KR100337107B1 - Temperature Controller for Rapid Thermal Process Apparatus - Google Patents

Abstract

A temperature controller for a rapid heat treatment device is disclosed. A temperature controller for a rapid heat treatment apparatus of the present invention includes a pyrometer and a pyrometer reader for measuring a temperature of a wafer; An auxiliary temperature measuring device for measuring a temperature of the wafer; Each temperature measured from the pyrometer reader and the auxiliary temperature measuring device is input to generate data by comparing and analyzing the respective temperatures input from the pyrometer reader and the auxiliary temperature measuring device to set process temperature. An analyzer for generating a warning signal; It is characterized in that it comprises a controller for receiving the data from the analyzer to adjust the strength of the power supplied to the heat source device. According to the present invention, not only can the wafer temperature and the set process temperature be compared and analyzed during the rapid heat treatment process to generate and monitor data, but also generate a warning signal and a process stop signal when a problem occurs in the process. This prevents the process from proceeding in a state where a problem occurs, thereby improving the yield of semiconductor production, and also detecting errors in the temperature measured from the pyrometer. It is possible to prevent the problem from occurring.

Description

Temperature Controller for Rapid Heat Treatment System {Temperature Controller for Rapid Thermal Process Apparatus}

The present invention relates to a temperature controller for a rapid heat treatment apparatus, and more particularly, to a temperature controller for a rapid heat treatment apparatus capable of monitoring problems occurring during a rapid heat treatment process.

Recently, with increasing integration of semiconductor devices, the size of wafers used in semiconductor devices is increasing, whereas rapid thermal processing is widely used in the manufacture of semiconductor devices because the thermal budget of the semiconductor devices is lowered. In this rapid heat treatment, temperature uniformity over all areas of the wafer is very important for uniform diffusion of the impurity layer injected into the wafer and uniform growth of a material film such as an oxide film.

Figure 1a is a schematic diagram for explaining a conventional rapid heat treatment apparatus, Figure 1b is a schematic diagram for explaining a temperature controller in the rapid heat treatment apparatus according to Figure 1a.

Referring to FIG. 1A, the rapid heat treatment apparatus includes a heat source device 20, a quartz window 30 or a quartz chamber, a temperature controller composed of a pyrometer 41, a temperature controller composed of a temperature controller, and a gas supply unit. .

A tungsten-halogen lamp is mainly used as the heat source device 20, and the wafer 10 is heated by infrared rays emitted from the tungsten-halogen lamp. The quartz window 30 or quartz chamber separates the wafer 10 from the atmosphere, maintains a constant atmosphere during the rapid heat treatment process, protects the wafer 10 from contaminants such as dust in the air, and heat source. It serves to transmit the infrared radiation emitted from the device 20.

The temperature measuring unit mainly uses a pyrometer 41 to quickly measure the temperature of the wafer 10 in a non-contact manner. The pyrometer 41 detects the intensity of a specific wavelength emitted from the wafer 10 by heating.

Referring to FIG. 1B, the wavelength detected by the pyrometer 41 is read as a temperature by the pyrometer reader 42, and when the read temperature is input to the temperature controller 50, the temperature controller 50 determines that the temperature is controlled. In order to match the temperature of the wafer 10 with the temperature specified in the set process conditions, that is, recipe (Recipe), the comparison control value is output. The power controller 60 receives the signal output from the temperature controller 50 and supplies the controlled power to the heat source device 20.

Accurate measurement of wafer temperature in such a rapid thermal processing apparatus is a very important factor in determining the reliability of the rapid thermal processing process and the quality of the semiconductor device, so the performance of the pyrometer is very important. However, the pyrometer is very sensitive to the wafer state during the process, ie the emissivity with temperature, the geometry of the chamber, the spectral wavelength of the pyrometer, and the type and thickness of the thin film formed on the wafer. It works.

Therefore, not only the temperature detected by the pyrometer is changed by various conditions during the process, but also the error range of the temperature due to the distance between the pyrometer and the wafer and the contamination of the measuring part in the pyrometer is ± In the rapid heat treatment process that must maintain the accuracy of less than 1 ℃ causes a lot of obstacles in the temperature uniformity on the wafer or the formation of temperature uniformity between the wafers. Therefore, in order to clean the chamber during the initial installation and to remove the pyrometer from the chamber and then remount it, the error correction procedure is required on a regular basis.

However, despite the periodic error correction procedure of the pyrometer, many problems are caused by the error of the temperature detected in the temperature detection using the pyrometer. This is because, due to the characteristics of the rapid heat treatment process, the result of the process cannot be directly confirmed immediately after the rapid heat treatment process, and the problem of the heat treatment process can be found only after the wafer is finally completed. Thus, this is a big obstacle in improving wafer yield.

