On-chip and off-chip wafer temperature measuring device for semiconductor manufacturing

Abstract

The invention provides an on-chip and off-chip wafer temperature measuring device for semiconductor manufacturing, and relates to the technical field of semiconductor manufacturing. The device comprises a temperature measuring wafer, a transmission wire connected with the temperature measuring wafer, a vacuum penetrating belt located on the outer side of the transmission wire, a temperature measuring wafer data acquisition instrument connected with the transmission wire, a signal receiving device remotely connected with the temperature measuring wafer data acquisition instrument and an upper computer. The temperature measuring wafer is provided with a conventional temperature measuring point and a key temperature measuring point; conventional thermocouple temperature measurement sensors are arranged at the conventional temperature measurement points; integrated thermocouple temperature measurement sensors are uniformly distributed on the surface and inside the key temperature measurement point; a groove is arranged in the key temperature measurement point, and the integrated thermocouple temperature measurement sensor is arranged in the key temperature measurement point through the groove. According to the invention, the problem of low temperature measurement precision of the thermocouple wafer is solved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to an on-chip and off-chip wafer temperature measurement device used in semiconductor manufacturing. Background Art

[0002] In the field of semiconductor manufacturing, wafers often need to be heated to above 1000°C, so it is very necessary to monitor the temperature of the wafer surface. In addition, accurate measurement of wafer surface temperature helps optimize process manufacturing levels and promote the development of the semiconductor manufacturing industry. Commonly used wafer temperature measurement methods include resistance temperature measurement, thermocouple temperature measurement, and fluorescent fiber temperature measurement. Among them, resistance temperature measurement is more difficult to measure at high temperatures and has a poor reproducibility level; fluorescent fiber temperature measurement has higher accuracy below 200°C, but it is difficult to perform contact measurement at higher temperatures due to factors such as materials, and the non-contact measurement level is relatively poor; thermocouple temperature measurement technology is the most mature wafer temperature measurement technology among the three. This technology is based on the Seebeck effect between two conductors or semiconductors to measure wafer temperature.

[0003] The thermocouples used in traditional thermocouple temperature measurement technology are mainly K-type / S-type thermocouples, and the temperature measurement uncertainty is between ±1.5℃~2.5℃, which is relatively high. During the measurement process, the thermocouples are generally arranged on the surface of the object to be measured, and can only obtain the temperature of the surface of the object, which has certain temperature measurement limitations. In addition, during the actual temperature measurement of the wafer, the contact between the thermocouple and the wafer surface will produce contact thermal resistance, and the existence of contact thermal resistance will cause errors between the temperature measurement result and the actual temperature value of the wafer surface. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art and the particularity of the use scenarios of temperature measuring wafers, the present invention provides an on-chip and off-chip wafer temperature measuring device for semiconductor manufacturing, which solves the problem of measurement error and correction introduced by contact thermal resistance of thermocouple temperature measuring wafers.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is: a wafer temperature measurement device for on-chip and off-chip wafers used in semiconductor manufacturing, comprising: a temperature measurement wafer, a transmission wire connected to the temperature measurement wafer, a vacuum penetration belt located outside the transmission wire, a temperature measurement wafer data acquisition instrument connected to the transmission wire, a signal receiving device and a host computer remotely connected to the temperature measurement wafer data acquisition instrument; Conventional temperature measurement points and key temperature measurement points are arranged on the temperature measurement wafer; conventional thermocouple temperature measurement sensors are arranged at the conventional temperature measurement points; integrated thermocouple temperature measurement sensors are arranged on the surface and inside of the key temperature measurement points; grooves are arranged inside the key temperature measurement points, and the integrated thermocouple temperature measurement sensors are arranged inside the key temperature measurement points through the grooves.

[0006] The beneficial effects of the present invention are as follows: the present invention sets grooves on the surface of the wafer, arranges thermocouple temperature measuring sensors inside the grooves and on the surface after filling of the wafer, so that the temperature measuring wafer has the ability to measure the temperature at the temperature measuring point on and off the wafer; by measuring the temperature of the wafer surface and the inside of the wafer, the contact thermal resistance generated by the contact between the thermocouple wire and the surface of the wafer to be measured is quantitatively calculated, thereby greatly reducing the temperature measurement error caused by the contact thermal resistance; by designing the groove cross-section on the wafer surface as a superposition of a circle and a rectangle, it is beneficial to the subsequent filling of silicon-based materials and to increase the contact length between the wire and the wafer, thereby reducing the measurement error of the thermocouple sensor caused by heat transfer of the wire.

