Method for Recording State of CVD Reactor under Processing Conditions

Abstract

The present invention relates to a method for operating a CVD reactor (1) having a process chamber (3), in which a substrate (2) is placed in the process chamber (3) during a process in one or more process steps (R1, R2, R3) of a process phase (PR), a process temperature (T) and pressure (P) are set, and a process gas flow (Q) is supplied into the process chamber (3) according to control data delivered by a control unit (10) in accordance with a formula stored in the control unit (10). During the process, sensors are used to determine measurement data, from which a current characteristic is calculated and compared with a previous "characteristic" determined in a similar manner in one or more previous processes. The present invention proposes that the "characteristic" consists solely of a value or group of values ​​obtained from measurements recorded during one or more adjustment steps (C1.1, C1.2, C1.3) of an adjustment phase (PC, PC'). In the adjusting phase (PC, PC'), the adjusting temperature (T) and adjusting pressure (P) are set respectively, and the adjusting gas flow (Q) is supplied to the process chamber (3) according to the control data delivered by the system.

Description

Technical Field

[0001] The present invention relates to a method for operating a CVD reactor having a process chamber. During a process, in one or more process steps of a process phase, a substrate is placed in the process chamber, and each of the process temperature, pressure, and process gas flow into the process chamber is supplied by a control unit according to a manner stored in a controller, set by control data, the measured values are determined by sensors during the process, and from the measurement data, a current "feature quantity" is calculated, and the "feature quantity (fingerprint Fingerabruck)" is compared with past feature quantities determined in the same manner in one or more older processes.

[0002] A CVD reactor is part of a coating apparatus, and in the manufacturing process of a coated semiconductor substrate, according to a manner determined by the operation of the apparatus, a substrate processing phase is executed, and the substrate is applied automatically, semi-automatically, or manually on a susceptor disposed in the CVD reactor. The process chamber in which the susceptor is disposed is evacuated, purged, and set to a process temperature at which a process gas is supplied to the process chamber. The processing phase of the process can include a number of process steps with different process parameters, i.e., different temperatures, total pressures, or process gas components.

[0003] The CVD reactor is adjusted before and after each processing phase that poses a problem. It is also presented such that the CVD reactor is calibrated before the processing phase. The method can thus have a calibration or adjustment phase preceding the process phase in this way. In the calibration phase, process parameters, particularly the heat input parameter and the heat dissipation parameter, are changed. These are parameters that affect the heat flow into the substrate and the heat dissipation of the substrate, respectively. When these parameters are changed, the substrate temperature changes. Thus, in the calibration step, values for various parameters can be determined, thereby enabling a predetermined substrate temperature to be reached.

[0004] In the adjustment phase, the process chamber is to be shifted to a predetermined set state. The adjustment phase also usually consists of a number of steps, i.e., a number of adjustment steps. During the adjustment step, the process chamber is heated up to the adjustment temperature. The adjustment gas is taken into the process chamber. This adjustment gas can take the form of an etching gas, such as a compound containing chlorine or halogen. However, the adjustment gas can also be other gases. The adjustment gas can be used to clean the process chamber. The adjustment gas can also be accompanied by a pre - coating or adjustment of the surface of the process chamber. At least one adjustment step is carried out along fixed - defined process parameters.

[0005] Patent Document 1 and Patent Document 2 describe an operation method of a CVD reactor. Therein, the characteristic quantities are formed from measured values determined during the process. Each individual characteristic quantity is associated with each process step. The past characteristic quantities formed in this way can be compared with the current characteristic quantities in order to obtain early information about the operation of the state of the CVD reactor.

[0006] Patent Document 3 describes an operation method of a CVD reactor. A plurality of CVD reactors of the same design are used in a factory. In order to detect whether the process data in each individual reactor is affected by drift, characteristic "characteristic quantities" are formed from the measurement data and these characteristic quantities can be compared with each other.

[0007] Patent Document 4 describes an operating method of a CVD reactor. Process data is acquired during a process step and saved as data collection.

[0008] Patent Document 5 describes a system and method for guaranteeing the quality of a CVD deposition process. Measurement values are determined during operation and compared with past measurement values. A method for determining parameters, where a number of values are determined in a calibration process preceding the processing, is a known technique according to Patent Document 6. From a number of values, parameters for realizing an actual temperature approximately close to a predetermined temperature are determined. Here, the temperature rises stepwise using a "set method". At each step, the value of the temperature is measured from a plurality of sensors. The values thus obtained form a matrix, and a temperature model calibrated using the matrix is calculated from a standard model considering heat characteristics. The calibrated temperature model reproduces the achieved actual temperature.

[0009] The above prior art documents enable processes having a series of independent process steps to be compared with each other regarding process stability. If control data is changed by a user, updated feature quantities must be acquired in order to analyze the stability of a process to be executed later using the same control data.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

[0011] An object of the present invention is to obtain reliable knowledge about the temperature characteristics related to the state of a CVD reactor apparatus even when a user changes control data during a process phase. [Means for Solving the Problems]

[0012] That object is achieved by the present invention as specified in the claims. The dependent claims not only represent advantageous developments of the subject matter described in the independent claim but also are independent means for solving the object.

[0013] According to a first aspect of the invention, a method is proposed, which enables a meaningful statistical analysis of the state of an apparatus, especially even when mutually different process steps are executed during a process phase.

[0014] First, it is proposed to execute at least one adjustment step using fixedly defined, invariant process parameters. Each of the numerous processes executed in the production of a coated semiconductor substrate has this at least one first adjustment step, which can be combined, if necessary, with a second adjustment step having specific process parameters. In the present invention, process data is determined at least during the first adjustment step, and these process data are statistically evaluated with similar process data. In this way, the process data that are statistically correlated with each other are only those determined in the same first adjustment step, that is, only those executed using the same predetermined process parameters. In particular, the process data are measurement data such as the total pressure in the process chamber, the temperature in the process chamber, or the partial pressure of the measured process gas. The process parameters are the set temperature, set pressure, and set flow of the process gas. The process parameters and process data can also be set values and measured values such as the temperature and humidity values of the temperature control tank.