Therefore, the technical task of the present invention is to not only monitor the wafer temperature and the set process temperature during the heat treatment process, but also improve the reliability of the measured wafer temperature, and to measure the temperature measured from the pyrometer. The present invention provides a temperature controller for a rapid heat treatment device capable of identifying an error.

1A is a schematic view for explaining a conventional rapid heat treatment apparatus;

1B is a schematic diagram for explaining a temperature controller in the rapid heat treatment apparatus according to FIG. 1A;

2A is a schematic diagram for explaining a temperature controller for a rapid heat treatment apparatus of the present invention;

2b and 2c are respective graphs showing a temperature change with respect to time measured from a pyrometer and a temperature change with time measured from a thermocouple in the temperature controller for the rapid heat treatment apparatus according to FIG. 2a.

Explanation of symbols on the main parts of the drawings

110: pyrometer 120: pyrometer reader

210: thermocouple 220: thermocouple converter

300: Analyzer

410: main controller 420: power controller

The temperature controller for the rapid thermal processing apparatus of the present invention for achieving the above technical problem, and a pyrometer and pyrometer reader for measuring the temperature of the wafer; An auxiliary temperature measuring device installed to generate a constant deviation between the temperature measured by the pyrometer and the temperature of the wafer measured by the pyrometer; Receives the respective temperatures measured from the pyrometer and the auxiliary temperature measuring device and compares and analyzes each of the temperatures input from the pyrometer reader and the auxiliary temperature measuring device and the set process temperature to obtain data, a process stop signal, and An analyzer for generating a warning signal and generating the process stop signal and the warning signal when the temperature measured by the pyrometer and the temperature measured by the auxiliary temperature measuring device deviate from a certain deviation; And a controller for receiving data from the analyzer and adjusting the intensity of power supplied to the heat source device.

In this case, the auxiliary temperature measuring device may be composed of a thermocouple and a thermocouple converter.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Figure 2a is a schematic diagram for explaining the temperature controller for a rapid heat treatment apparatus of the present invention, Figures 2b and 2c is a process condition set in the temperature controller for a rapid heat treatment apparatus according to Figure 2a, that is measured in the temperature change rate and thermocouple over time Each graph shows a change in temperature over time.

Referring to FIG. 2A, the pyrometer 110 and the thermocouple 210 are spaced apart from the wafer 10 seated in the rapid thermal processing apparatus, and the pyrometer 110 has a pyrometer reader 120 installed therein. The thermocouple 210 is provided with a thermocouple converter 220. Generally, the thermocouple 210 is installed in contact with the wafer 10, but not only generates a constant deviation between the temperature measured by the pyrometer 110 and the temperature measured by the thermocouple 210, but also rotates the wafer 10. The thermocouple 210 is installed away from the wafer 10 in order to easily detect the temperature and avoid incidental problems caused by contact. The wavelength of the wafer 10 measured at the pyrometer 110 is read as temperature in the pyrometer reader 120, and the electromotive force generated in the thermocouple 210 is converted to temperature in the thermocouple converter 220. The temperatures read and converted by the pyrometer reader 120 and the thermocouple converter 220 are input to the temperature analyzer 300, respectively. At this time, the temperature read by the pyrometer reader 120 and the temperature converted by the thermocouple converter 220 may have a constant deviation.

In FIG. 2A, reference numeral 'A' is an enlarged view of the thermocouple 210. Referring to reference numeral 'A', the thermocouple 210 may include a thermocouple element wire 211, a thermocouple protective film 212 surrounding the thermocouple element wire 211, and a thermocouple compensation lead connected to one end of the thermocouple element wire 211 ( 214, a sealing connector 213 installed at a connection portion of the thermocouple element wire 211 and the thermocouple compensation lead wire 214, and the thermocouple compensation lead wire 214 in order to block the thermocouple element wire 211 from the outside. The thermocouple connector 215 transfers a signal output from the compensating lead 214 to the thermocouple converter 220. Here, the thermocouple protective film 212 is a material that can withstand the oxidation and high temperature without extending the reaction rate of the thermocouple element 211 to prevent the thermocouple element wire 211 is deteriorated and oxidized by the gas inside the chamber. do.

The analyzer 300 analyzes each of the temperatures input to the analyzer 300 in a predetermined process condition, for example, temperature change with respect to time, generates data, and then outputs the data to the main controller 410. The analyzed data is monitored by the analyzer 300. Meanwhile, the analyzer 300 compares the temperature change with respect to the set process time and the temperature change with respect to the time measured by the pyrometer 110 and the thermocouple 210 during the process from the beginning of the process to cause an abnormality. In other words, when the respective temperatures measured from the pyrometer and the thermocouple are out of the preset error range from the set process temperature, the process stop signal and the warning signal are generated. As such, when the analyzer 300 generates a warning signal or a process stop signal when a problem occurs in the process, the process may be prevented from continuing in the state where the problem occurs. In addition, by measuring the temperature of the wafer using a pyrometer and a thermocouple having different characteristics from the pyrometer, the reliability of the measured wafer temperature is improved.

