TWI757447B - Method and apparatus for thermally treating substrates - Google Patents

Abstract

The invention relates to a method and a device for the thermal treatment of at least one substrate (2) at a controlled temperature in a process chamber (1) of a processing device by means of a heat flow from which thermal power (10) is supplied from the outside The heating element ( 5 ) heated by the substrate holder ( 4 ) is sent through the substrate ( 2 ) heated by the substrate holder ( 4 ) and the process chamber ( 1 ) to conduct the waste heat flow ( 26 ) to the top of the process chamber (7) Cooling element (9) for cooling. The temperature control system has at least one control loop in which the waste heat flow (26) is the control variable, wherein the heat flow is measured through a heat flow detection member (20). In order to control the heat flow, the variable heat flow resistance is changed.

Description

Method and apparatus for thermally treating substrates

The present invention relates to a method and an apparatus for thermally treating at least one substrate at a controlled temperature in a process chamber of a processing apparatus by means of a heat flow from a heating element which is supplied with thermal power from the outside and heats the substrate holder Departures pass through the substrate heated by the substrate holder and the process chamber to a cooling element that conducts the waste heat flow outwards and cools the top of the process chamber.

Devices of the same type are used in semiconductor technology to coat substrates with layers, in particular semiconductor layers. The substrate is abutted on the substrate holder or the substrate holder carried by the substrate holder and rotatable around the axis. Energy is applied to the substrate holder from the side facing away from the substrate. The heating elements provided for this can be infrared radiators or RF coils. The surface of the substrate to be coated faces the process chamber, into which the process gas, which is at least partially decomposed after the chemical reaction, is fed so that layers can be produced on the surface of the substrate. The top of the process chamber opposite the substrate is cooled to a temperature well below the temperature of the substrate seat by means of a cooling element. Based on this temperature difference, a heat flow is formed from the substrate seat through the substrate and the process chamber to the top of the process chamber cooled by the cooling element. This heat flow depends on the heat transfer characteristics of the elements of the processing device disposed between the heating element and the cooling element, wherein the heat transfer from the substrate holder to the substrate during the coating process, with the process parameters remaining substantially constant The characteristics remain essentially the same. The thermal conductivity of the heat transport path from the substrate holder to the substrate surface is essentially determined by the thermal conductivity of the solid, where, in the case of rotating the substrate holder on an air cushion, heat transfer through the air gap also needs to be taken into account. The changing airflow also results in changes in heat transport. This air gap typically, together with the air gap between the substrate and the substrate holder, forms the greatest resistance to heat transport between the substrate holder and the substrate.

The heat transfer from the surface of the substrate through the process chamber to the top of the process chamber takes place on the one hand by thermal conduction by means of the gas located in the process chamber, and to a lesser extent also by convection, but substantially by thermal radiation, and depends on Emissivity and reflectivity of surfaces at the top of the substrate and process chamber. In particular, the surface of the top of the process chamber has a time-varying emissivity. This is a consequence of parasitic coating of the top surface of the process chamber, but also a consequence of aging.

The purpose of temperature control is to maintain the temperature of the chemically reactive surface of the substrate at a constant value, wherein the substrate surface should have the same temperature as possible over its entire surface, and this temperature must be maintained throughout the coating process and It remains constant in subsequent coating procedures. In order to measure the surface temperature, pyrometers are used in the prior art, in particular pyrometers operating at a wavelength of 400 nm. By means of such a pyrometer, the surface temperature of the substrate and, as the case may be, also the surface temperature of the substrate holder are determined optically. In the case of using a silicon substrate, the surface temperature of the substrate can be determined by such a pyrometer. This solution cannot be achieved when a sapphire substrate is used. Sapphire is transparent to light of this wavelength. If, for example, a GaN layer is deposited on a sapphire substrate, due to the transparency of the substrate, initially only the temperature of the surface of the substrate holder or substrate holder located below the substrate is measured by such a pyrometer. The surface temperature of the substrate or layers deposited on the substrate can be measured by pyrometers only if a sufficiently thick layer of GaN has been deposited on the substrate.

Therefore, in the heat transfer path between the heating element and the cooling element, there are several heat flow resistances along the direction of heat flow, the magnitude of which affects the temperature distribution between the heating element and the cooling element and the substrate temperature.

The purpose of the present invention is to improve the same type of method or the same type of device so that the same substrate temperature can be achieved with the same other process parameters in successive growth procedures.