[0007] Furthermore, the inside of the groove at the key temperature measurement point and the space between the integrated thermocouple temperature measurement sensors on the groove surface are filled with silicon-based materials; the groove is a structure with a depth of 200 μm to 400 μm and a shape that is a superposition of a circle and a rectangle.

[0008] Furthermore, the filling height of the silicon-based material is consistent with the surface height of the temperature measuring wafer.

[0009] Furthermore, the temperature measurement points of the temperature measurement wafer are evenly distributed in a ring shape; wherein the temperature measurement points include conventional temperature measurement points and key temperature measurement points, and the conventional temperature measurement points and the key temperature measurement points are evenly distributed or regionally distributed.

[0010] Integrated thermocouples are arranged at key points on the wafer surface, and the temperature measurement points on the wafer surface are evenly distributed in a ring shape, which can meet the actual temperature measurement needs on site, ensure temperature measurement accuracy, and reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein: Figure 1 is an exemplary schematic diagram of an on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing according to some embodiments of this specification; FIG. 2 ( a ) is an exemplary schematic diagram of uniformly distributed temperature measurement points on the surface of a temperature measurement wafer according to some embodiments of this specification; FIG2( b ) is an exemplary schematic diagram of the regional distribution of temperature measurement points on the surface of a temperature-measured wafer according to some embodiments of this specification; Figure 3 is an exemplary schematic diagram of a temperature measurement wafer trench cross section according to some embodiments of this specification; Among them: 1. Temperature measuring wafer; 2. Integrated thermocouple temperature measuring sensor; 3. Conventional thermocouple temperature measuring sensor; 4. Transmission wire; 5. Vacuum penetration belt; 6. Temperature measuring wafer data acquisition instrument; 7. Signal receiving device; 8. Host computer. DETAILED DESCRIPTION

[0012] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0013] Example Figure 1 It is an exemplary schematic diagram of an on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing according to some embodiments of the present specification.

[0014] In some embodiments, Figure 1 As shown, a wafer temperature measurement device for on-chip and off-chip wafers used in semiconductor manufacturing may include a temperature measurement wafer 1, a transmission wire 4 connected to the temperature measurement wafer 1, a vacuum penetration belt 5 located outside the transmission wire 4, a temperature measurement wafer data acquisition instrument 6 connected to the transmission wire 4, a signal receiving device 7 remotely connected to the temperature measurement wafer data acquisition instrument 6, and a host computer 8; Conventional temperature measurement points and key temperature measurement points are provided on the temperature measurement wafer 1; conventional thermocouple temperature measurement sensors 3 are arranged at the conventional temperature measurement points; integrated thermocouple temperature measurement sensors 2 are evenly arranged on the surface and inside of the key temperature measurement points; grooves are arranged inside the key temperature measurement points, and the integrated thermocouple temperature measurement sensors 2 are arranged inside the key temperature measurement points through the grooves.

[0015] In some embodiments, the material of the transmission wire 4 may preferably be K-type, S-type, R-type or other thermocouple wires.

[0016] By selecting the material of the dual wire, it can better adapt to the measurement temperature range and measurement accuracy requirements.

[0017] In some embodiments, the material of the vacuum penetration belt 5 may preferably be composed of an alumina fiber sleeve.

[0018] By selecting this material, the high temperature resistance, corrosion resistance and thermal shock resistance of the vacuum penetration belt 5 can be improved, thereby ensuring the stability of the temperature measurement result to the greatest extent.

[0019] In some embodiments, as shown in FIG. 2 (a) and FIG. 2 (b), the temperature measurement points of the temperature measurement wafer 1 are evenly distributed in a ring shape of (8, 8, 1); wherein the temperature measurement points include conventional temperature measurement points and key temperature measurement points, and the conventional temperature measurement points and the key temperature measurement points are evenly distributed or regionally distributed.