On the other hand, when the wafer temperature measured in the pyrometer and the set temperature is the same, the graph (ⓐ) showing the rate of change of temperature with respect to the time measured from the pyrometer and the process conditions set with reference to Fig. 2b and temperature change rate in the thermocouple Comparing the graph (ⓑ), the temperature measured from the thermocouple at a particular time zone (A) shows a constant deviation from the temperature specified in the set process conditions. This deviation may vary depending on the method of construction, structure, material, distance from the wafer, and the like. For example, when monitoring the process by comparing the temperature measured from the thermocouple in the 'A' section with the temperature measured from the pyrometer, the temperature to be measured from the thermocouple in the 'A' section is derived by experiment in advance. The values of the temperature, the tolerance range and the warning range are assigned to the analyzer 300.

2C is an enlarged view of a section 'A' in the graph according to FIG. 2B. In FIG. 2C, ⓐ and ⓑ are graphs showing temperatures measured from a pyrometer and a thermocouple in a section 'A' as in FIG. 2B, respectively. Reference numerals 1 and 2 formed up and down centering on the b graph in FIG. 2C indicate an allowable range region, and 2 indicates a warning signal generation region.

Referring to FIG. 2C, when the temperature deviation measured by the pyrometer and thermocouple is constant as shown in FIG. . The warning signal generation area ② is 420 to 440 ° C and 460 to 480 ° C, and the process stop signal generation area is 420 ° C or less and 480 ° C or more. Accordingly, during the process, the analyzer compares and analyzes the temperature of the designated 'A' section (450 ° C.) with the temperature measured from the thermocouple to determine whether the process continues and whether a warning signal or a process stop signal is generated.

If the temperature measured from the thermocouple in the 'A' section is outside the permissible range (①) and enters the warning signal generating area (②), there is no serious problem in the process, but since the equipment needs to be checked, the analyzer generates a warning signal. Continues. When the temperature measured in the thermocouple enters the process stop signal generation region, the analyzer generates a process stop signal and stops the process. At this time, the user stops the process for production and checks and measures the temperature measurement and control part of the equipment.

As such, by analyzing the temperature measured by the pyrometer and the temperature measured by the thermocouple to generate a warning signal and a process stop signal, the calibration procedure of the pyrometer is immediately performed without the progress of the post process.

Meanwhile, in the present exemplary embodiment, a warning signal or a process stop signal is generated by using a deviation of the temperature measured from the pyrometer and the thermocouple and a specific allowable temperature range among the set process conditions, but are not necessarily limited thereto.

Referring again to FIG. 2A, when the main controller 410 receives data from the analyzer 300 and generates a signal for adjusting the intensity of power supplied to the heat source device 20, the main controller 420 may control the power controller 420. By receiving a signal from the 410 to increase or decrease the power supplied to the heat source device 20 to maintain the temperature of the substrate 10 in the set process conditions.

As described above, according to the temperature controller for the rapid heat treatment apparatus of the present invention, not only can the data be generated and monitored by comparing and analyzing the wafer temperature and the set process temperature during the rapid heat treatment process, but also there is a problem in the process. By generating a warning signal and a process stop signal when it occurs, it is possible to prevent the process from proceeding in a state where a problem occurs, thereby improving the production yield of the semiconductor.

In addition, by measuring the temperature of the wafer using a pyrometer and an auxiliary temperature measuring device having different characteristics from the pyrometer, it is possible to improve the reliability of the measured wafer temperature and to identify the error of the temperature measured from the pyrometer. This can prevent problems caused by incorrect temperature measurement from the pyrometer.

The present invention is not limited only to the above embodiments, and it is apparent that many modifications are possible by those skilled in the art within the technical spirit of the present invention.

Claims (4)

A temperature controller for a rapid heat treatment apparatus for rapidly heat treating a wafer by a heat source device at a set process temperature; A pyrometer and a pyrometer reader for measuring the temperature of the wafer; An auxiliary temperature measuring device installed to generate a constant deviation between the temperature measured by the pyrometer and the temperature of the wafer measured by the pyrometer; Receives the respective temperatures measured from the pyrometer and the auxiliary temperature measuring device and compares and analyzes each of the temperatures input from the pyrometer reader and the auxiliary temperature measuring device and the set process temperature to obtain data, a process stop signal, and An analyzer for generating a warning signal and generating the process stop signal and the warning signal when the temperature measured by the pyrometer and the temperature measured by the auxiliary temperature measuring device deviate from a certain deviation; And a controller for receiving data from the analyzer and adjusting the intensity of power supplied to the heat source device. delete The temperature controller of claim 1, wherein the auxiliary temperature measuring device comprises a thermocouple and a thermocouple converter. delete