the pressure in the processing chamber 201 becomes a predetermined pressure (degree of vacuum). Note that the APC valve 244 is an open / close valve that can open and close the valve to evacuate / stop the evacuation in the processing chamber 201 and further adjust the valve opening to adjust the pressure. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 244, the vacuum pump 246, and the pressure sensor 245.

  Below the reaction tube 203, a seal cap 219 is provided as a furnace opening lid capable of airtightly closing the lower end opening of the reaction tube 203. The seal cap 219 is brought into contact with the lower end of the reaction tube 203 from the lower side in the vertical direction. The seal cap 219 is made of a metal such as stainless steel and has a disk shape. An O-ring 220 is provided on the upper surface of the seal cap 219 as a seal member that contacts the lower end of the reaction tube 203. A rotation mechanism 267 for rotating the boat is installed on the side of the seal cap 219 opposite to the processing chamber 201. A rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and is connected to a boat 217 described later, and is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be lifted vertically by a boat elevator 115 as a lifting mechanism vertically installed outside the reaction tube 203, and thereby the boat 217 is carried into and out of the processing chamber 201. It is possible.

  The boat 217 as a substrate support is made of a heat-resistant material such as quartz or silicon carbide, and is configured to support a plurality of wafers 200 in a horizontal posture and aligned in a state where the centers are aligned with each other in multiple stages. ing. A heat insulating member 218 made of a heat resistant material such as quartz or silicon carbide is provided at the lower part of the boat 217 so that heat from the heater 207 is not easily transmitted to the seal cap 219 side. The heat insulating member 218 may be constituted by a plurality of heat insulating plates made of a heat resistant material such as quartz or silicon carbide, and a heat insulating plate holder that supports them in a horizontal posture in multiple stages.

  A temperature sensor 263 as a temperature detector is installed in the reaction tube 203, and the temperature in the processing chamber 201 is adjusted by adjusting the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263. It is configured to have a desired temperature distribution. The temperature sensor 263 is configured in an L shape similarly to the nozzles 249a and 249d, and is provided along the inner wall of the reaction tube 203.

  The controller 121 which is a control unit (control means) includes mass flow controllers 241a, 241d, 241e, 241h, valves 243a, 243d, 243e, 243h, pressure sensor 245, APC valve 244, vacuum pump 246, heater 207, temperature sensor 263, The boat rotation mechanism 267, the boat elevator 115, the high frequency power supply 273, the matching unit 272, and the like are connected. The controller 121 controls the flow rate of various gases by the mass flow controllers 241a, 241d, 241e, 241h, the opening / closing operation of the valves 243a, 243d, 243e, 243h, the opening / closing of the APC valve 244, and the pressure adjusting operation based on the pressure sensor 245, the temperature sensor. Control of heater 207 temperature adjustment operation based on H.263, start / stop of vacuum pump 246, rotation speed adjustment operation of boat rotation mechanism 267, raising / lowering operation of boat elevator 115, power supply control of high frequency power supply 273, matching unit 272 Impedance control is performed.

Next, an example of a processing sequence for forming an insulating film on a substrate will be described as one step of a semiconductor device (device) manufacturing process using the processing furnace of the substrate processing apparatus described above.
In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

  FIG. 3 is a timing diagram of gas supply and plasma power supply in the processing sequence of the present embodiment.

In the processing sequence of the present embodiment, the first layer containing the first element is formed on the wafer 200 by supplying the gas containing the first element (first element-containing gas) into the processing container containing the wafer 200. Forming, and
Supplying a gas containing a second element (second element-containing gas) into the processing container to modify the first layer to form a second layer containing the first element and the second element; ,
Is performed at least once, thereby forming a thin film containing the first element and the second element having a predetermined film thickness.