[0015] The CVD reactor has a control unit. This control unit has a storage unit. The method can be stored in the storage unit. The process is executed according to the method. The process can be divided into two phases. An adjustment phase in which the process chamber is adjusted when there is no substrate or when there is a dummy substrate, and a process phase in which a process is performed on the substrate disposed in the process chamber, for example, coating one or more layers on the substrate. Both the process phase and the adjustment phase each comprise a plurality of steps. The control unit provides control data for each process step and each adjustment step, and accordingly, the adjustment temperature or process temperature, the adjustment pressure or process temperature, and the adjustment gas flow or process gas flow are set. The adjustment gas flow and the process gas flow can thereby have a number of individual gas flows, for example, a carrier gas flow and a plurality of reaction gas flows. During each individual step, the measured values are recorded by appropriate sensors at individual points both inside and outside the process chamber. The measured values can also include the partial pressure in the gas phase both inside and outside the process chamber. However, the measurement data can also include the temperature at individual positions inside or outside the process chamber. Therefore, the measurement data can also include the exhaust gas temperature or the temperature of the wall inside the process chamber. However, it is also possible to take into account the measured values obtained from exhaust gas sensors and other devices, for example, sensors that measure the temperature of pumps or cooling circuits. The measured values can be recorded in the control cabinet, in the CVD reactor in the cabinet where the gas mixing system is arranged, when mounting and removing the CVD reactor to / from the cabinet for mounting in the cabinet, or in the pump housing. In a preferred example of the present invention, the adjustment phase has a plurality of first adjustment steps. That is, the adjustment steps are always executed by the same process parameters, and the plurality of first adjustment steps are preferably directly Next It is desirable that they are. The values measured during the adjustment step are stored.

[0016] In order to calculate the past "feature quantities", the past measured values are statistically evaluated. Preferably, only such measured values obtained from a large number of past processes, such as those obtained during similar adjustment steps in all processes, are used. The past "feature quantities" can thus be the calculation results and are related to the measured values of the adjustment steps executed using the individual process parameters. The current "feature quantities" to be compared with the past "feature quantities" can be obtained by deriving the minimum value, maximum value, average value, and standard deviation using the measured values determined in one or more adjustment steps having the same process parameters, similar to those used to determine the past feature quantities. In order to identify the deviation from the set state of the CVD reactor or CVD apparatus, the past statistical data obtained by the above method is related to the current process data. In the process, the manufacturing apparatus having the CVD reactor goes through the following manufacturing cycle. For example, a predetermined algorithm, that is, a calculation rule, is used to calculate a value or a group of values referred to as "feature quantities" from the past measured values and the current measured values. From the statistical calculations, a one-dimensional or multi-dimensional window can be calculated, and the current "feature quantities" must exist in order to confirm whether the actual state of the CVD reactor is in the correct order. The process is a manufacturing cycle comprising a plurality of substantially fully automated phases, where the essential phases are the process phase and the adjustment phase.

[0017] The process usually begins with preparing a reactor loaded with a substrate to be coated. An uncoated substrate is brought into the process chamber from the outside for this purpose. The process chamber is prepared for the deposition process. Then the deposition process is as follows. The deposition process is a process phase in which a plurality of coating processes can be executed using different process parameters. The coating process has a plurality of process steps. After the deposition process is completed, the CVD reactor prepares to move the substrate out of the process chamber. After the coated substrate is moved out of the process chamber, the process chamber is prepared for an adjustment step. And a plurality of first and second adjustment steps are executed in an adjustment phase. The second adjustment phase is different from the first adjustment step in that it is executed using control parameters that can be modified or modified by the operator of the device. And the first adjustment step exclusively has control parameters that are fixedly determined and cannot be modified by the operator of the device, but can only be modified by the manufacturer of the device.

[0018] In a first variant, the first adjustment step is preferably part of each process, and is an individual element of a plurality of processes, having the same first adjustment step and capable of having different process steps or second adjustment steps from each other. On the one hand, in the adjustment step of this first variant form, a cleaning step can be included. For example, chlorine or ammonia is supplied to the process chamber. Thereby, the plastic deposited on the walls of the process chamber is removed at a high temperature. The first adjustment step of the second variant form can be a tempering step. This variant form is essentially only carried out after the maintenance of the process chamber, during which the process chamber is opened to let air into the inside of the process chamber. By baking the process chamber at a high temperature, for example, between 700 °C and 1200 °C, all the water absorbed on the surface of the inner wall of the process chamber is removed. In particular, hydrogen is supplied into the process chamber. In this type of adjustment, the adjusted process chamber temperature can be presented to rise in a plurality of steps in the range of about 700 °C to about 1200 °C.

[0019] Here, during each of these steps, it can be presented that the heat flow from the heating device for heating the susceptor to the cooling device arranged above the process chamber is changed. For this purpose, for example, the thermal resistance of the process chamber ceiling can be changed by supplying a temperature control gas with variable thermal conductivity into the gap. This gap is arranged, for example, between the lower ceiling plate and the upper ceiling plate of the process chamber ceiling, and it is desirable that this is adjacent to the temperature control mechanism. In this type of adjustment, a number of measured values are recorded, especially the process chamber ceiling temperature and the substrate temperature measured on a dummy wafer arranged on the substrate holder. This measurement can be carried out using a pyrometer. Values are obtained from these measurements, which are performed simultaneously, and these values can be compared with past values. This value can take the form of a single measurement value. However, it can also take the form of a value statistically determined from one or more, multiple measurement values. The processes described above are automated as completely as possible. The intervention of the manual operation of the device operator consists essentially of the preparation of the cassette using an uncoated substrate or the removal of the cassette using a coated substrate. The device operator also defines the processing method using set values based on process parameters, and accordingly, the installation of a control program that provides to actuators such as, for example, a mass flow controller, a heating device, or the like is accompanied.

[0020] The adjustment phase has adjustment steps such as the following, for example. (a) Heating of the process chamber under a hydrogen atmosphere, (b) Switching to an inert gas atmosphere (nitrogen), (c) Introduction of an etching gas (Ch) for cleaning the process chamber and cavities adjacent to the process chamber such as a gas inlet member and a gas discharge member, (d) Purging of the process chamber and cavities adjacent thereto using an inert gas, (e) Increase in the process chamber temperature and introduction of an adjustment gas such as NH3 for heating the process chamber and cavities adjacent thereto, (f) Purging of the process chamber using an inert gas and NH3 as required, (g) Introduction of an etching gas such as chlorine for cleaning the process chamber and cavities adjacent thereto (this step can be repeated multiple times as required), (h) Purging of the process chamber and cavities adjacent thereto using an inert gas, (i) Increase in the process chamber temperature, introduction of other adjustment gases or NH3 again, and switching to a hydrogen atmosphere for heating all parts of the CVD reactor that come into contact with the process gas or adjustment gas, (j) Cooling of the reactor under a hydrogen / ammonia atmosphere, (k) Purging the interior of the reactor using an inert gas.

[0021] Essentially with respect to the cleaning steps (g), (j), (k), the operator of the device can obtain free parameters.

[0022] Throughout the adjustment phase, data such as the cooling bath temperature or the control cabinet exhaust characteristics are recorded, and the data is not modified during individual adjustment steps. These values are used to evaluate the stability and validity of the measured values, especially other values. The temperature sensor is used to record the heat flow among other information. For this purpose, data from temperature sensors, especially pyrometers, is used. Using the temperature sensor, it is possible to evaluate the state of the heating device or other components of the reactor that can control the temperature. In particular, data from the region of the vacuum system is also recorded, and that system includes especially the throttle valve and the pump.