[0020] In some embodiments of the present specification, integrated thermocouples are arranged at key points on the wafer surface, and the temperature measurement points on the wafer surface are evenly distributed in a ring shape of (8, 8, 1), which can meet actual temperature measurement requirements on site, ensure temperature measurement accuracy, and reduce costs.

[0021] In some embodiments, conventional temperature measurement points and key temperature measurement points can be set according to on-site temperature measurement requirements.

[0022] In some embodiments of the present specification, the temperature measurement points are set according to the on-site temperature measurement requirements so that the temperature measurement results can better match the actual measurement requirements.

[0023] In some embodiments, the distribution of temperature measurement points can be selected according to actual conditions. For example, when it is necessary to better reflect the actual temperature distribution on the wafer surface, a uniform distribution can be used, as shown in FIG2 (a), and the key temperature measurement points of the outer ring and the inner ring are staggered according to the uniform distribution; when it is necessary to measure the temperature in the key temperature measurement area in detail, a regional distribution can be used, as shown in FIG2 (b), and all the temperature measurement points in the key temperature measurement area are set as key temperature measurement points.

[0024] In some embodiments of the present specification, the measurement points are evenly distributed on the entire wafer surface, which can effectively ensure the flatness of the wafer surface and improve the accuracy of temperature measurement.

[0025] In some embodiments, the integrated thermocouple temperature sensor 2 is bonded to the temperature measuring wafer 1 based on key temperature measuring points, and the conventional thermocouple temperature sensor 3 is bonded to the temperature measuring wafer 1 based on conventional temperature measuring points.

[0026] In some embodiments, the integrated thermocouple temperature sensor 2 and the conventional thermocouple temperature sensor 3 form a wafer temperature measurement system for acquiring temperature signals and converting the temperature signals into thermoelectromotive force signals using the Bezek effect of the thermocouples.

[0027] In some embodiments of the present specification, based on the Bezek effect between conductors or semiconductors, the temperature signal on the surface of the wafer is converted into a thermoelectric potential signal at both ends of the circuit structure during the temperature measurement process to achieve temperature measurement.

[0028] In some embodiments, the wafer temperature measurement system can use the transmission wire 4 to transmit the thermoelectromotive force signal to the temperature measurement wafer data acquisition instrument 6 .

[0029] In some embodiments, the vacuum penetration belt 5 may be located outside the transmission conductor 4 to protect the transmission conductor 4 , and the transmission conductor 4 and the vacuum penetration belt 5 constitute a temperature measurement signal transmission system.

[0030] In some embodiments of the present specification, the vacuum penetration belt 5 has the characteristics of high temperature resistance and corrosion resistance. The vacuum penetration belt 5 is used to protect the transmission wire 4 to ensure that the temperature measuring wafer can work in a high temperature environment.

[0031] In some embodiments, the temperature measuring wafer data acquisition instrument 6 receives the thermoelectromotive force signal of the temperature measuring signal transmission system to obtain the wafer surface temperature information; transmits the wafer surface temperature information to the receiver 7 via wireless signal transmission, and the receiver transmits the wafer surface temperature information to the host computer 8 through signal conversion.

[0032] In some embodiments, Figure 3 As shown, the key temperature measurement point is a groove structure, and the integrated thermocouple temperature measurement sensor 2 is respectively located in the groove and on the groove surface of the key temperature measurement point, and the groove in the key temperature measurement point and the integrated thermocouple temperature measurement sensor 2 on the groove surface are filled with silicon-based material; wherein, the filling height of the silicon-based material is consistent with the surface height of the temperature measurement wafer 1.

[0033] In some embodiments, the groove structure at the key temperature measurement point can be etched to obtain a groove structure with a special shape having a depth of 200 μm to 400 μm; wherein the groove cross-sectional shape can be a superposition of a circle and a rectangle.

[0034] In some embodiments, an on-chip and off-chip wafer temperature measurement device used in semiconductor manufacturing can embed an integrated thermocouple temperature sensor 2 in the groove to measure the internal temperature of the wafer; after embedding the sensor, the groove is filled with a silicon-based material that is the same as the wafer material, and the surface height after filling is level with the original wafer surface; the integrated thermocouple temperature sensor 2 is also arranged on this surface.