  The step of forming the first layer is performed under conditions that cause a CVD reaction. At this time, the first element layer is formed on the wafer 200 as a first layer containing the first element of less than one atomic layer to several atomic layers. The first layer may be an adsorption layer for the first element-containing gas. As the first element, it is preferable to use an element that becomes a solid alone. Here, the first element layer is a generic name including a continuous layer composed of the first element, a discontinuous layer, and a thin film formed by overlapping these layers. The continuous layer composed of the first element may be referred to as a thin film. The first element-containing gas adsorption layer includes a discontinuous chemical adsorption layer as well as a continuous chemical adsorption layer of gas molecules of the first element-containing gas. In addition, the layer less than 1 atomic layer means the atomic layer formed discontinuously. Under conditions where the first element-containing gas is self-decomposing, the first element is deposited on the wafer 200 to form a first element layer. Under conditions where the first element-containing gas does not self-decompose, the first element-containing gas is adsorbed on the wafer 200 to form an adsorption layer of the first element-containing gas. In addition, it is preferable to form the first element layer on the wafer 200 because the deposition rate can be increased, rather than forming the adsorption layer of the first element-containing gas on the wafer 200.

  In the step of forming the second layer, the second element-containing gas is activated by plasma or heat to be supplied, thereby causing a part of the first layer to react with the second element-containing gas. This layer is modified to form a second layer containing the first element and the second element. For example, when the first layer containing the first element of several atomic layers is formed in the step of forming the first layer, a part of the surface layer may react with the second element-containing gas, The entire surface layer may react with the second element-containing gas. Alternatively, the second element-containing gas may react with several layers below the surface layer of the first layer containing the first element including several atomic layers. As the second element, it is preferable to use an element that does not become a solid by itself. The second element-containing gas may be supplied after being activated by plasma, or may be supplied after being activated by heat. FIG. 3 shows an example in which the second element-containing gas is activated by plasma and supplied. Note that the second element-containing gas is activated by heat and supplied, so that a soft reaction can be caused and the reforming can be performed softly.

Hereinafter, the processing sequence of this embodiment will be specifically described. Here, the first element is silicon (Si), the second element is nitrogen (N), the first element-containing gas is a DCS gas that is a silicon-containing gas, and the second element-containing gas is a nitrogen-containing gas. An example of forming a silicon nitride film (SiN film) as an insulating film on a substrate using NH ₃ gas and the sequence of FIG. 3 will be described. In this example, the first gas supply system constitutes a silicon-containing gas supply system (first element-containing gas supply system), and the second gas supply system constitutes a nitrogen-containing gas supply system (second element-containing gas supply system). Is configured.

  When a plurality of wafers 200 are loaded into the boat 217 (wafer charge), as shown in FIG. 1, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and processed in the processing chamber 201. It is carried in (boat loading). In this state, the seal cap 219 seals the lower end of the reaction tube 203 via the O-ring 220.

  The processing chamber 201 is evacuated by a vacuum pump 246 so that a desired pressure (degree of vacuum) is obtained. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure (pressure adjustment). Further, the processing chamber 201 is heated by the heater 207 so as to have a desired temperature. At this time, the power supply to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the inside of the processing chamber 201 has a desired temperature distribution (temperature adjustment). Subsequently, the boat 217 is rotated by the rotation mechanism 267, whereby the wafer 200 is rotated (wafer rotation). Thereafter, two steps to be described later are sequentially executed.

[Step 1]
The valve 243a of the first gas supply pipe 232a is opened, and DCS gas is caused to flow into the first gas supply pipe 232a. The flow rate of the DCS gas that has flowed through the first gas supply pipe 232a is adjusted by the mass flow controller 241a. The flow-adjusted DCS gas is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 from the gas supply hole 250a of the first nozzle 249a. At this time, the valve 243e is opened at the same time, and an inert gas such as N ₂ gas is allowed to flow into the inert gas supply pipe 232e. The flow rate of the N ₂ gas flowing through the inert gas supply pipe 232e is adjusted by the mass flow controller 241e. The N ₂ gas whose flow rate has been adjusted is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 together with the DCS gas.