The solution of the present invention to achieve the above object is the invention given in the scope of the patent application, wherein the subordinate items are not only the preferred further solutions of the invention given in the two parallel claims, but also the invention used to achieve the above purpose-built solution.

In a first aspect of the present invention, the variable heat flow resistance is changed. In this solution, in the heat transport path from the substrate holder to the cooling element, and in particular between the top of the process chamber and the cooling element, there is an element whose thermal conductivity, in particular the thermal conductivity, is variable. The element may be constructed of movable parts, eg movable solids. Preferably, however, the element is formed through a gap through which the flushing gas can flow. Heat must flow from the substrate holder to the cooling element through this gap, so the gap constitutes a heat flow resistance. This heat flow resistance can be varied by, for example, feeding gases of different thermal conductivity into the gap. In particular, the following solution is used: a mixture of two gases with significantly different thermal conductivity properties or heat capacities is fed into the gap. In particular, a mixture of hydrogen and nitrogen is fed into this gap. The mixing ratio of the two gases is changed in such a way that the heat flow out of the cooling element remains constant. At least two control loops can be provided in this solution. The first control loop controls the temperature of the substrate seat. Here, the substrate holder is preferably heated by an RF heating device. A temperature measuring element is arranged in the substrate holder or on the edge of the substrate holder. The temperature measuring element may be the end of the optical cable connected to the pyrometer. However, the temperature measuring element can also be a thermocouple, which provides a thermoelectromotive force used as a control variable for thermal power control. The temperature measurement can be performed on the side of the substrate holder facing the heating device. The second control loop regulates the waste heat flow to a nominal value. A heat flow detection means is also provided here, which determines the waste heat flow by means of the mass flow and temperature of the coolant or the temperature difference between the inlet temperature and the outlet temperature, which is kept constant by the second control loop. The flush gas flushed gap extends parallel to the substrate seat surface or the top of the process chamber over substantially the entire area of the process chamber where the substrate is located. The gas mixture in the gap can be changed by the air flow controller so that the waste heat flow of the coolant is kept constant. Thermal power is controlled by a heating element control system. The gap between the cooling element and the top of the process chamber can be in the millimeter range. Due to manufacturing tolerances, the gap width may vary in the case of replacing the top of the process chamber with another. The effects of such tolerances are also compensated for by the method of the present invention as temperature equilibration. It is also possible to compensate for changes in the emissivity of the surface defining the gap. The gap preferably extends between the cooling element and the top of the process chamber that defines the process chamber. However, the present invention also proposes that working parameters representing heat flow characteristics are also used in the temperature control process. According to the invention, the temperature control is influenced by the heat flow. According to another aspect of the present invention, the present invention proposes that the temperature control device has at least one control loop, wherein the heat flow is the control variable. In the method of the invention, thermal power is supplied from the outside to the heating element. The heating element heats the substrate holder. The heat flow from the heating element to the cooling element is formed based on the temperature difference between the substrate holder and the cooling element. The heat flow passes through the substrate heated by the substrate holder and the process chamber until it reaches the cooling element that cools the top of the process chamber. According to the present invention, a heat flow detection member is provided for measuring the heat flow at a predetermined position. In a preferred embodiment of the invention, the waste heat flow is measured and used for temperature control. For this purpose, the device of the invention has an electronic control device, which is arranged and programmed so that the control parameters determined from the heat dissipated by the coolant are used for temperature control. In particular, the cooling element has cooling channels through which the coolant passes. The coolant can be maintained at a constant cooling temperature by means of the cooling control loop. However, it is sufficient to use only the following preferred solution: A constant mass flow of coolant flows through the cooling channels. The mass flow of the coolant and the difference between the exit and entry temperatures of the coolant together serve as a measure for heat dissipation. The product of these two variables and the specific heat capacity of the coolant constitute the measured waste heat flow. It is also possible to vary the mass flow, for example to keep the discharge temperature of the coolant at a constant value. According to one aspect of the invention, the waste heat flow is preferably used here as a control variable at a constant coolant flow, thereby maintaining the temperature of the substrate at a constant value. According to one solution, the rated temperature is first maintained at a constant value, or the thermal power required to obtain the rated temperature is observed. If the thermal power is found to increase relative to the reference value, the temperature rating can be increased. According to one approach, as an alternative to thermal power, the difference in waste heat flow may be used to determine the nominal temperature compensation. In this solution, the heat flow constitutes at least one control variable of the heating element control loop. This solution is used at least during times when a reliable value of the substrate surface temperature cannot be determined by means of another, in particular optical, temperature measuring instrument. However, if the conditions permit optical measurement of the substrate surface temperature, the thermal power can also be adjusted according to the rated value of the substrate temperature. This solution applies in particular to processing devices in which one or several substrates are placed against a substrate holder, which is heated from the back side by means of a resistance heating device or by means of an IR heating device. Particularly in this solution, the process gas is preferably introduced into the process chamber constructed as a shower head through the gas inlet member. The shower head has an exhaust plate, which extends parallel to the surface of the substrate base facing the process chamber and has several ventilation holes for the process gas to flow into the process chamber. The shower head is both the top of the process chamber and the cooling element, but can also be in contact with the top of the process chamber. The showerhead has cooling channels through which coolant flows. The device or the method may have several control loops that cooperate with each other. In order to prevent the coolant from being heated to impermissible temperatures, a cooling element control circuit is provided. In the coolant control loop, the temperature of the coolant and especially the discharge temperature of the coolant can be kept at a constant value by varying the mass flow of the coolant. But it is sufficient only to measure the temperature difference between the inlet temperature and the outlet temperature with a constant mass flow of waste heat flow. To control this temperature difference for the rated value, the thermal power can be varied. This is done by means of a heating element control loop with waste heat flow acting as a control variable. According to another aspect of the present invention, wherein temperature control is effected by heat flow, the rating of the heating controller for controlling the thermal power is the surface temperature measured on the substrate and/or the substrate holder. This surface temperature can be measured optically by means of a pyrometer. In particular, the electronic control device, which is a component of the control device, receives the setpoint value for controlling the surface temperature from the setpoint value setting device, which in turn obtains the setpoint value from a recipe programmed in the control system. In this approach, the temperature of the top of the process chamber is explicitly maintained at a specific temperature by the flushing gas composition, eg to ensure the desired chemical pre-reaction. In this case, variations in surface emissivity due to process deposition result in a deviation of the substrate temperature from the target value, which is compensated for by correcting the heater rating. The control device continuously or at time intervals determines the heat flow and in particular the waste heat flow, in which the heat flow of the coolant is determined. If the heat flow deviates, for example, from a preset value determined in a growth program "Golden Run" carried out under standard conditions, the rated value for the surface temperature of the substrate or substrate holder is modified by means of the rated value setting device . Especially when the degree of change of the heat flow relative to the standard heat flow reaches a preset value, the rated value of the surface temperature is adjusted. Aging effects or overlay effects on the top of the process chamber can be compensated for by rating adjustments or subsequent corrections. Ability to respond to long-term drift. For this aspect of the invention, where the layer thickness or the physical properties of the layer do not allow optical determination of the temperature of the layer, it is also possible, depending on the situation, only for a short period of time by means of the variable pair derived from the heat flow difference. The rating of the heating control device is corrected. This makes it possible, for example, to determine the current waste heat flow during the deposition of layers whose temperature can be measured well by means of a pyrometer, and thus to use this waste heat flow as a reference during the deposition of earlier layers of the subsequent process that do not support optical temperature determination. value. The heat flow of the completed deposition process can also be used as a reference value.