[0023] A second aspect of the present invention relates to a method for determining parameters for controlling the temperature of the surface of a substrate supported by a susceptor of a CVD reactor at a predetermined substrate temperature for heat-treating the substrate at said temperature in at least one process step of a process phase. The first parameter is a heat input parameter that affects the first heat flow supplied from the heat source to the susceptor, and the second parameter is a heat dissipation parameter that affects the second heat flow disappearing from the surface of the substrate to the heat sink.

[0024] A general CVD reactor has a substrate disposed in a heat transfer path that is typically between a heat source, which is a heating device for heating the susceptor, and a heat sink, which is typically a process chamber ceiling or a cooling device adjacent thereto. The temperature of the surface of the substrate supported by the susceptor depends on the heat input parameter. The thermodynamic relationships are described in particular in Patent Document 7, and the heat transfer paths between the heat source and the substrate and between the substrate and the heat sink are considered as heat flow resistances. These heat flow resistances can be modified depending on changes in properties such as the surface properties in the process chamber, especially in the use of the process chamber. In particular, the heat flow resistance depends on the nature of the process steps previously carried out in the process chamber. In particular, they are affected by the surface of the susceptor and the plastic occupancy of the process chamber ceiling. The heat input parameters include, for example, the susceptor temperature measured especially on the lower surface of the susceptor, that is, the surface facing the heating device, and the lower surface of the susceptor is adjusted to that temperature. However, the heat input parameters can also include the power supplied to the heating device. The heat dissipation parameters can also include the temperature of the process chamber ceiling. It can also be adjusted to the set temperature. This can be done by modifying the cooling performance of the cooling device. However, it is also possible to affect the process chamber ceiling temperature by changing the mixing ratio of the temperature control gas supplied to the gap between the process chamber ceiling and the cooling device. This temperature control gas is composed of two gases having different thermal conductivities.

[0025] The object of the present invention is to embody a reliable method for determining the values of the heat input parameters and the heat dissipation parameters, at which values a predetermined substrate temperature is determined on the surface of the substrate facing the process chamber.

[0026] The object is achieved by determining a number of tuple values in one or more calibration steps. Each said tuple value has a value of a first parameter and a value of a second parameter. These parameters can include the adjusted susceptor temperature and / or the adjusted process chamber ceiling temperature. However, the parameters can also include the heating power and / or the mixing ratio of the temperature control gas or the heat dissipation capacity of the cooling device. A function representing the actual temperature of the surface of a substrate by at least one parameter is defined from a number of tuple values by at least one-dimensional interpolation. This function may include individual functions of a function set. From this function, which can also be a two-dimensional function, at least one parameter is obtained, correlated with the actual temperature of the substrate surface, and the temperature is closest to a predetermined substrate temperature from the method. For this purpose, a so-called inverse function is derived, especially from a one-dimensional function. The above method can be used for the determination of tuple values. In this method, a first parameter, such as susceptor temperature, for example, is modified, especially increased step by step. During each step, a second parameter, such as process chamber ceiling temperature, for example, is also changed, that is, increased step by step. This is carried out in the above method by supplying temperature control gases of different configurations to the gap between the process chamber ceiling and the cooling device. The number of measured values obtained by this method may include grid points of a two-dimensional mathematical function that can be represented as a surface. This function can be represented in a three-dimensional coordinate system. For example, the X-axis represents the susceptor temperature, the Y-axis represents the process chamber ceiling temperature, and the Z-axis represents the measured surface temperature of the substrate. The susceptor temperature and the process chamber ceiling temperature can be adjusted temperatures. The actually measured substrate surface temperature can be measured by a pyrometer. A function configured in such a grid can be interpolated like the surface on a hill. From the resulting surface, a point on the X-Y surface that gives a function value closest to a predetermined substrate temperature can be identified. However, in an alternative equation for the measured values obtained, a plurality of one-dimensional functions are used, and each calibration step performed at the same susceptor temperature provides an interpolated measurement curve showing the measured substrate surface temperature with respect to the process chamber ceiling temperature. A so-called inverse function is derived from this measurement curve, and the process chamber ceiling temperature, which correlates with the substrate surface temperature closest to the predetermined substrate temperature at the parameter, that is, the susceptor temperature in question, can be determined. In the process phase following the calibration phase, the calibration curve obtained in the calibration phase is used instead of the standard calibration curve to correct parameters such as a predetermined susceptor temperature or a process chamber ceiling temperature by a method. In a predetermined method, parameters such as a susceptor temperature and a process chamber ceiling temperature are determined. Accordingly, a required substrate temperature is obtained according to a standard characteristic curve. In the calibration phase, a corrected characteristic curve is obtained, and a corrected set value is obtained based on the corrected characteristic curve.

[0027] The device according to the present invention has a control unit and is programmable. By programming, process parameters in the adjustment phase and the process phase can be determined. According to an advantageous design of the present invention, each process, and particularly each process executed using the device, includes one or more calibration or adjustment steps and is executed using fixed predetermined process parameters. These calibration or adjustment steps cannot be omitted by the user. Also, the process parameters of these calibration or adjustment steps cannot be modified. According to an advantageous design of the present invention, only the measured values obtained in these invariant steps using invariant process parameters are used to form "feature quantities". The feature quantities are determined in this way in the steps of a process defined in an invariant manner using fixed predetermined process parameters such as, among others, the total pressure in the process chamber, the gas flow through the process chamber, and at least one or a plurality of fixed temperatures in the process chamber. This is advantageous in that the operating state of the device can be objectively specified even when different manufacturing processes using the device are executed.

Brief Description of the Drawings

[0028] The present invention will be described in more detail below based on exemplary embodiments.

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Figure 11

Embodiments for Carrying Out the Invention

[0029] Figure 1 shows an overview of a CVD reactor. It is a part of the device according to the present invention, on which the method according to the present invention can be implemented.

[0030] The process chamber 3 is arranged inside the externally airtight housing of the CVD reactor 1, and in particular, this CVD reactor 1 is made of stainless steel. The process chamber is arranged above a susceptor 4 made of graphite or coated graphite. The susceptor 4 can be heated from below using an infrared heating device 6. The alternating electromagnetic field generated by the heating device 6 generates eddy currents in the susceptor 4, resulting in the heating of the susceptor 4. One or more substrates 2 are placed on the upper surface of the susceptor 4, and the substrates 2 will be coated during the process executed in the process chamber 3. A carrier gas or a process gas can be supplied into the process chamber 3 through the gas inlet 5. A vacuum pump 12 is provided, and a throttle valve 11 is arranged in front of it. The control unit 10 is used to adjust the gas flow of the gas sources indicated by 7, 8, and 9. The gas sources 7, 8, 9 are supplied to the process chamber 3 through the gas inlet 5. The control unit 10 can also be used to control the heating device 6, the throttle valve 11, and the pump 12.