  At this time, the APC valve 244 is appropriately adjusted so that the pressure in the processing chamber 201 is, for example, in the range of 10 to 1000 Pa. The supply flow rate of the DCS gas controlled by the mass flow controller 241a is, for example, a flow rate in the range of 10 to 1000 sccm. The time during which the DCS gas is exposed to the wafer 200, that is, the gas supply time (irradiation time) is, for example, a time within the range of 2 to 120 seconds. At this time, the temperature of the heater 207 is set to such a temperature that the CVD reaction occurs in the processing chamber 201, that is, the temperature of the wafer 200 is, for example, a temperature in the range of 300 to 650 ° C. Note that when the temperature of the wafer 200 is less than 300 ° C., DCS is hardly adsorbed on the wafer 200. Further, when the temperature of the wafer 200 exceeds 650 ° C., the CVD reaction becomes strong, and the uniformity tends to deteriorate. Therefore, the temperature of the wafer 200 is preferably set to a temperature within the range of 300 to 650 ° C.

  By supplying the DCS gas, a first layer containing silicon as the first element is formed on the base film on the surface of the wafer 200. That is, a silicon layer (Si layer) as a silicon-containing layer of less than one atomic layer to several atomic layers is formed on the wafer 200 (on the base film). The silicon-containing layer may be a chemical adsorption layer of DCS. Silicon is an element that becomes a solid by itself. Here, the silicon layer includes a continuous layer made of silicon, a discontinuous layer, and a thin film formed by overlapping these layers. A continuous layer made of silicon may be referred to as a thin film. The DCS chemical adsorption layer includes a continuous chemical adsorption layer of DCS molecules and a discontinuous chemical adsorption layer. When the thickness of the silicon-containing layer formed on the wafer 200 exceeds several atomic layers, the nitriding action in Step 2 described later does not reach the entire silicon-containing layer. The minimum value of the silicon-containing layer that can be formed on the wafer 200 is less than one atomic layer. Therefore, the thickness of the silicon-containing layer is preferably less than one atomic layer to several atomic layers. Note that, under the condition that the DCS gas self-decomposes, silicon is deposited on the wafer 200 to form a silicon layer. Under the condition that the DCS gas does not self-decompose, the DCS is chemically adsorbed on the wafer 200 to cause DCS. A chemisorbed layer is formed. In addition, it is preferable to form a silicon layer on the wafer 200 in order to increase the film formation rate, rather than to form a DCS chemical adsorption layer on the wafer 200.

After the silicon-containing layer is formed, the valve 243a is closed and the supply of DCS gas is stopped. At this time, the DCS after the APC valve 244 of the gas exhaust pipe 231 is kept open and the processing chamber 201 is evacuated by the vacuum pump 246 to contribute to the formation of unreacted or silicon-containing layer remaining in the processing chamber 201. The gas is removed from the processing chamber 201. At this time, the valve 243e is kept open and the supply of N ₂ gas into the processing chamber 201 is maintained. This enhances the effect of removing unreacted or residual DCS gas remaining in the processing chamber 201 from the processing chamber 201.

As the silicon-containing gas, not only DCS gas but also inorganic raw materials such as tetrachlorosilane (SiCl ₄ , abbreviation: TCS) gas, hexachlorodisilane (Si ₂ Cl ₆ , abbreviation: HCD) gas, monosilane (SiH ₄ ) gas, etc. Aminosilane-based tetrakisdimethylaminosilane (Si (N (CH ₃ ) ₂ ) ₄ , abbreviation: 4DMAS) gas, trisdimethylaminosilane (Si (N (CH ₃ ) ₂ ) ₃ H, abbreviation: 3DMAS) gas, bisdiethylaminosilane Organic raw materials such as (Si (N (C ₂ H ₅ ) ₂ ) ₂ H ₂ , abbreviation: 2DEAS) gas, bistally butylaminosilane (SiH ₂ (NH (C ₄ H ₉ )) ₂ , abbreviation: BTBAS) gas It may be used. As the inert gas, a rare gas such as Ar gas, He gas, Ne gas, or Xe gas may be used in addition to N ₂ gas.