1‧‧‧Process Room

2‧‧‧Substrate

3‧‧‧Substrate holder

4‧‧‧Substrate holder

5‧‧‧Heating elements, heating devices

6‧‧‧Substrate base temperature

6'‧‧‧Substrate temperature

7‧‧‧Top of process room

8‧‧‧clearance

9‧‧‧Exhaust plate

9'‧‧‧cooling element

10‧‧‧thermal power

11‧‧‧Heating device controller

12‧‧‧Temperature measurement

13‧‧‧Cooling channel

14‧‧‧Import

15‧‧‧Export

16‧‧‧Thermometer

17‧‧‧Grooving

18‧‧‧Air Cushion

19‧‧‧Cover

20‧‧‧Heat flow measuring device

21‧‧‧Gas flow controller

22‧‧‧Inflow of nitrogen

23‧‧‧Hydrogen inflow

24‧‧‧Exhaust port

25‧‧‧Correction

26‧‧‧Waste heat flow

27‧‧‧Throttle valve

28‧‧‧Rating value setting device

29‧‧‧Rated value

Rt1‧‧‧Heat flow resistance

Rt2‧‧‧Heat flow resistance

Rt3‧‧‧Heat flow resistance

Embodiments of the present invention will be described below with reference to the accompanying drawings. Among them: FIG. 1 is a schematic cross-sectional view of the process chamber of the processing device of the first embodiment, FIG. 2 is a block diagram of the heat flow route from the heating device 5 to the cooling element 9 of the first embodiment, and FIG. 3 is the first embodiment. A schematic diagram similar to FIG. 1 of the second embodiment, and FIG. 4 is a schematic diagram similar to FIG. 2 of the second embodiment.