[0031] For example, a liquid source 13 containing an organometallic compound is arranged in a temperature control tank 14, and the temperature of the temperature control tank 14 can be monitored. The process chamber ceiling 18 has a cooling device (not shown) and means for influencing the thermal conductivity of the process chamber ceiling 18. The entire device is arranged in a cabinet 15 and can be essentially sealed airtight from the surrounding environment. The cabinet 15 has an air supply 16 and an exhaust 17. The gas components and the exhaust temperature in the exhaust 17 can be measured.

[0032] The cooling flow can pass through the cavity of the helical heating device 6. Its temperature is monitored by a sensor.

[0033] Mutually different methods can be stored in the control unit 10, and these are used to deposit various layers on the substrate 2.

[0034] In each case, the process comprises a number of steps, which can be divided into mutually different phases. For example, in the adjustment phase PC which is carried out before the actual coating phase, the process chamber 3, i.e. the reactor system, is brought to a set state. The adjustment steps C1.1, C1.2, C1.3 are executed using mutually different adjustment parameters. In the different adjustment steps C1.1, C1.2, C1.3, for example, the temperature T in the process chamber 3, or the total pressure P in the process chamber 3, or the gas flow Q (quantity and / or quality) of the adjustment gas can be different. However, in any process carried out using a CVD reactor, the control parameter SP embodied for the control of the temperature, total pressure, or gas flow is fixed and cannot be modified by the user.

[0035] In the exemplary embodiment shown in FIG. 2, the adjustment phase has three adjustment steps, each of which must be executed using invariant control parameters.

[0036] In the exemplary embodiment shown in FIG. 3, the adjustment phase PC has, in addition to the first adjustment steps C1.1, C1.2, C1.3 which must be executed using fixed predetermined control parameters, second adjustment steps C2.1, C2.2 which can be executed using variable control parameters. In the adjustment steps C2.1, C2.2, the user can modify the control parameters.

[0037] The adjustment phase PC is followed by the process phase PR. There, it has various successive process steps R1, R2, R3 which perform a process such as coating the substrate 2 with one or more layers on the substrate disposed in the process chamber 3. The control parameters of the process steps R1, R2, R3 can be changed by the user.

[0038] According to the present invention, the measured values are collected during all steps of the adjustment phase PC and the process phase PR, which are determined using sensors for measurement. This measurement data is stored in the storage unit or storage system of the control unit 10.

[0039] According to the present invention, the "characteristic quantity" is formed only from the measured values obtained during the invariant first adjustment steps C1.1, C1.2, C1.3. For this purpose, the measured values are associated with each other in an appropriate manner such that at least one value forming the "characteristic quantity", or a group of values forming the "characteristic quantity", is generated. For example, the minimum value, the maximum value, and the standard deviation can be derived. This is done, inter alia, by using measured values from a large number of processes considered normal and carried out in the past.

[0040] Broadly speaking, the characteristic quantity can be a specific value. However, it is preferable that the "characteristic quantity" is composed of a number of values obtained from a number of measured values. The measured values can include, for example, the coolant temperature, the exhaust temperature, the temperature of the temperature control tank 14, the pump temperature, the ratio of the gas flow, and the pressure. From these measured values, a measurement series can be formed during the adjustment step. Statistical values are derived from these measurement series, such as the minimum value, the maximum value, the average, and the standard deviation. The statistical values can be part of the characteristic quantity.

[0041] The "characteristic quantity" of the current process determined by the same rule can be compared with the past "characteristic quantity" formed from the evaluation of a number of past processes. Here, for example, it can be checked whether the current "characteristic quantity", i.e., the value embodying the "characteristic quantity", is within the window of the tolerance value.

[0042] The measured values used to form the current or past "characteristic quantity" can take the form of measured values measured within the process chamber 3, such as the walls, ceiling, or other areas of the process chamber 3. However, they can also take the form of measured values determined outside the process chamber, for example, in the exhaust gas flow. Here, the exhaust gas temperature or gas concentration of the exhaust gas can be measured. Furthermore, it is presented that the pump temperature, valve position, or actual gas flow can be used as measured values that form "characteristic quantities". For example, the temperature of the coolant flowing through the heating coil 6 is also used as a measured value.

[0043] Some of the gas sources 7, 8, 9 can be arranged in a temperature control tank. The temperature of these temperature control tanks can be used as a measured value for forming "characteristic quantities".

[0044] The device can have a control cabinet. For example, it is a cabinet in which electrical components are arranged, or a cabinet in which a mounting or removal device for a gas mixing system or a CVD reactor is arranged. In the latter case, a sensor for measuring the temperature of the characteristic control cabinet can be provided. This temperature can be used in the determination of "characteristic quantities".

[0045] The system can include a cooling water circuit, and it is used to cool, for example, the process chamber ceiling or the reactor housing 1. The temperature of the cooling water can also be used in the "characteristic quantity" method.

[0046] What is important is that the parameters of the adjustment steps used for past "characteristic quantities" are the same as the parameters of the adjustment steps in which the current "characteristic quantity" is determined, and the current "characteristic quantity" is determined from the measured values of those parameters.

[0047] Using the above method, the current "characteristic quantity" can be evaluated according to a predetermined statistical rule. In particular, it can be checked whether it is necessary to provide information to the user so that the current "characteristic quantity" can plan maintenance and measurement. The comparison of the current "characteristic quantity" with the past "characteristic quantity" is thus performed by a rule-based decision system. Depending on the rule, only the data recorded in the latest event or the data from the adjustment phases in the distant past are also taken into account in the evaluation.

[0048] In the formation of "feature quantities" and the comparison of past "feature quantities" with current "feature quantities", the rules used can include the following. - Checking the value ranges of single variables and multiple variables, and limit values: For example, the average value x outside the interval [y, z], standard deviation a > b, the average value a inside the interval [b, c], and the average value x outside the interval [y, z], - Checking for changes from previous adjustment processes: For example, average value [n] < average value [n - 1] * 0.9 - Checking the value range based on a sliding window (with variable window width) over a previous adjustment process: For example, standard deviation [n] outside the interval (standard deviation [n - 1.. n - 10] - 0.5; standard deviation [n - 1.. n - 10] + 0.5) - Checking the range and limit values of inserted values based on past data

[0049] In the case of past statistical data recorded before and after maintenance or measurement, differences may be discovered as a result of rule violations or potential error warnings.