[Step 2]
After the residual gas in the processing chamber 201 is removed, the valve 243d of the second gas supply pipe 232d is opened, and NH ₃ gas is caused to flow into the second gas supply pipe 232d. The flow rate of the NH ₃ gas flowing through the second gas supply pipe 232d is adjusted by the mass flow controller 241d. The NH ₃ gas whose flow rate has been adjusted is supplied into the buffer chamber 237 from the gas supply hole 250d of the second nozzle 249d. At this time, NH ₃ gas supplied into the buffer chamber 237 is plasma-excited by applying high-frequency power from the high-frequency power source 273 via the matching unit 272 between the first rod-shaped electrode 269 and the second rod-shaped electrode 270. Then, the active species is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 from the gas supply hole 250e. At the same time, the valve 243h is opened and N ₂ gas is allowed to flow into the inert gas supply pipe 232h. The N ₂ gas is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 together with the NH ₃ gas.

When flowing NH ₃ gas as active species by plasma excitation, the APC valve 244 is appropriately adjusted to set the pressure in the processing chamber 201 to a pressure in the range of 10 to 100 Pa, for example. The supply flow rate of NH ₃ gas controlled by the mass flow controller 241d is, for example, a flow rate in the range of 100 to 10,000 sccm. The time during which the wafer 200 is exposed to the active species obtained by plasma excitation of NH ₃ gas, that is, the gas supply time (irradiation time) is, for example, a time within the range of 2 to 120 seconds. The temperature of the heater 207 at this time is set to a temperature at which the temperature of the wafer 200 becomes a temperature within the range of 300 to 650 ° C. as in Step 1. In addition, the high frequency power applied between the 1st rod-shaped electrode 269 and the 2nd rod-shaped electrode 270 from the high frequency power supply 273 is set so that it may become the electric power within the range of 50-1000W, for example. NH ₃ gas has a high reaction temperature, and it is difficult to react at the wafer temperature and the processing chamber pressure as described above. Therefore, the NH ₃ gas is made to flow after being activated by plasma excitation. Therefore, the temperature of the wafer 200 is as described above. The low temperature range set in (2) may be maintained. Also, without plasma excitation in supplying NH ₃ gas, by a pressure in the range of pressures, for example 50~3000Pa in the APC valve 244 is appropriately adjusted to the process chamber 201, non NH ₃ gas Thermal activation with plasma is also possible. Note that the NH ₃ gas activated by heat and supplied can cause a soft reaction, and nitriding described later can be performed softly.

At this time, the gas flowing in the processing chamber 201 is activated species obtained by plasma-exciting NH ₃ gas, or NH ₃ gas that is thermally activated by increasing the pressure in the processing chamber 201. There is no DCS gas flowing in the processing chamber 201. Therefore, NH ₃ gas does not cause a gas phase reaction became active species, or activated NH ₃ gas, the silicon-containing layer as a first layer formed on the wafer 200 in Step 1 React with. As a result, the silicon-containing layer is nitrided and modified into a second layer containing silicon (first element) and nitrogen (second element), that is, a silicon nitride layer (SiN layer).

Thereafter, the valve 243d of the second gas supply pipe 232d is closed to stop the supply of NH ₃ gas. At this time, the APC valve 244 of the gas exhaust pipe 231 is kept open, the processing chamber 201 is evacuated by the vacuum pump 246, and the NH ₃ gas remaining in the processing chamber 201 and contributing to nitridation is removed. Excluded from the processing chamber 201. At this time, the valve 243h is kept open and the supply of N ₂ gas into the processing chamber 201 is maintained. This enhances the effect of removing NH ₃ gas remaining in the processing chamber 201 and remaining unreacted or contributed to nitridation from the processing chamber 201.