Figure 1 shows, in a substantially schematic manner, a cross-section of a process chamber of a CVD reactor as described, for example, in DE 10 2006 013 801 and the publications cited in that case. The apparatus is used to deposit III-V semiconductor layers on a substrate. For this purpose, a mixture of two or more process gases is fed together with a carrier gas into a gas inlet member in the form of a shower head. The process gases may be hydrides of elements of main group V and organometallic compounds of elements of main group III. For example, trimethylgallium can be fed with ammonia into a process chamber where the III-V is deposited on one of the III-V substrates, but preferably on a silicon or sapphire substrate, to produce a GaN layer layer. The decomposition reaction of the process gas takes place not only on the surface of the heated substrate 2 but also on the side of the exhaust plate of the shower head facing the process chamber 1 . The exhaust plate forms the top 7 of the process chamber. The exhaust plate 9 has exhaust openings 24, which are arranged in the shape of a shower head. The cooling passages 13 through which the coolant passes extend between the exhaust ports 24 . The gas inlet member constituting the cooling element 9, the IR heating device 5, the substrate holder for supporting the substrate 2 provided between the shower head 9 and the IR heating device 5 are located in the hermetically sealed reactor chamber of the CVD reactor.

Element symbol 6 denotes a measurement point, at which the surface temperature of the substrate holder 4 can be measured. This is done by means of a temperature measuring device, wherein the temperature measuring device may be a pyrometer. The pyrometer is arranged in the reactor housing outside the process room and is capable of optically measuring the surface temperature of the substrate 2 and providing a temperature measurement 12 that is fed to a heating device controller 11, which is capable of this The temperature measurements are used as control variables for feeding thermal power 10 into the heating element 5 to heat the substrate holder 4 and in particular the surface of the substrate 2 to the process temperature. In addition, a measuring point 6 ′ may be provided for determining the surface temperature of the substrate 2 . For example, the temperature measured there can be used for setpoint adjustment.

The cooling liquid is fed into the cooling channel 13 through the inlet 14 , passes through the cooling channel and leaves the cooling channel 13 through the outlet 15 . The temperature of the cooling liquid leaving the cooling channel 13 can be measured by the thermometer 16 . Measure the temperature difference between the measured value of the coolant's discharge temperature and the coolant's incoming temperature.

The heat flow through the cooling water and flowing out from the cooling element 9 through the outlet 15 can be measured by the heat flow measuring device 20 . The temperature measured by the thermometer 16 can be used for this. The waste heat flow is indicated by the reference numeral 26 .

Rt1 represents the first heat flow resistance, which is affected by the thermal conductivity of the substrate 2 and the thermal resistance between the substrate 2 and the substrate holder. With the rest of the process parameters unchanged, this heat flow resistance Rt1 remains substantially unchanged during the coating process.

Rt2 represents the second heat flow resistance, which represents the heat transfer path between the substrate surface and the top 7 of the process chamber, ie, and the bottom side of the cooling element 9 . The heat flow through the first heat flow resistance Rt1 is substantially realized through heat conduction. The heat flow through the second heat flow resistance Rt2 is achieved substantially by thermal radiation and depends on the emissivity of the substrate 2 and the surface of the chamber roof 7 or the wall of the cooling element 9 facing the chamber 1 . This emissivity varies during the implementation of the coating method for a number of reasons. First the surface may be aged for a while. But it is also important to create a coating on the surface, which affects optical properties such as emissivity and reflectivity. Thus, these characteristics of the process chamber change even if the rest of the process parameters, which are set substantially according to the recipe used, remain constant.

As the second heat flow resistance Rt2 changes, the temperature of the substrate surface may change.

