Furnace tube internal temperature monitoring device
By setting up a pyrometer in the furnace tube to receive thermal radiation and monitor the temperature of the top and bottom of the furnace tube, the problem of temperature control deviation in the prior art is solved, and precise control of the temperature in the furnace tube and the improvement of product qualification rate are achieved.
Patent Information
- Application Number
- CN202420787035.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-16
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-04-16
AI Technical Summary
The existing thermal oxidation furnace tube temperature monitoring device cannot accurately monitor the temperature in the top and bottom areas of the furnace tube, resulting in temperature control deviations and affecting process quality and product yield.
A temperature monitoring device in the furnace tube is designed. By setting up a first pyrometer and a second pyrometer to receive the thermal radiation of the wafer at the top and bottom of the wafer respectively, it monitors the temperature of the top and bottom of the furnace tube in real time, and combines traditional temperature sensors and thermocouple probes to achieve temperature measurement of each area of the furnace tube.
It realizes intuitive and precise regulation of the temperature in the furnace tube, ensures the temperature required by the process, improves the product's pass rate, and reduces production costs.
Smart Images
Figure CN222865621U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a temperature monitoring device in a furnace tube. Background Art
[0002] In the process of manufacturing semiconductor devices, furnace tubes are important thermal oxidation equipment. The core of the planar process is to grow a SiO2 layer on the silicon surface. The formed SiO2 layer can be tightly attached to the surface of the silicon substrate and has good chemical stability and electrical insulation. It is often used as a barrier layer or dielectric isolation layer for diffusion and ion implantation. Thermal oxidation growth technology refers to the chemical reaction of silicon with oxidants such as oxygen or water vapor at high temperature to generate SiO2. The silicon in the thermally oxidized SiO2 comes from the silicon surface. The thermal oxidation growth process usually puts batches of silicon wafers into a clean quartz furnace tube. The quartz furnace tube is generally heated to 200-1800℃, and the oxidant (such as dry oxygen or pure water vapor) is introduced from one end of the furnace tube at normal pressure and discharged from the other end.
[0003] The traditional thermal oxidation furnace tube temperature control is generally to monitor the temperature of the quartz furnace tube surface through a temperature sensor, and at the same time, to extend a thermocouple probe into the quartz furnace tube to measure the temperature at different heights in the furnace tube, and then compare the temperature difference, and adjust the heating module according to the temperature difference to make the temperature inside the quartz furnace tube meet the process requirements. However, these two methods cannot monitor the temperature of the top and bottom areas of the furnace tube. Generally, due to factors such as the flow rate of the oxidant in the furnace tube, the temperature of different areas in the furnace tube varies, which leads to deviations in the furnace tube temperature control. Since the furnace tube has high requirements for temperature accuracy, any temperature deviation will cause defects in the process, resulting in reduced product yields, and thus increased production costs. Utility Model Content
[0004] The utility model aims to provide a furnace tube temperature monitoring device to solve the problem of insufficient accuracy of the existing thermal oxidation furnace tube temperature monitoring device.
[0005] In order to achieve the above object, the utility model provides a furnace tube temperature monitoring device for monitoring the internal temperature of the furnace tube, wherein the furnace tube is arranged on a base, and a wafer boat is arranged in the furnace tube, and a plurality of wafers are placed in parallel on the wafer boat along the height direction, and the furnace tube temperature monitoring device comprises:
[0006] a first temperature measurement module, arranged at the top of the furnace tube, comprising a first pyrometer and a radiation conduction window, wherein the first pyrometer is located outside the furnace tube, the radiation conduction window is arranged on the top wall of the furnace tube, and the thermal radiation on the surface of the wafer located at the top of the wafer boat is transmitted to the first pyrometer through the radiation conduction window, and the first pyrometer outputs the top temperature of the furnace tube based on the received thermal radiation;
[0007] The second temperature measurement module includes a second pyrometer, which is arranged on the base and extends into the furnace tube. The second pyrometer is used to receive thermal radiation from the surface of the wafer located at the bottom of the wafer boat and output the bottom temperature of the furnace tube based on the received thermal radiation.
[0008] Optionally, the first pyrometer and the radiation conduction window are located on the same vertical line.
[0009] Optionally, the radiation conduction window is directly opposite to the center of the wafer located at the top of the wafer boat.
[0010] Optionally, the radiation conduction window is made of a transparent and high temperature resistant material.
[0011] Optionally, the radiation conduction window is made of aluminum oxide.
[0012] Optionally, the furnace tube temperature monitoring device further includes a control module, wherein the control module is electrically connected to the first pyrometer and the second pyrometer, and the control module is used to obtain the temperatures measured by the first pyrometer and the second pyrometer in real time.