[0050] To prevent this, when considering past data (e.g., moving average), the rules can be defined such that only the data executed after the time point of the latest maintenance event is considered.

[0051] The system that executes the rules receives information regarding when a maintenance event was executed from a higher-level manufacturing control system.

[0052] As described above, a typical manufacturing cycle has alternative process phases and adjustment phases. In a first modification of the present invention, a large number of values are obtained in the adjustment steps of the adjustment phase, for example, recorded by continuous measurements during the adjustment steps. For example, temperature, flow, and pressure can be measured over a longer period of time in at least one first adjustment step. In order to form characteristic "feature quantities" from these measurement values, the temperature average value, standard deviation, minimum value, and maximum value are calculated from these measurement values. These statistical data form feature quantities, whereby the feature quantities can have a number of statistical data from various measurement values. By comparing past feature quantities with these feature quantities, the current state of the coated device can be characterized. Here, the past data is presented as being composed only of data obtained from, for example, the latest 10 adjustment phases in the past.

[0053] The process chamber is presented as being opened for the replacement of replacement parts or for other reasons and in any event for maintenance purposes. When the process chamber is thus opened, ambient air can enter the process chamber, whereby the moisture contained in the air can be absorbed onto the walls of the process chamber. In order to adjust the process chamber after a maintenance event, the process chamber is heated to a high temperature while in a near-vacuum state or while hydrogen is being supplied to the process chamber. The hydrogen is discharged again using a pumping device. Such a temperature is in the range of 700 °C to 800 °C. This heating is carried out in a plurality of steps. This heating is given to the control unit 10 and is carried out in accordance with process parameters that cannot be modified, especially by the system operator.

[0054] However, instead of an adjustment phase, a calibration phase can also be carried out before the process phase. In particular, however, both the calibration phase and the adjustment phase are presented as being carried out before the process phase. In the calibration phase, a plurality of tuple values are determined by changing the susceptor temperature TS and the process chamber ceiling temperature TC in one or more calibration steps. Each tuple value has measured values of the susceptor temperature TS, the process chamber ceiling temperature TC, and the surface temperature TW of the substrate 2.

[0055] FIG. 6 shows a schematic cross-sectional view through the CVD reactor. Therein, the heating device 6 generates a heat flow H1 into the susceptor 4. The substrate holder 19 is disposed in a pocket of the susceptor. This holder is supported by a gas cushion, which is generated by a purge gas flow QS. In this way, a gap 21 is formed between the bottom of the pocket of the susceptor 4 and the lower surface of the substrate holder 19. A second heat flow H2 flows through the gap 21. This heat passes through the substrate holder 19 and through the susceptor 2 placed on the substrate holder 19. The heat flow indicated as H3 is from the surface of the substrate 2 towards the process chamber ceiling 18. This process chamber ceiling 18 is located away from the cooling device 22 by a gap 20. The temperature control gas is located in this gap 20. The temperature control gas is formed from the purge gas QC supplied to the gap 20, and the purge gas QC is a mixture of gases having different thermal conductivities from each other. For example, H2 and N2. The heat flow H4 through the gap 20 can be affected by a change in the composition of the purge gas QC.

[0056] Above the process chamber ceiling 18, a cooling device 22 is disposed and is lowered to a set temperature by a coolant. The temperature of the coolant can be measured and is also used in the formation of the characteristic quantity.

[0057] By the balance of the thermal conductivities of all the heat flows H1, H2, H3, H4, the surface temperature of the susceptor 2, that is, the substrate temperature TW, and the temperature of the process chamber ceiling, that is, the process chamber ceiling temperature TC, can be affected.

[0058] The first temperature regulating device indicated by reference numeral 23 has a set value T SoThe susceptor temperature Ts measured on the lower surface of the susceptor 4 is adjusted. This is done by affecting the heating power LS supplied to the heating device 6. The susceptor temperature Ts or the heating power LS forms a heat input parameter, whereby the heat fluxes H1, H2, H3 from the heating device 6 to the substrate 2 are affected.

[0059] The second control loop indicated by reference numeral 24 thereby adjusts the setpoint T Co with respect to which the process chamber ceiling temperature TC is adjusted. This can be done by affecting the coolant temperature of the cooling device 22. However, this can also be done by changing the mixing ratio of the temperature control gas QC supplied to the gap 20. The temperature control gas is composed of a mixture of a gas with high thermal conductivity such as H2 and a gas with low thermal conductivity such as N2. The process chamber ceiling temperature TC, or the mixing ratio of the temperature control gas QC, or the cooling capacity of the cooling device 22 forms a heat dissipation parameter.

[0060] FIG. 7 is a temperature-time chart. FIG. 7 shows that four first calibration or adjustment steps C1.1, C1.2, C1.3, C1.4 are executed continuously. During these calibration or adjustment steps C1.1, C1.2, C1.3, C1.4, the susceptor temperature Ts measured on the lower surface of the susceptor rises stepwise from about 750° C. to about 1200° C. The substrate temperature Tw and the process chamber ceiling temperature TC are measured in parallel.

[0061] The measured values N1, N2, N3, N4, N5, N6, N7, N8, N9, N10, N11, N12, N13, N14, N15, N16 of the substrate temperature Tw are found to be lower than the susceptor temperature Ts. The susceptor temperature Ts is used to adjust the process temperature.

[0062] The lower curve in Figure 7 shows information on the process chamber temperature TC. In each of the four calibration or adjustment steps, the mixing ratio of the purge gas QC supplied to the gap 20 is continuously changed over time. Measurement M1 is a temperature measurement of the process chamber ceiling temperature. The H2 content in the H2 / N2 mixture of the purge gas QC is 95%. Measurement M2 is obtained at a mixing ratio of 35%, measurement M3 at a mixing ratio of 65%, and measurement M4 at a mixing ratio of 5%. A total of 16 temperature values TC were obtained, and 16 temperature values TW could be obtained during the four calibration or adjustment steps. In each of the calibration or adjustment steps, the four purge gas components shown above are continuously supplied to the gap 20 of the process chamber ceiling 18. Each of the measurements M1 - M16 and N1 - N16 is taken over a certain number of seconds, for example, 20 seconds. During the measurement, the average value and other statistical data are obtained. The measured values N1 - N16, M1 - M16, and in addition, the calculated statistical data represent the "temperature characteristics" of the CVD reactor.

[0063] In addition, the time gradient, that is, the first derivative with respect to time, can also be calculated from the individual measurements obtained in the sequence of measurements in the problem. These are statistically evaluated in the method described above. The statistical data can also be calculated from the values obtained above. These are included in the temperature characteristics. The temperature characteristics thus obtained can be compared with one or more past characteristics or the average of past characteristics. Figure 8 shows pairs of measured values representing the measurements N1 / M1, N2 / M2... N16 / M16 by K1, K2, K3, K4 to K16. The process chamber ceiling temperature TC for each measurement M1, M2... is shown on the X-axis. The measured substrate temperature TW is plotted on the Y-axis. It is the measured values N1, N2... that determine the positions of the points K1, K2... in this way. The solid line is a regression curve and can be compared with the dotted line representing past characteristics.