As the nitrogen-containing gas, in addition to a gas in which NH ₃ gas is excited by plasma or heat, a gas in which N ₂ gas, NF ₃ gas, N ₃ H ₈ gas or the like is excited by plasma or heat may be used. A gas obtained by diluting a gas with a rare gas such as Ar gas, He gas, Ne gas, or Xe gas may be excited with plasma or heat.

  By performing steps 1 and 2 described above as one cycle and performing this cycle at least once, a thin film containing silicon (first element) and nitrogen (second element) with a predetermined thickness on the wafer 200, that is, silicon A nitride film (SiN film) can be formed. The above cycle is preferably repeated a plurality of times.

When a film forming process for forming a silicon nitride film having a predetermined thickness is performed, an inert gas such as N ₂ is exhausted while being supplied into the process chamber 201, whereby the inside of the process chamber 201 is purged with the inert gas. (Gas purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

  Thereafter, the seal cap 219 is lowered by the boat elevator 115, the lower end of the reaction tube 203 is opened, and the processed wafer 200 is supported by the boat 217 from the lower end of the reaction tube 203 to the outside of the reaction tube 203. Unload (boat unload). Thereafter, the processed wafer 200 is taken out from the boat 217 (wafer discharge).

  Here, as a specific example of the processing sequence of this embodiment, an example in which a SiN film is formed using a silicon-containing gas and a nitrogen-containing gas as the first element-containing gas and the second element-containing gas has been described. The invention is not limited to the specific examples described above, and various modifications can be made without departing from the scope of the invention.

  For example, when an aluminum nitride film (AlN film) is formed using an aluminum-containing gas and a nitrogen-containing gas as the first element-containing gas and the second element-containing gas, respectively, or as the first element-containing gas and the second element-containing gas When a titanium nitride film (TiN film) is formed using a titanium-containing gas and a nitrogen-containing gas, respectively, or a boron-containing gas and a nitrogen-containing gas are used as the first element-containing gas and the second element-containing gas, respectively. The present invention can also be applied to the case where a (BN film) is formed. Further, for example, when a silicon oxide film (SiO film) is formed using a silicon-containing gas and an oxygen-containing gas as the first element-containing gas and the second element-containing gas, respectively, or when the first element-containing gas and the second element-containing gas are formed. When using an aluminum-containing gas and an oxygen-containing gas as the gas to form an aluminum oxide film (AlO film), a titanium-containing gas and an oxygen-containing gas are used as the first element-containing gas and the second element-containing gas, respectively. The present invention can also be applied when an oxide film (TiO film) is formed. Further, for example, the present invention can be applied to the case where a silicon carbide film (SiC film) is formed by using a silicon-containing gas and a carbon-containing gas as the first element-containing gas and the second element-containing gas, respectively.

As the aluminum-containing gas, for example, trimethylaluminum (Al (CH ₃ ) ₃ , abbreviation: TMA) gas can be used. As the titanium-containing gas, for example, titanium tetrachloride (TiCl ₄ ) gas or tetrakisdimethylamino titanium (Ti [N (CH ₃ ) ₂ ] ₄ , abbreviation: TDMAT) gas can be used. As the boron-containing gas, for example, boron trichloride (BCl ₃ ) gas or diborane (B ₂ H ₆ ) gas can be used. As the carbon-containing gas, for example, propylene (C ₃ H ₆ ) gas or ethylene (C ₂ H ₄ ) gas can be used. As the oxygen-containing gas, for example, oxygen (O ₂ ) gas, ozone (O ₃ ) gas, nitrogen monoxide (NO) gas, nitrous oxide (N ₂ O) gas, and water vapor (H ₂ O) can be used. .

  As described above, in the processing sequence of this embodiment, as the first element, for example, a semiconductor element such as silicon (Si) or boron (B) or a metal element such as aluminum (Al) or titanium (Ti) is used. As the second element, elements such as nitrogen (N), carbon (C), and oxygen (O) can be used.