[0035] In some embodiments, an on-wafer and off-wafer temperature measurement device used in semiconductor manufacturing can measure the temperature of the wafer surface and the inside of the wafer, and calculate the contact thermal resistance generated by the contact between the thermocouple and the surface of the wafer to be measured; the temperature calculation result is adjusted using the contact thermal resistance to obtain the temperature calculation result after error correction.

[0036] In some embodiments of the present specification, this method can enable the temperature measuring wafer to have the ability to measure the temperature of the wafer surface and the inside of the wafer at key points at the same time; simultaneous temperature measurement on and under the wafer helps to calculate the contact thermal resistance between the sensor and the wafer surface, providing data support for the subsequent elimination of temperature measurement errors caused by contact thermal resistance, thereby improving temperature measurement accuracy.

[0037] In some embodiments, the on-chip and off-chip wafer temperature measuring device for semiconductor manufacturing can use temperature measuring software to detect the wafer surface temperature in real time, and record it according to the temperature-time curve and the wafer surface temperature distribution diagram. For example, the on-chip and off-chip wafer temperature measuring device for semiconductor manufacturing can place the temperature measuring wafer in the test environment, set the corresponding serial port, baud rate and open the serial port in the temperature measuring software, use the temperature measuring wafer data acquisition instrument 6 to collect the wafer surface temperature information and transmit it to the host computer 8, use the wafer surface temperature information displayed in the host computer 8 to control and correct the cold end potential, and use the wafer surface temperature information to draw a chart.

[0038] The present invention sets grooves on the surface of the wafer, arranges thermocouple temperature measuring sensors inside the grooves and the surface after filling of the wafer, so that the temperature measuring wafer has the ability to measure the temperature on and off the temperature measuring point; by measuring the temperature of the wafer surface and the inside of the wafer, the contact thermal resistance generated by the contact between the thermocouple wire and the surface of the wafer to be measured is quantitatively calculated, and the temperature measurement error caused by the contact thermal resistance is greatly reduced; by designing the groove cross section on the surface of the wafer as a superposition of a circle and a rectangle, it is beneficial to the subsequent filling of silicon-based materials and the increase of the contact length between the wire and the wafer, and the measurement error of the thermocouple sensor caused by the heat transfer of the wire is reduced.

Claims

1. An on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing, It is characterized in that include: A temperature measuring wafer (1), a transmission wire (4) connected to the temperature measuring wafer (1), a vacuum penetration belt (5) located outside the transmission wire (4), a temperature measuring wafer data acquisition device (6) connected to the transmission wire (4), a signal receiving device (7) remotely connected to the temperature measuring wafer data acquisition device (6), and a host computer (8); Conventional temperature measurement points and key temperature measurement points are arranged on the temperature measurement wafer (1); conventional thermocouple temperature measurement sensors (3) are arranged at the conventional temperature measurement points; integrated thermocouple temperature measurement sensors (2) are arranged on the surface and inside of the key temperature measurement points; grooves are arranged inside the key temperature measurement points, and the integrated thermocouple temperature measurement sensors (2) are arranged inside the key temperature measurement points through the grooves.

2. The on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing according to claim 1, It is characterized in that The inside of the groove at the key temperature measurement point and the space between the integrated thermocouple temperature measurement sensors (2) on the groove surface are filled with silicon-based materials; the groove has a depth of 200 μm to 400 μm and a shape that is a structure in which a circle and a rectangle are superimposed.

3. The on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing according to claim 2, It is characterized in that The filling height of the silicon-based material is consistent with the surface height of the temperature measuring wafer (1).

4. The on-chip and off-chip wafer temperature measurement device for semiconductor manufacturing according to claim 1, It is characterized in that The temperature measurement points of the temperature measurement wafer (1) are evenly distributed in a ring shape; wherein the temperature measurement points include conventional temperature measurement points and key temperature measurement points, and the conventional temperature measurement points and the key temperature measurement points are evenly distributed or regionally distributed.

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