When the substrate 2 is transparent to the wavelength used (for example, a sapphire substrate is transparent to 400 nm light), the surface temperature of the substrate 2 cannot be measured by a pyrometer in particular. During the deposition of the GaN layer on the sapphire substrate, the surface temperature of the substrate 2 or the layer can only be reliably measured when a sufficient layer thickness is achieved. Therefore, at the beginning of the growth of such a layer, not only is the temperature controlled by means of the temperature measurement 12, but also the nominal value is corrected by means of the control variable 25, which is influenced by the heat flow. This correction reflects the difference between the actual value of the waste heat flow 26 and the nominal value.

As an alternative to the deviation of the waste heat flow, the deviation of the thermal power from the desired reference value can also be used to derive the temperature correction. This is preferably done in a device having a setpoint value setting device 28 for changing the setpoint value 29 for the heating device controller 11 . The substrate holder temperature 6, in particular the temperature of the surface of the substrate holder 4 facing the process chamber, is measured by means of a temperature measuring device such as a pyrometer. This temperature constitutes the nominal value for the heating device controller 11 that controls the thermal power 10 . The surface temperature of the substrate holder 4 is controlled for the rated value 29 . The setpoint value 29 is set by the setpoint value setting device 28 . The setpoint value setting device 28 obtains the setpoint value 29 from an electronic control system that determines the setpoint value from a recipe.

The waste heat flow 26 is permanently measured by the heat flow measuring device 20 . If this waste heat flow deviates to a certain degree from the standard value within a certain period of time, the nominal value setting means 28 will change the nominal value 29, wherein the substrate temperature is increased or decreased. In this way it is possible to respond to the effects due to the coating on the top 7 of the process chamber. In general, thermal power can also be observed instead of waste heat.

However, when the substrate temperature 6 ′ can be measured, the substrate temperature may be sent to the rated value setting device 28 as the correction amount 25 .

FIG. 2 schematically shows the heat flow path from the heating element 10 through the two heat flow resistances Rt1 and Rt2 to the cooling element 9 . The waste heat flow 26 is measured by the heat flow measuring device 20 and compared to the nominal value. This results in a control variable 25 for controlling the heating device controller 11 whose manipulated variable is the thermal power 10 .

FIG. 3 schematically shows in cross-section the essential elements for the description of the invention of a CVD reactor constructed for example as described in DE 10 2009 003 624 A1 or DE 10 2006 018 514 A1.

The process gas flows into the process chamber 1 through a gas inlet member not shown in the figure. The process gas can also be a hydride of the main group V and an organometallic compound of the main group III. The process gas flows in with the carrier gas. The process gases react in the process chamber 1 , and in particular on the surface of the substrate 2 disposed in the process chamber 1 , to form III-V layers. As described for the first embodiment, the carrier gas and gaseous reaction products leave the process chamber 1 through the gas outlet, which is connected to a vacuum pump, so that a low pressure can be set in the process chamber 1 .

In the case of a substrate holder 4 whose temperature is optically measured through a measuring element, such as a thermocouple 6 or an optical cable, the substrate holder is heated from below by the heating device 5 . The heating device 5 may be an RF heating device, which generates eddy currents in the substrate holder 4 to inductively heat the substrate holder 4 . The temperature measurements 12 obtained by the measuring element 6 are sent to the heating device controller 11 , which supplies the heating power 10 with which the heating element 5 is operating as a manipulated variable.

The substrate holder 3 is in contact with the substrate holder 4 . The substrate holder 3 is located in the groove 17 on the air cushion 18 . The gas flowing into the air cushion 18 can rotate the substrate holder 3 about an axis. One or more substrates 2 are arranged on the substrate holder 3 .

With the same program parameters, the first heat flow resistance Rt1 changes substantially or only slightly during the coating process. However, if the program parameters are changed, the heat flow resistance Rt1 may also change. If the gas fed into the air gap forming the air cushion 18 changes in its heat transfer characteristics, then Rt1 also changes. The successive coating steps in the formulation are each carried out with different program parameters, since the layer sequence comprising the different layers is deposited one after the other. However, program steps at the same position in the same recipe have the same program parameters.

The process chamber 1 is bounded on the bottom side by the substrate 2 and on the top side by the process chamber top 7 , eg, made of graphite. The chamber top 7 is heated by the radiant heat emitted by the substrate frame 3 and the substrate 2 . The route between the substrate surface and the process chamber top 7 constitutes a second thermal flow resistance Rt2, which is affected by the optical properties of the surfaces of the substrate 2, the substrate frame 3 and the process chamber top 7. The emissivity, reflectivity and absorptivity of these surfaces vary with time, on the one hand due to natural aging, and on the other hand due to the coating in the coating procedure.