By the way, in the above vertical processing furnace, high frequency noise is generated by plasma generation, and the generated high frequency noise may cause malfunction of the electrical equipment.
Therefore, in the present embodiment, the configuration shown in FIGS. 4 and 5 prevents high-frequency noise from leaking through the wiring of the heater and the temperature sensor.

As shown in FIG. 4, a heater power supply line 208 that supplies electric power is connected to the heater 207. A noise removal filter 212 for removing high frequency noise 213 generated by plasma is connected to the heater power line 208. The noise removal filter 212 is installed at a position away from the heater 207 due to heat resistance limitations.
As shown in FIGS. 5A and 5B, the heater power line 208 has a configuration in which the conductive wiring 209 is covered with an insulating wiring covering member 210. A shield member 211 that shields high-frequency noise generated by plasma is incorporated. The shield member 211 is provided so as to entirely cover the conductive wiring 209 and is provided inside the wiring covering member 210. The shield member 211 is incorporated in a wiring covering member 210 provided between the heater 207 and the noise removal filter 212. A ground wire 214 is connected to the shield member 211.

As shown in FIG. 4, a thermocouple 263 is used as a temperature sensor, a compensation lead 264 is connected to the thermocouple 263, and high frequency noise 213 generated by plasma is removed from the compensation lead 264. A noise removal filter 262 is connected. Note that the noise removal filter 262 is installed at a position away from the heater 207 due to heat resistance limitations.
As shown in FIG. 5C, the compensation conductor 264 has a configuration in which a conductive wiring 265 is covered with an insulating wiring covering member 266, and the wiring covering member 266 has a high frequency generated by plasma. A shield member 268 that shields noise is incorporated. The shield member 268 is provided so as to entirely cover the conductive wiring 265 and is provided inside the wiring covering member 266. The shield member 268 is incorporated in the wiring covering member 266 between the thermocouple 263 and the noise removal filter 262. A ground wire 261 is connected to the shield member 268.

  According to this embodiment, the following operations and effects are achieved.

(1) By incorporating a shield member into the wiring covering member of the heater power supply line, high frequency noise can be prevented from leaking out as electromagnetic waves from the heater power supply line, thereby preventing malfunction of electrical equipment. be able to.

(2) By incorporating the shield member into the heater power line, there is no gap or bulkiness at the end, unlike when the shield material is covered or wound.

(3) By connecting a noise removal filter to the heater power supply line, it is possible to prevent high-frequency noise generated by plasma generation from being transmitted to the electrical equipment connected to the heater power supply line. Can be prevented.

(4) The noise removal filter must be installed at a position away from the heater due to heat resistance restrictions, and high-frequency noise may have leaked from the section between the heater power supply line and the noise removal filter. In this embodiment, by incorporating a shield member in the wiring covering member of the heater power supply line provided between the heater and the noise removal filter, it is possible to prevent high frequency noise from leaking from the section. Can do.

(5) Since the shield member is incorporated in the wiring covering member of the compensation lead wire, high frequency noise can be prevented from leaking to the surroundings as electromagnetic waves from the compensation lead wire, so that malfunction of electrical equipment can be prevented.

(6) By incorporating the shield member inside the compensating conductor, there is no gap or bulkiness at the end, unlike when the shield material is covered or wrapped.

(7) By connecting a noise removal filter to the compensation lead, it is possible to prevent high-frequency noise generated by plasma generation from being transmitted to the electrical equipment connected to the compensation lead, thus preventing malfunction of the electrical equipment. Can do.

(8) By incorporating the shield member into the wiring covering member of the compensation conductor provided between the heater and the noise removal filter, high frequency noise leaks from the section between the heater of the compensation conductor and the noise removal filter. Can be prevented.

(9) Since it is not necessary to shield high-frequency noise by sheet metal or wire mesh, or to wrap a shield material around the wiring, omit the use of a large amount of screws and conductive packing to ensure high sealing performance. Can do.

  Needless to say, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, the temperature sensor is not limited to using a thermocouple.