[0013] Optionally, a heating module is provided outside the furnace tube, and the heating module is electrically connected to the control module. The control module sends a control signal to the heating module based on the temperature difference measured by the first pyrometer and the pyrometer, and the heating module adjusts the temperature inside the furnace tube according to the control signal.
[0014] Optionally, the heating module includes a heating resistance wire arranged around the outside of the furnace tube, and the first pyrometer is embedded in the heating resistance wire through a heat insulation sheet.
[0015] Optionally, the furnace tube temperature monitoring device further includes a display module, which is electrically connected to the control module and is used to display the temperatures measured by the first pyrometer and the second pyrometer.
[0016] Optionally, the temperature monitoring device in the furnace tube also includes multiple temperature sensors and a thermocouple unit, the multiple temperature sensors are arranged on the outer wall of the furnace tube along the height direction, and the thermocouple unit extends into the furnace tube and has multiple thermocouple probes arranged on the outside of the crystal boat along the height direction.
[0017] The furnace tube temperature monitoring device provided by the utility model has at least one of the following beneficial effects:
[0018] 1) The first pyrometer and the second pyrometer are respectively arranged to receive the thermal radiation of the wafers at the top and bottom of the wafer boat to monitor the top temperature and the bottom temperature of the furnace tube in real time. The temperature of each area of the furnace tube can be measured in combination with the traditional temperature sensor and the thermocouple probe, so as to facilitate the intuitive and precise control of the temperature in the furnace tube to ensure the temperature required by the process, thereby ensuring the smooth progress of the process and improving the qualified rate of the product;
[0019] 2) The top and bottom temperatures of the furnace tube are monitored online by configuring the control module, the first temperature measurement module and the second temperature measurement module, and the temperature of the furnace tube is automatically adjusted in cooperation with the heating module to ensure the temperature required by the process. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Those skilled in the art should understand that the drawings provided are for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.
[0021] Figure 1 This is a schematic structural diagram of a furnace tube temperature monitoring device provided in one embodiment of the utility model.
[0022] in:
[0023] 1-furnace tube; 2-base; 3-wafer boat; 4-wafer; 5-first pyrometer; 6-radiation conduction window; 7-second pyrometer; 8-temperature sensor; 9-thermocouple unit; 10-control module; 11-heating module. DETAILED DESCRIPTION
[0024] In order to make the purpose, advantages and features of the present utility model clearer, the present utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the implementation method of the present utility model. In order to make the purpose, features and advantages of the present utility model more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present utility model. Any modification of the structure, change in the proportional relationship or adjustment of the size, in the case of the same or similar effects and purposes that can be achieved by the present utility model, should still fall within the scope of the technical content disclosed by the present utility model.
[0025] As used in the present invention, the singular forms "one", "an", and "the" include plural objects, unless the content clearly indicates otherwise. As used in the present invention, the term "or" is generally used in a sense that includes "and / or", unless the content clearly indicates otherwise. As used in the present invention, the term "several" is generally used in a sense that includes "at least one", unless the content clearly indicates otherwise. As used in the present invention, the term "at least two" is generally used in a sense that includes "two or more", unless the content clearly indicates otherwise. In addition, the terms "first", "second", and "third" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features.
[0026] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0027] Please refer to Figure 1 The present embodiment provides a furnace tube temperature monitoring device for monitoring the internal temperature of a furnace tube 1. The furnace tube 1 is disposed on a base 2, and a wafer boat 3 is disposed in the furnace tube 1. The wafer boat 3 has a plurality of wafers 4 placed in parallel along a height direction. The furnace tube temperature monitoring device includes:
[0028] A first temperature measurement module is arranged at the top of the furnace tube 1. The first temperature measurement module includes a first pyrometer 5 and a radiation conduction window 6. The first pyrometer 5 is located outside the furnace tube 1. The radiation conduction window 6 is arranged on the top wall of the furnace tube 1. The thermal radiation on the surface of the wafer 4 located at the top of the wafer boat 3 is transmitted to the first pyrometer 5 through the radiation conduction window 6. The first pyrometer 5 outputs the top temperature of the furnace tube 1 based on the received thermal radiation;
[0029] The second temperature measurement module includes a second pyrometer 7, which is arranged on the base 2 and extends into the furnace tube 1. The second pyrometer 7 is used to receive thermal radiation from the surface of the wafer 4 located at the bottom of the wafer boat 3, and output the bottom temperature of the furnace tube 1 based on the received thermal radiation.