A gap 8 is formed between the top 7 of the process chamber and the bottom side of the wall formed by the cooling element 9, which is flushed by a flushing gas consisting of a mixture of two gases having mutually different thermal conductivities or heat capacities.

The cooling element 9 has cooling channels 13 into which inlets 14 feed coolant. The coolant heated in the cooling channel 13 leaves the cooling channel 13 through the outlet 15. The discharge temperature is measured by the thermometer 16 .

The waste heat flow 26 is measured by means of a heat flow measuring device 20 which is shown symbolically in FIG. 3 . This waste heat flow can be obtained from the heat capacity of the coolant, the mass flow rate, and the temperature difference between the inlet temperature and the outlet temperature.

A gas flow controller 21 is provided for controlling the gas flow of the two different gases entering the gap 8 . In particular, a gas flow controller 21 for controlling the inflow amount 22 of nitrogen gas and the inflow amount 23 of hydrogen gas into the gap 8 is provided. By adjusting the mixing ratio between hydrogen and nitrogen, the thermal conductivity in the gap 8 can be affected, thereby affecting the size of the third heat flow resistance Rt3. The changed heat flow resistance Rt2 can be compensated by changing the heat flow resistance Rt3. The change in heat flow resistance Rt3 is independent of component tolerances that affect the thermal properties of the gap 8 . Different gap heights, but also different emissivities of the surfaces defining the gap, can be compensated for by changing the gas composition.

In the embodiment shown in FIG. 3 , on the one hand, the first heat flow resistance Rt1 is determined by the air gap 18 and the thermal conductivity of the substrate frame 3 , the substrate 2 and the substrate holder 4 . On the other hand, in the region adjacent to the base plate 2 , the heat flow resistance is determined through the base plate holder 4 and the cover plate 19 resting on the base plate holder 4 .

FIG. 4 schematically shows the heat flow resistances Rt1 , Rt2 and Rt3 affecting the heat flow from the heating element 5 to the cooling element 9 , wherein the heat flow resistance Rt3 is a controllable heat flow resistance. It obtains the manipulated variable from a control loop whose control variable is the exhaust heat 26 . The latter is kept at a constant value by the controller 21 .

The equivalent circuit diagrams in Figures 2 and 4 greatly simplify the reflection of actual physical conditions. The heat flow generated by the heating device 5 only partially passes through the substrate holder 4 and the substrate holder 3 and through the substrate 2 . However, this part of the heat flow generated by the thermal power 10 can be regarded as constant in the observation, therefore, a substantially constant proportion of the thermal power 10 is taken as radiant heat from the surface of the substrate holder 3 and the surface of the substrate 2 into the process chamber 1 .

For physical reasons, the heat radiated by the substrate 2 and the substrate rack 3 also only partially reaches the top 7 of the process chamber. For physical reasons, the heat reaching the top 7 of the process chamber also only partially passes through the gap 8 to the cooling element 9 .

Preferably, the temperature of the substrate 2 and in particular the surface temperature of the substrate 2 is controlled to a substantially constant value by means of the device of the present invention and the method of the present invention, without explicitly measuring the temperature. According to the present invention, the thermodynamically relevant properties of the CVD reactor are controlled by the controller so as to maintain the heat flow, especially the waste heat flow 26, at a constant value. As examples, the embodiments show the effect of the thermal power of the heating element 5 and the effect of the additional heat flow resistance Rt3 in the heat transfer path between the heating element 5 and the cooling element 9 .

The controllers 11, 18, 21 may be separate electronic devices. However, these controllers 11, 18, 21 can also be constituted by an electronic, in particular programmed, control device. The controllers 11, 18, 21 may be PID controllers. In the embodiments shown in FIGS. 1 and 2 , the temperature measurement sensor 6 can also be used for temperature control, provided that the temperature measurement sensor can measure the substrate accurately enough in terms of process technology 2 the surface temperature. When the surface temperature of the substrate 2 cannot be measured accurately enough, the temperature is controlled by heat flow.

The foregoing embodiments are used to illustrate the inventions contained in the present application as a whole, and these inventions independently constitute improvements over the prior art through at least the following feature combinations, wherein two, several or All combined with each other, that is:

A method characterized in that temperature control is effected through heat flow.

A device characterized in that temperature control is effected through heat flow.

A method or a device, characterized in that the temperature control system has at least one control loop, wherein the heat flow is a control variable, or a changing heat flow results in a temperature setpoint correction.