[0064] Figure 9 attempts to provide a presentation similar to that of Figure 8. However, here, instead of a linear regression curve, a quadratic regression curve is drawn passing through points K1, K2, K3, and K4. The points K1, K2, K3, and K4 on this curve can be compared with the past measurement points K’1, K’2, K’3, and K’4, where the separation d1 there is determined for the susceptor temperature TW, and the separation d2 is determined for the process chamber ceiling temperature TC. These separations d1 and d2 are compared with a maximum value. If the separations d1 and d2 exceed a specific maximum value, it indicates that something has changed in the state of the CVD reactor. However, if the separations d1 and d2 are within a window of a predetermined value, it is understood to mean that the CVD reactor is in a set state.

[0065] This method shown in Figure 7 is also used to determine the temperature characteristics of the CVD reactor 1 and, in particular, to construct the characteristic curve. In one or more process steps, parameters are determined in a calibration phase that is executed before the substrate 2 undergoes a heat treatment, especially the process phase where it is coated, and using these, a predetermined substrate temperature TW can be set. These steps represented by C1.1, C1.2, C1.3, and C1.4 in Figure 7 form the calibration steps. In the calibration steps, the mixing ratio of the temperature control gas QC is adjusted to each fixed value of the susceptor temperature TS. This mixing ratio and the cooling capacity of the cooling device 22 form further parameters. This is repeated for a number of different susceptor temperatures TS. In each case, the measured values determined by this method form a tuple. The tuple includes the following elements. The set and, in particular, the adjusted susceptor temperature TS, the mixing ratio of the temperature control gas, or the adjusted temperature TC of the process chamber ceiling, and, if necessary, not only the cooling capacity of the cooling device 22 but also, if necessary, the heat input parameters or heat dissipation parameters that affect the heat flow to the susceptor 2 and the heat dissipation from the substrate.

[0066] For simplicity, FIG. 10 shows the influence on the substrate temperature TW of only two parameters, namely the susceptor temperature TS and the process chamber ceiling temperature TC. The substrate temperature TW is shown as a two-dimensional function F that includes two independent variables TC and TS. The function F is calculated by (two-dimensional) in-plane interpolation on grid points formed by the measured tuple values. From the "hilly surface" obtained in this way, the value TW1 that is closest to a predetermined substrate temperature is identified, i.e., the point that coincides with the predetermined substrate temperature is identified. The value TW1 coincides with the value TC1 of the process chamber temperature and the value TS1 of the susceptor temperature TS.

[0067] In the process step of the process phase executed after the calibration phase, the substrate temperature TW reaches the value TW1, the susceptor 4 is adjusted to the susceptor temperature TS1, and the process chamber 18 is adjusted to the temperature TC1.

[0068] FIG. 11 shows the standard characteristic curve 25 defined by the method. The point 26 is the point at which, under standard conditions, at a predetermined susceptor temperature TS, the process chamber ceiling temperature TC1 leads to the substrate temperature TW1. The standard characteristic curve 25 is one curve of a set of curves, and each curve of the set of curves coincides with a different susceptor temperature TS.

[0069] The reference numeral 25' indicates a modified characteristic curve. This modified characteristic curve 25' is determined by the calibration method described above. This modified characteristic curve 25' is also one curve of a set of curves. The set of curves has a number of curves, and each curve is recorded at one of the different susceptor temperatures TS, namely in each of the calibration steps C1.1, C1.2, C1.3, C1.4. From the measured values recorded in the individual calibration steps C1.1, C1.2, C1.3, C1.4, the curve of the function F representing the modified characteristic curve 25' is identified by interpolation. The inverse function can be derived from this function F. Thereby, the current process chamber ceiling temperature TC2 can be directly determined for a predetermined substrate temperature TW1.

[0070] By selectively changing parameters that affect the heat flow to and heat dissipation from the substrate, it is a considered advantage, among other factors, that tuple values are determined during the calibration phase. The parameters are, for example, the susceptor temperature TS and / or the process chamber ceiling temperature TC. The tuple values include the respective measured substrate temperature as a further factor. Using interpolation, a set of multidimensional or one-dimensional functions is determined from these tuple values. Based on these functions or the set of functions, by means of interval reduction methods, Taylor expansion, or other suitable mathematical methods, especially numerical methods, a parameter set is determined to match the substrate temperature TW that is closest to or matches the desired substrate temperature in the process step.

[0071] It is a particularly advantageous consideration if the calibration step carried out to identify the calibration function F is part of the adjustment phase.

[0072] The above description is for explaining the invention encompassed by the present application as a whole, and independently advances the prior art by at least the following combination of features, and two, a plurality, or all of these combinations of features can also be combined.

[0073] A method characterized in that the "feature quantity" is composed of or only from a value or a group of values obtained from measured values, the measured values being recorded during one or more calibration or adjustment steps C1.1, C1.2, C1.3 of the calibration or adjustment phase PC, PC', in which at least the calibration or adjustment temperature T and the calibration or adjustment pressure P are respectively set, and the calibration or adjustment gas flow Q is supplied to the process chamber 3 according to the control data provided by the method.

[0074] The "feature quantity" is One or more Calibration or adjustment phase Z PValues obtained from the measured values recorded during one or more calibration or adjustment steps C1.1, C1.2, C1.3 of C and PC’, or consisting only of a group of values, or consisting only thereof, in the calibration or adjustment phases PC, PC’, at least the calibration or adjustment temperature T and the calibration or adjustment pressure P are respectively set, and the calibration or adjustment gas flow Q is supplied to the process chamber 3 according to the control data provided by the method, characterized device.

[0075] The calibration or adjustment step has a first calibration or adjustment step C1.1, C1.2, C1.3 and a second calibration or adjustment step C2.1, C2.2, and the “characteristic quantity” consists only of values or a group of values obtained from the measured values recorded during the first calibration or adjustment step C1.1, C1.2, C1.3, and the control data of the first calibration or adjustment step C1.1, C1.2, C1.3 are stored in the control unit 10 in an invariable manner, characterized method or device.

[0076] The measured value is a value of a physical quantity measured inside or outside the process chamber, in particular the temperature of the control water, the temperature of the temperature control tank 14 of the temperature control tank, the flow rate, the temperature of the pump, the temperature or gas concentration value in the gas line or liquid line, the exhaust gas flow, or the exhaust 17 of the control cabinet or the like, characterized method or device.