[0030] By arranging the first pyrometer 5 and the second pyrometer 7 to receive the thermal radiation of the wafer 4 located at the top and the bottom of the wafer boat 3 respectively, the top temperature and the bottom temperature of the furnace tube 1 can be monitored in real time. In combination with traditional temperature sensors and thermocouple probes, the temperature measurement of each area of the furnace tube 1 can be realized, thereby facilitating the intuitive and precise regulation of the temperature in the furnace tube 1 to ensure the temperature required for the process, thereby ensuring the smooth progress of the process and improving the qualified rate of the product.
[0031] In this embodiment, the temperature monitoring device inside the furnace tube also includes multiple temperature sensors 8 and a thermocouple unit 9. The multiple temperature sensors 8 are arranged on the outer wall of the furnace tube 1 along the height direction. The thermocouple unit 9 extends into the furnace tube 1 and has multiple thermocouple probes arranged on the outside of the crystal boat 3 along the height direction.
[0032] It should be understood that when the furnace tube 1 is used for the thermal oxidation growth process, based on the different sizes of the furnace tube 1 and the wafer boat 3, the flow rates of the oxidant at different heights in the furnace tube 1 are different, resulting in different temperatures at different heights in the furnace tube 1. The traditional temperature sensor 8 and the thermocouple probe 9 are unable to monitor the temperatures of the top and bottom areas of the furnace tube 1. Therefore, this embodiment measures the top and bottom temperatures of the furnace tube 1 respectively, and analyzes and processes the data based on the two temperature measurement modules. It is possible to obtain a more accurate temperature in the furnace tube 1, reduce product errors caused by temperature errors in the process, and thus improve the product yield.
[0033] Preferably, the first pyrometer 5 and the radiation conduction window 6 are located on the same vertical line, so that the temperature measured by the first pyrometer 5 is more accurate.
[0034] Preferably, the radiation conducting window 6 faces the center of the wafer 4 located at the top of the wafer boat 3 .
[0035] In this embodiment, since a base 2 is usually provided at the bottom of the furnace tube 1, the second pyrometer 7 can be directly set on the base 2 and extended into the furnace tube 1, thereby directly receiving thermal radiation from the surface of the wafer 4 located at the bottom of the wafer boat 3, without the need to additionally set up a radiation conduction window 6.
[0036] Preferably, the radiation conduction window 6 is made of a transparent and high temperature resistant material. The radiation conduction window 6 is mainly used as an intermediate window for heat radiation to flow through, and it can be made of a transparent and high temperature resistant material. In this embodiment, the radiation conduction window 6 is made of aluminum oxide, which has high hardness and is transparent throughout.
[0037] In this embodiment, the number of first temperature measurement modules can be one or more, and the utility model does not impose any restrictions on this. When there are multiple first temperature measurement modules, the multiple first temperature measurement modules can be arranged in a direction parallel to the wafer 4, and can be distributed at equal intervals or configured according to other rules, and the utility model does not impose any restrictions on this.
[0038] Similarly, the number of second temperature measurement modules can be one or more, and the utility model does not impose any restrictions on this. When there are multiple second temperature measurement modules, the multiple second temperature measurement modules can be arranged in a direction parallel to the wafer 4, and can be distributed at equal intervals or configured according to other rules. The utility model does not impose any restrictions on this.
[0039] In this embodiment, the furnace tube temperature monitoring device further includes a control module 10, which is electrically connected to the first pyrometer 5 and the second pyrometer 7, and is used to obtain in real time the temperatures measured by the first pyrometer 5 and the second pyrometer 7. The control module 10 includes but is not limited to a PLC, which can be used to analyze and process the temperatures fed back by the first pyrometer 5 and the second pyrometer 7, perform online monitoring, and perform data storage.
[0040] In this embodiment, a heating module 11 is provided outside the furnace tube 1, and the heating module 11 is electrically connected to the control module 10. The control module 10 sends a control signal to the heating module 11 based on the temperature measured by the first pyrometer 5 and the second pyrometer 7, and the heating module 11 adjusts the temperature in the furnace tube 1 according to the control signal. The top and bottom temperatures in the furnace tube 1 are monitored online by configuring the control module 10, the first temperature measuring module and the second temperature measuring module, and the temperature in the furnace tube 1 is automatically controlled in cooperation with the heating module 11 to ensure the temperature required by the process, thereby ensuring the smooth progress of the process and improving the qualified rate of the product.