A method or a device, characterized in that the heat flow is measured through the heat flow detection member 20 .

A method or a device, characterized in that the heat flow used in the correction of the temperature target value or in the temperature control is the waste heat flow 26 or the thermal power 10 .

A method or a device, characterized in that the cooling element 9 has a cooling channel 13 through which a coolant flows, which discharges waste heat to the outside by means of a mass flow, wherein the temperature difference of the coolant is determined for the determination of the waste heat flow 26 and its mass flow through the cooling channel 13 .

A method or a device, characterized in that, in order to control the heat flow, the thermal power 10 of the heating element 5 is varied.

A method or a device characterized in that, in order to control the heat flow, the variable heat flow resistance Rt3 is varied.

A method or a device, characterized in that, in order to control the heat flow, a mixture of gases of different thermal conductivity is fed into the gap 8 between the top 7 of the process chamber and the cooling element 9, wherein the mixing ratio is varied.

A method or a device, characterized in that the rated value 29 of the heating device controller 11 for controlling the thermal power 10 is the surface temperature measured on the substrate holder 4 or on the substrate 2, in the case of a change in heat flow, The setpoint value 29 is changed by the setpoint value setting device 28 .

A method or a device characterized in that the rated value 29 is changed when the degree of change of the integral determined by the permeation time of the deviation of the heat flow from a set standard value reaches a set amount.

All disclosed features (either as a single feature or as a combination of features) are essential to the invention. Therefore, the disclosure content of this application also includes all the content disclosed in the related/attached priority files (copy of the earlier application), and the features described in these files are also included in the patent scope of this application. The subordinate items describe the features of the improvement scheme of the present invention with respect to the prior art with its features, and its purpose is mainly to file a divisional application on the basis of these claims. Furthermore, the invention set forth in each claim may have one or more of the features set forth above, in particular by reference numerals and/or in the description of symbols. The invention also relates to embodiments in which individual ones of the aforementioned features are not implemented, especially if these are obviously superfluous for the particular purpose or can be replaced by technically equivalent means.

1‧‧‧Process Room

2‧‧‧Substrate

4‧‧‧Substrate holder

5‧‧‧Heating elements, heating devices

6‧‧‧Substrate base temperature

6'‧‧‧Substrate temperature

7‧‧‧Top of process room

9‧‧‧Exhaust plate

10‧‧‧thermal power

11‧‧‧Heating device controller

12‧‧‧Temperature measurement

13‧‧‧Cooling channel

14‧‧‧Import

15‧‧‧Export

16‧‧‧Thermometer

20‧‧‧Heat flow measuring device

24‧‧‧Exhaust port

25‧‧‧Correction

26‧‧‧Waste heat flow

28‧‧‧Rating value setting device

29‧‧‧Rated value

Rt1‧‧‧Heat flow resistance

Rt2‧‧‧Heat flow resistance

Claims (21)