[0077] At least one of the one or more first calibration or adjustment steps C1, C2, C3, C4 is a cleaning step, and the cleaning gas contains in particular a halogen such as chlorine or a hydride such as ammonia, and it is supplied into the process chamber, characterized method or device.

[0078] In particular, the “characteristic quantity” obtained by the statistical evaluation of the measured values of older processes, in particular the past “characteristic quantity”, and the statistical mean value, minimum value, maximum value, and / or standard deviation are determined, characterized method or device.

[0079] At least one of the one or more first adjustment steps C1.1, C1.2, C1.3 is a temperature control step, in which a temperature control gas, such as hydrogen, for example, is supplied to the process chamber at an elevated temperature, in particular in the range from 700 °C to 1200 °C. A method or apparatus characterized thereby.

[0080] An adjustment phase PC is executed before and after each process phase PR, during which a "characteristic quantity" is obtained. A method or device characterized thereby.

[0081] An adjustment step PC having one or more first adjustment steps C1.1, C1.2, C1.3 is executed after a preceding maintenance event W, and / or a calibration or adjustment step having one or more first calibration or adjustment steps C1.1, C1.2, C1.3 is executed after a preceding maintenance event W. Ambient air enters the process chamber 3 during the maintenance event, and the "characteristic quantity" obtained from one or more measured values is a "temperature characteristic quantity". A method or apparatus characterized thereby.

[0082] A method or apparatus characterized in that the comparison between the current "characteristic quantity" and the past "characteristic quantity" is performed according to a rule-based decision system.

[0083] A method or apparatus characterized in that the value of at least one "characteristic quantity" is calculated from a series of measured values obtained continuously over time, and in particular the differential coefficient with respect to time is formed from the measured values.

[0084] In a calibration phase that temporally precedes the process phase, in a plurality of calibration steps C1.1, C1.2, C1.3, a large number of tuple values are determined, each having values of first parameters TS, LS that cause these values, values of second parameters TS, QC, and the actual temperature TW of the substrate surface. From the large number of tuple values, a function F representing the actual temperature is formed by interpolation with at least one parameter, and from this function, values TW1 of at least one parameter TC, QC; TS, LS are obtained, which correlates with the actual temperature TW of the substrate surface that is closest to a predetermined substrate temperature.

[0085] The heat input parameter is the susceptor set temperature T So and, in response to this, the first control loop 23 adjusts by changing the heating power LS supplied to the heating device 6 or the heating power LS, and / or the heat dissipation parameter is the set temperature of the cooling device 22, the mixing ratio of the temperature control gas composed of two gases having different thermal conductivities supplied to the gap 20 between the cooling device 22 and the process chamber ceiling 18, or the set temperature T of the process chamber ceiling S and, in response to this, the second control loop 24 adjusts the actual temperature T of the process chamber ceiling So C A method characterized by that.

[0086] A method characterized in that a one-dimensional or multi-dimensional function is formed to perform interpolation, and its grid points form tuple values.

[0087] Continued A plurality of first calibration or adjustment steps are directly related to each other In particular, a plurality of calibration or adjustment steps are executed in a stepwise temperature increase or decrease in a stepwise manner and / or present changing the cooling parameter. A method characterized by that.

[0088] ​The measured values include the substrate temperature TW and the process chamber ceiling temperature TC, and in the calibration or adjustment phase PC, the temperature TS and heat conduction are continuously corrected in the heat flows H1, H2, H3, H4 from the heating device 6 to the cooling device 22. A method characterized by this.

[0089] All the disclosed features are essential to the present invention (for themselves and in combination with each other). The disclosure of the application here includes the disclosure content of the relevant / added priority documents (copies of previous applications) in their entirety, which is also for the purpose of incorporating the features of these documents into the claims of the present application. Dependent claims, especially for the purpose of filing a divisional application based on these claims, are characterized by further independent inventive developments of the prior art even without the features of the cited claims. The invention specified in each claim can additionally have one or more functions specified in the foregoing description, especially those provided with reference signs and / or specified in the description of the signs. The present invention also relates, in particular, to embodiments in which the individual ones of the features described in the foregoing description are not implemented as long as they are clearly unnecessary for their respective purposes of use or can be replaced by other means having the same technical effect.

Explanation of Signs

[0090] 1 CVD reactor 2 Substrate 3 Process chamber 4 Susceptor 5 Gas inlet 6 Heating device 7 Gas source 8 Gas source 9 Gas source 10 Control unit 11 Throttle valve 12 Vacuum pump 13 Liquid source 14 Temperature control tank 15 Cabinet 16 Air supply 17 Exhaust 18 Process chamber ceiling 19 Substrate holder 20 Gap 21 Gap 22 Cooling device 23 First control loop 24 Second control loop 25 Standard characteristic curve 25’ Modified characteristic curve 26 Point 26’ Point d1 Separation d2 Separation t Time C1.1 First calibration / adjustment step C1.2 First calibration / adjustment step C1.3 First calibration / adjustment step C2.1 Second calibration / adjustment step C2.2 Second calibration / adjustment step F Function H1 Heat flow H2 Heat flow H3 Heat flow H4 Heat flow K1..K16 Measurement values K1’..K16’ Past measurement values LS Heating force M1..M16 Measurement values N1..N16 Measurement values P Pressure P1 First parameter P2 Second parameter PC Regulation phase PC’ Regulation phase PR Process phase Q Process gas flow QC Purge gas QS Purge gas R1 Process step R2 Process step R3 Process step TS Susceptor temperature TC Ceiling temperature TW Substrate temperature

Claims

1. A method of operating a CVD reactor (1) having said process chamber (3), in which a substrate (2) is placed in the process chamber (3) during the process, wherein the process comprises a process phase (PR), and in one or more process steps (R1, R2, R3) in said process phase (PR), at least one process temperature (T), one process pressure (P), and a process gas flow (Q) are respectively set, and process gas is supplied to said process chamber (3) according to first control data that can be changed by a user based on the setting, before and after said process phase (PR), the process has a calibration or adjustment phase (PC, PC'), and in one or more calibration or adjustment steps (C1.1, C1.2, C1.3) in said calibration or adjustment phase (PC, PC'), at least one calibration or adjustment temperature (T), one calibration or adjustment pressure (P), and a calibration or adjustment gas flow (Q) are respectively set, and calibration or adjustment gas is supplied to said process chamber (3) according to second control data that cannot be changed by a user based on the setting, and, during said calibration or adjustment phase (PC, PC'), measurement data is measured by a sensor, and a current "feature quantity" is calculated by a statistical evaluation that calculates the average value, minimum value, maximum value, and / or standard deviation of said measurement data, and it is compared with past "feature quantities" calculated by the same method in one or more older processes, and, said measurement data is the temperature of cooling water, the temperature of the temperature control tank of the temperature control tank (14), the flow rate or temperature of a pump or gas line or liquid line, or the temperature or gas concentration value measured in the exhaust gas flow or the exhaust (17) of the control cabinet, a method of operating a CVD reactor, characterized by this.