  The shield member for the temperature sensor compensating conductor may be omitted, or the shield member for the heater power supply line may be omitted.

  The noise removal filter for the temperature sensor compensating conductor may be omitted, or the noise removal filter for the heater power supply line may be omitted.

  Although the batch type vertical hot wall type plasma apparatus has been described in the above embodiment, the present invention can be applied to a plasma processing apparatus using electron beam excited plasma, and also to a single wafer type plasma processing apparatus. can do.

  In the above embodiment, the case where the wafer is processed has been described. However, the processing target may be a photomask, a printed wiring board, a liquid crystal panel, a compact disk, a magnetic disk, or the like.

Hereinafter, preferred embodiments of the present invention will be additionally described.
According to one aspect of the present invention, the following substrate processing apparatus is provided.
A processing chamber for processing the substrate;
A gas supply system for supplying gas into the processing chamber;
A plasma source for activating the gas supplied from the gas supply system with plasma;
A heater for heating the substrate in the processing chamber;
A temperature sensor for measuring the temperature in the processing chamber;
A heater power line connected to the heater;
A temperature sensor compensating lead wire connected to the temperature sensor;
The heater power line and the temperature sensor compensation conductor have a configuration in which conductive wiring is covered with an insulating wiring covering member, and the heater power line and / or the temperature sensor compensation conductor A substrate processing apparatus, wherein a shield member that shields high-frequency noise generated by the plasma is incorporated in the wiring covering member.
Preferably, the shield member is provided so as to entirely cover the wiring.
Preferably, the shield member is provided inside the wiring covering member so as to entirely cover the wiring.
Preferably, a noise removal filter for removing high frequency noise generated by the plasma is connected to the heater power line, and the shield member is provided between the heater and the noise removal filter. The heater power supply line is incorporated in the wiring covering member.
Preferably, a noise removal filter for removing high-frequency noise generated by the plasma is connected to the temperature sensor compensation lead wire, and the shield member is provided between the temperature sensor and the noise removal filter. The temperature sensor compensation lead wire is incorporated in the wiring covering member.

201 ... processing chamber,
232a ... first gas supply pipe, 241a ... mass flow controller, 243a ... valve, 249a ... first nozzle (first gas supply system), 232e ... first inert gas supply pipe, 241e ... mass flow controller, 243e ... valve (first) 1 inert gas supply system),
232d ... second gas supply pipe, 241d ... mass flow controller, 243d ... valve, 249d ... second nozzle, 237 ... buffer chamber (second gas supply system), 232h ... second inert gas supply pipe, 241h ... mass flow controller, 243h ... valve (second inert gas supply system),
269 ... 1st rod-shaped electrode, 270 ... 2nd rod-shaped electrode, 275 ... Electrode protective tube, 272 ... Matching device, 273 ... High frequency power supply (plasma source),
207 ... heater, 208 ... heater power line, 209 ... conductive wiring, 210 ... wiring covering member, 211 ... shield member, 212 ... noise removal filter, 213 ... high frequency noise, 214 ... ground wire,
261 ... Ground wire, 262 ... Noise removal filter, 263 ... Thermocouple (temperature sensor), 264 ... Compensation lead for temperature sensor, 265 ... Conductive wiring, 266 ... Wiring covering member, 268 ... Shield member.

Claims (1)

A processing chamber for processing the substrate;
A gas supply system for supplying gas into the processing chamber;
A plasma source for activating the gas supplied from the gas supply system with plasma;
A heater for heating the substrate in the processing chamber;
A temperature sensor for measuring the temperature in the processing chamber;
A heater power line connected to the heater;
A temperature sensor compensating lead wire connected to the temperature sensor;
The heater power line and the temperature sensor compensating lead have a configuration in which conductive wiring is covered with an insulating wiring covering member, and the heater power line and / or the temperature sensor compensating lead A substrate processing apparatus, wherein a shield member that shields high-frequency noise generated by the plasma is incorporated in the wiring covering member.

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