A method of thermally treating at least one substrate at a controlled temperature in a process chamber of a processing apparatus by means of a heat flow from a heating element which is supplied with thermal power (10) from the outside and heats a substrate holder (4) (5) departure through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to the cooling element (9) which conducts the waste heat flow (26) outwards and cools the process chamber top (7) ), wherein the temperature control system has at least one control loop, wherein the heat flow is a control variable, characterized in that: in order to control the heat flow, the cooling element located on the substrate seat (4) or the top of the process chamber (7) and the cooling element are changed (9) Thermal conductivity of variable heat flow resistance in the heat transport route between. The method of claim 1, wherein the heat flow is measured through a heat flow detection member (20). The method of claim 1, wherein the heat flow used in temperature control is the waste heat flow (26) or the heat power (10). The method of claim 1 , wherein the cooling element ( 9 ) has cooling channels ( 13 ) for a coolant to pass through which conducts the waste heat to the outside through a mass flow, wherein in order to determine the waste heat flow ( 26 ) , measure the temperature difference of the coolant and its mass flow through the cooling channel (13). A method as claimed in claim 1, wherein, in order to control the heat flow, a mixture of gases of different thermal conductivity is fed into the gap (8) between the top (7) of the process chamber and the cooling element (9), wherein changing the mixing ratio. A device for thermally treating at least one substrate at a controlled temperature in a process chamber of the device by means of a heating element generated from a heatable element (5) as a result of an external input of thermal power (10) The heated substrate holder (4) passes through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to a cooling element which cools the top of the process chamber The heat flow up to the element (9), the cooling element (9) conducts the waste heat flow (26) to the outside, wherein the temperature control system has at least one control loop, wherein the heat flow is a control variable, characterized in that the substrate holder ( 4) or a heat transport route between the process chamber top (7) and the cooling element (9), wherein a variable heat flow resistance is located in the heat transport route, wherein the thermal conductivity of the heat flow resistance is variable. The device of claim 6, wherein the heat flow is measured through a heat flow detection member (20). 6. The apparatus of claim 6, wherein the heat flow used in temperature control is the waste heat flow (26) or the heat power (10). 6. Device according to claim 6, wherein the cooling element (9) has a cooling channel (13) for a coolant to pass through, the coolant dissipating the waste heat to the outside by mass flow, wherein in order to determine the waste heat flow (26) , measure the temperature difference of the coolant and its mass flow through the cooling channel (13). An apparatus as claimed in claim 6, wherein, in order to control the heat flow, a mixture of gases of different thermal conductivity is fed into the gap (8) between the top (7) of the process chamber and the cooling element (9), wherein changing the the mixing ratio. A method for thermally treating at least one substrate at a controlled temperature in a process chamber of a device by means of a heating element generated from a heatable element (5) as a result of an external input of thermal power (10) The heat flow from the heated substrate holder (4) through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to the cooling element (9) cooling the top of the process chamber, the cooling element ( 9) The waste heat flow (26) is led out, wherein a control loop regulates the actual temperature to the setpoint temperature, and wherein means for determining the heat flow are provided, characterized in that the change of the heat flow results in a difference between the temperature setpoints. Correction. The method of claim 11, wherein the heat flow used in the temperature rating correction is the waste heat flow (26) or the thermal power (10). A device for thermally treating at least one substrate at a controlled temperature in a process chamber of the device by means of a heating element generated from a heatable element (5) as a result of an external input of thermal power (10) The heat flow from the heated substrate holder (4) through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to the cooling element (9) cooling the top of the process chamber, the cooling element ( 9) The waste heat flow (26) is led out, wherein a control loop regulates the actual temperature to the setpoint temperature, and wherein means for determining the heat flow are provided, characterized in that the change of the heat flow results in a difference between the temperature setpoints. Correction. The apparatus of claim 13, wherein the heat flow used in temperature rating correction is the waste heat flow (26) or the heat power (10). A method for thermally treating at least one substrate at a controlled temperature in a process chamber of a device by means of a heating element generated from a heatable element (5) as a result of an external input of thermal power (10) The heat flow from the heated substrate holder (4) through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to the cooling element (9) cooling the top of the process chamber, the cooling element ( 9) Exporting the waste heat flow (26) to the outside, wherein the temperature control system has at least one control loop, wherein the heat flow is a control variable, characterized in that the heat flow used in the temperature control is the waste heat flow (26) or The thermal power (10). The method of claim 15, wherein, in order to control the heat flow, the thermal power (10) of the heating element (5) is varied. The method of claim 16, wherein the rating (29) of the heating device controller (11) for controlling the thermal power (10) is the surface measured on the substrate holder (4) or on the substrate (2) The temperature, in the event of a change in heat flow, is changed by the setpoint value setting device (28) to the setpoint value (29). The method of claim 17, wherein the rated value is changed when the degree of change in the integral determined by the penetration time of the deviation of the heat flow from the set standard value reaches a set amount (29). A device for thermally treating at least one substrate at a controlled temperature in a process chamber of the device by means of a heating element generated from a heatable element (5) as a result of an external input of thermal power (10) The heat flow from the heated substrate holder (4) through the substrate (2) heated by the substrate holder (4) and the process chamber (1) to the cooling element (9) cooling the top of the process chamber, the cooling element ( 9) The waste heat flow (26) is led out, wherein the temperature control system has at least one control loop, wherein the heat flow is a control variable, characterized in that the heat flow used in the temperature control is the waste heat flow (26) or The thermal power (10). The apparatus of claim 19, wherein, in order to control the heat flow, the thermal power (10) of the heating element (5) is varied. The device of claim 20, wherein the rating (29) of the heating device controller (11) for controlling the thermal power (10) is the surface measured on the substrate holder (4) or on the substrate (2) The temperature, in the event of a change in heat flow, is changed by the setpoint value setting device (28) to the setpoint value (29).

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