2. said calibration or adjustment step has a first calibration or adjustment step (C1.1, C1.2, C1.3) and a second calibration or adjustment step (C2.1, C2.2), said "feature quantity" is, composed only of values or groups of values calculated from said measurement data recorded during said first calibration or adjustment step (C1.1, C1.2, C1.3), The method according to claim 1, characterized in that the second control data of the first calibration or adjustment step (C1.1, C1.2, C1.3) are stored in the control unit (10) in a certain manner.

3. At least one of the one or more first calibration or adjustment steps (C1.1, C1.2, C1.3) is a purge step in which a purge gas is supplied to the process chamber (3). And / or the purge gas contains halogen, or chlorine, or hydride, or ammonia, The method according to claim 1 or 2.

4. At least one of the one or more first calibration or adjustment steps (C1.1, C1.2, C1.3) is a temperature control step, in which a temperature control gas or hydrogen is supplied to the process chamber (3) at an elevated temperature and / or in a temperature range of 700 °C to 1200 °C. The method according to any one of claims 1 to 3.

5. The calibration or adjustment phase (PC) is performed before and after each of the process faces (PR), and a "feature quantity" is obtained during that time. And / or the calibration or adjustment phase (PC) comprising one or more of the first calibration or adjustment steps (C1.1, C1.2, C1.3) is performed after a preceding maintenance event (W), during which ambient air enters the process chamber (3), and the "feature quantity" obtained from one or more of the measurement data therein is a "temperature feature quantity". The method according to any one of claims 1 to 4.

6. The comparison between the current "feature quantity" and the past "feature quantity" is performed according to a rule-based decision system. The method according to any one of claims 1 to 5.

7. The value of at least one "feature quantity" is calculated from a series of the measurement data obtained continuously over time. And / or a differential coefficient with respect to time is derived from the measurement data. The method according to any one of claims 1 to 6.

8. An apparatus having a CVD reactor (1) and the control unit (10) for controlling the control unit (10). The method is stored in the control unit (10), and according to the method, during the process, the substrate (2) is placed in the process chamber (3). The process comprises a process phase (PR), and in one or more process steps (R1, R2, R3) in the process phase (PR), at least one process temperature (T), one process pressure (P), and a process gas flow (Q) are respectively set, and process gas is supplied to the process chamber (3) according to first control data that can be changed by a user based on the setting. Before and after the process phase (PR), the process has a calibration or adjustment phase (PC, PC’), and in one or more calibration or adjustment steps (C1.1, C1.2, C1.3) in the calibration or adjustment phase (PC, PC’), at least one calibration or adjustment temperature (T), one calibration or adjustment pressure (P), and a calibration or adjustment gas flow (Q) are set, and calibration or adjustment gas is supplied to the process chamber (3) according to second control data that cannot be changed by a user based on the setting, and during the calibration or adjustment phase (PC, PC’), measurement data is measured by a sensor, and a current "feature quantity" is calculated by a statistical evaluation that calculates the average value, minimum value, maximum value, and / or standard deviation of the measurement data, and it is compared with a past "feature quantity" calculated by a similar method in one or more older processes, and the measurement data is a temperature of cooling water, a temperature of a temperature control tank (14) of the temperature control tank, a flow rate or temperature of a pump or a gas line or a liquid line, or a temperature or gas concentration value measured in an exhaust gas flow or an exhaust (17) of a control cabinet, characterized by the device.

9. In at least one process step (R1) of a process phase, at a temperature (TS), for heat-treating a substrate (2) at a predetermined substrate temperature (TW), a method for determining parameters for temperature control of the surface of the substrate (2) supported by a susceptor (4) of a CVD reactor (1). The first parameters (TS, LS), which affect the first heat fluxes (H1, H2) supplied from the heat source (6) towards the susceptor (4), are heat input parameters, and the second parameters (TS, QC), which affect the second heat fluxes (H3, H4) diverging from the surface of the substrate (2) towards the heat sink (22), are heat dissipation parameters, in the determination method, In a calibration phase preceding the process phase, a plurality of tuple values are determined in a plurality of calibration steps (C1.1, C1.2, C1.3), and in each of said steps, have a value of the first parameter (TS, LS), a value of the second parameter (TS, QC), and an actual temperature (TW) of the substrate surface obtained from these values, A function (F) representing the actual temperature based on at least one parameter can be defined from the plurality of tuple values using interpolation, and from said function, a value (TW1) of at least one parameter (TC, QC; TS, LS) is obtained, and said value (TW1) correlates with the actual temperature (TW) of the substrate surface that reaches closest to a predetermined substrate temperature, a method for determining parameters for temperature control, characterized in that.

10. The heat input parameter is the set temperature (T Ｓｏ ) of the susceptor. In contrast, the first control loop (23) adjusts the actual temperature (T Ｓ ) of the susceptor or adjusts the heating power (LS) by changing the heating power (LS) supplied to the heating device (6). And / or, the heat dissipation parameter is the set temperature of the cooling device (22), consists of two gases with different thermal conductivities, the mixing ratio of the temperature control gas supplied to the gap (20) between the cooling device (22) and the process chamber ceiling (18), or the set temperature of the process chamber ceiling (T Ｃｏ ), and in contrast, the second control loop (24) adjusts the actual temperature of the process chamber ceiling (T Ｃ ), The method according to claim 9, characterized in that.

11. The method according to claim 9 or 10, wherein a one-dimensional or multi-dimensional function is defined for the execution of the interpolation.

12. That a plurality of said first calibration or adjustment steps directly follow one another, And / or, that a plurality of said calibration or adjustment steps are executed at temperatures that increase or decrease stepwise, and / or, that involve a change in the cooling parameter, the method according to any one of claims 1 to 7 and 9 to 11, characterized in that.

13. The measurement data comprises a substrate temperature (TW) and a process chamber ceiling temperature (TC), In the calibration or adjustment phase (PC), in the heat fluxes (H1, H2, H3, H4) from the heating device (6) towards the cooling device (22), the temperature (TS) and the thermal conductivity are continuously corrected, the method according to any one of claims 1 to 7 and 9 to 12, characterized in that.

14. In several processes that are executed continuously, a substrate is coated in a process phase, calibration or adjustment steps using the same process parameters are executed during respective calibration or adjustment phases (PC), and the measurement data that forms the "feature quantity" is determined exclusively in the calibration or adjustment steps, the method according to any one of claims 1 to 7 and 9 to 13, characterized in that.

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