[0041] In this embodiment, the heating module 11 includes a heating resistance wire arranged around the outside of the furnace tube 1, and the first pyrometer 5 is embedded in the heating resistance wire through a heat insulation sheet. It should be understood that, based on the different heights of the furnace tube 1, there can be one heating module 11, or multiple heating modules 11 can be configured along the circumference of the furnace tube 1 to heat different positions of the furnace tube 1 respectively. The heating module 11 is usually designed as a heating resistance wire spirally wrapped around the outside of the furnace tube 1, and the first pyrometer 5 can be directly sandwiched in the gap of the heating resistance wire through a heat insulation sheet.
[0042] Preferably, the temperature monitoring device in the furnace tube also includes a display module, which is electrically connected to the control module 10 and is used to display the temperatures measured by the first pyrometer 5 and the second pyrometer 7. Of course, the display module can also be used to display the temperatures measured by the temperature sensor 8 and the thermocouple probe 9, and the utility model does not limit this.
[0043] In summary, the embodiment of the utility model provides a device for monitoring the temperature inside a furnace tube, by arranging a first pyrometer 5 and a second pyrometer 7 to receive the thermal radiation of the wafer 4 located at the top and the bottom of the wafer boat 3 respectively, so as to monitor the top temperature and the bottom temperature of the furnace tube 1 in real time, and in combination with traditional temperature sensors and thermocouple probes, the temperature measurement of each area of the furnace tube 1 can be realized, thereby facilitating the intuitive and precise regulation of the temperature inside the furnace tube 1, ensuring the temperature required by the process, thereby ensuring the smooth progress of the process and improving the qualified rate of the product.
[0044] In addition, it should be recognized that although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the above disclosed technical content can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.
Claims
1. A temperature monitoring device in a furnace tube, used for monitoring the internal temperature of the furnace tube, wherein the furnace tube is arranged on a base, and a wafer boat is arranged in the furnace tube, and a plurality of wafers are placed in parallel in the height direction of the wafer boat, characterized in that: The furnace tube temperature monitoring device comprises: a first temperature measurement module, arranged at the top of the furnace tube, comprising a first pyrometer and a radiation conduction window, wherein the first pyrometer is located outside the furnace tube, the radiation conduction window is arranged on the top wall of the furnace tube, and the thermal radiation on the surface of the wafer located at the top of the wafer boat is transmitted to the first pyrometer through the radiation conduction window, and the first pyrometer outputs the top temperature of the furnace tube based on the received thermal radiation; The second temperature measurement module includes a second pyrometer, which is arranged on the base and extends into the furnace tube. The second pyrometer is used to receive thermal radiation from the surface of the wafer located at the bottom of the wafer boat and output the bottom temperature of the furnace tube based on the received thermal radiation.
2. The furnace tube temperature monitoring device according to claim 1, characterized in that: The first pyrometer and the radiation conduction window are located on the same vertical line.
3. The furnace tube temperature monitoring device according to claim 1 or 2, characterized in that: The radiation conduction window is directly opposite to the center of the wafer located at the top of the wafer boat.
4. The furnace tube temperature monitoring device according to claim 1, characterized in that: The radiation conduction window is made of transparent and high temperature resistant material.
5. The furnace tube temperature monitoring device according to claim 4, characterized in that: The radiation conduction window is made of aluminum oxide.
6. The furnace tube temperature monitoring device according to claim 1, characterized in that: The furnace tube temperature monitoring device further includes a control module, which is electrically connected to the first pyrometer and the second pyrometer, and is used to obtain the temperatures measured by the first pyrometer and the second pyrometer in real time.
7. The furnace tube temperature monitoring device according to claim 6, characterized in that: A heating module is provided outside the furnace tube and is electrically connected to the control module. The control module sends a control signal to the heating module based on the temperature difference measured by the first pyrometer and the pyrometer, and the heating module adjusts the temperature inside the furnace tube according to the control signal.
8. The furnace tube temperature monitoring device according to claim 7, characterized in that: The heating module comprises a heating resistance wire which is arranged around the outside of the furnace tube, and the first pyrometer is embedded in the heating resistance wire through a heat insulation sheet.
9. The furnace tube temperature monitoring device according to claim 6, characterized in that: The furnace tube temperature monitoring device further includes a display module, which is electrically connected to the control module and is used to display the temperatures measured by the first pyrometer and the second pyrometer.
10. The furnace tube temperature monitoring device according to claim 1, characterized in that: The temperature monitoring device in the furnace tube also includes multiple temperature sensors and a thermocouple unit. The multiple temperature sensors are arranged on the outer wall of the furnace tube along the height direction. The thermocouple unit extends into the furnace tube and has multiple thermocouple probes arranged on the outside of the crystal boat along the height direction.