WO2023155791A1

WO2023155791A1 - Wafer placement state detection method, and semiconductor process chamber and device

Info

Publication number: WO2023155791A1
Application number: PCT/CN2023/076074
Authority: WO
Inventors: 吕超; 柳朋亮
Original assignee: 北京北方华创微电子装备有限公司
Priority date: 2022-02-16
Filing date: 2023-02-15
Publication date: 2023-08-24
Also published as: CN114520172A; TWI822590B; TW202335125A

Abstract

The present invention provides a wafer placement state detection method for a semiconductor process chamber. The semiconductor process chamber comprises a chamber body and a bearing disc provided in the chamber body, the bearing disc is used for bearing a wafer and keeping the bearing disc at a set temperature value, and a temperature test member is provided in the bearing disc. The method comprises: placing a wafer on the bearing disc, and obtaining a minimum actual temperature test value tested by the temperature test member within a preset time period; determining whether the minimum actual temperature test value is lower than a preset temperature value; if yes, determining that a position of the wafer is normal, and continuing the process; and if not, determining that the position of the wafer is an anomaly. According to the method provided in the present invention, after the wafer is placed on the bearing disc, whether a drop amplitude of the tested actual temperature test value is large enough can be determined, and when the minimum actual temperature test value is not reduced to the preset temperature value, the position of the wafer is found to be an anomaly, so that the process is stopped, and the uniformity of a semiconductor process is ensured. The present invention also provides a semiconductor process chamber and a semiconductor process device.

Description

Wafer placed state detection method, semiconductor process chamber and equipment

technical field

The present invention relates to the field of semiconductor process equipment, in particular, to a method for detecting a placed state of a wafer, a semiconductor process chamber for realizing the method for detecting a placed state of a wafer, and a semiconductor process including the semiconductor process chamber equipment.

Background technique

Dry stripping refers to using plasma to remove the photoresist on the wafer. Compared with wet stripping, dry stripping has better effect and faster speed. In modern integrated circuit manufacturing, the wafer is usually placed on the carrier plate in the semiconductor process chamber, and then the process gas in the chamber is ionized to generate plasma, and the photoresist at a specific position on the wafer is treated by the plasma. Etching is performed. Wherein, the carrying plate plays a role of supporting and fixing the wafer, and controlling the temperature of the wafer during the process.

However, during the semiconductor process, the wafer sometimes overlaps when it is transferred to the carrier plate due to position deviation or other factors, which leads to uneven heating of the wafer by the carrier plate, which in turn causes the etching rate of the wafer to increase. Inconsistency affects process uniformity.

Contents of the invention

The present invention aims to provide a wafer placement state detection method, a semiconductor process chamber for realizing the wafer placement state detection method and a semiconductor process equipment including the semiconductor process chamber, the wafer placement state The detection method can ensure the stability of the position where the wafer is transferred to the susceptor.

In order to achieve the above object, as an aspect of the present invention, a method for detecting the placement state of a wafer is provided, which is applied to a semiconductor process chamber, and the semiconductor process chamber includes a cavity and a carrier plate arranged in the cavity, The carrying plate is used to carry the wafer, and the carrying plate is kept at a set temperature degree value, the carrying tray is provided with a temperature detection member for detecting the temperature near the carrying surface of the carrying tray, and the wafer placement state detection method includes:

placing the wafer on the carrying surface of the carrying tray, and obtaining the minimum actual temperature detection value among all the actual temperature detection values detected by the temperature detection member within a preset time;

Judging whether the minimum actual temperature detection value is lower than a preset temperature value, and the preset temperature value is lower than the preset temperature value; if yes, then determine that the wafer position is normal; if not, then determine that the wafer The circle position is abnormal.

Optionally, the wafer placement state detection method also includes a method for determining the preset temperature value, the method includes:

placing a wafer on the carrier plate, and keeping the wafer in a normal position;

Obtaining all the first temperature detection values detected by the temperature detection element, during the period from when the wafer is placed on the susceptor to when the temperature of the susceptor returns to the set temperature value Minimum first temperature detection value;

placing a wafer on the carrier plate, and keeping the wafer in an abnormal position;

Obtaining all the second temperature detection values detected by the temperature detection element, during the period from when the wafer is placed on the susceptor to when the temperature of the susceptor returns to the set temperature value Minimum second temperature detection value;

According to the minimum first temperature detection value and the minimum second temperature detection value, determine the preset temperature value, wherein the preset temperature value is between the minimum first temperature detection value and the minimum second temperature detection value Between the two temperature detection values.

Optionally, the determining the preset temperature value according to the minimum first temperature detection value and the minimum second temperature detection value specifically includes:

calculating a first temperature difference between the set temperature value and the minimum first temperature detection value, and a second temperature difference between the set temperature value and the minimum second temperature detection value;

Determine a preset temperature difference according to the first temperature difference and the second temperature difference, wherein, The magnitude of the preset temperature difference is between the first temperature difference and the second temperature difference;

A difference between the set temperature value and the preset temperature difference is calculated as the preset temperature value.

Optionally, the preset time is greater than the time it takes for the temperature of the susceptor to drop from the temperature before the wafer is placed on the susceptor to the minimum first temperature detection value and the susceptor The time it takes for the temperature of the wafer to drop to the minimum second temperature detection value from the temperature before the wafer is placed on the susceptor is less than the temperature of the susceptor since the wafer is placed on the susceptor The time taken for the previous temperature to return to the set temperature value.

Optionally, a heating assembly and at least one over-temperature detecting element are also arranged in the carrying tray, the heating assembly is used to heat the carrying tray, and the over-temperature detecting element is used to detect the temperature of the carrying tray. temperature, the wafer placement state detection method also includes:

When the temperature detection value of the over-temperature detection element is higher than a preset safety temperature value, the heating assembly is controlled to stop heating.

As a second aspect of the present invention, a semiconductor process chamber is provided, including a cavity and a carrier plate arranged in the cavity, the carrier plate is used to carry a wafer, and the carrier plate is connected to the The temperature of the wafer is kept at a set temperature value, and it is characterized in that a temperature detection member is arranged in the carrier plate for detecting the temperature near the carrier surface of the carrier plate, and the conductor process chamber also includes a control The device is used to implement the method for detecting the wafer placement state provided by the present invention.

Optionally, the temperature detection element is arranged at the center of the carrier plate.

Optionally, the temperature detecting element includes a thermocouple, and the distance between an end of the thermocouple facing the carrying plate and the carrying surface is 7 mm to 8 mm.

Optionally, a heating assembly and at least one over-temperature detecting element are also arranged in the carrying tray, the heating assembly is used to heat the carrying tray, and the over-temperature detecting element is used to detect the temperature of the carrying tray. Temperature: the control device is used to control the heating assembly to stop heating when the temperature detection value of the over-temperature detection element is higher than a preset safe temperature value.

Optionally, a plurality of over-temperature detection elements are arranged in the carrier plate, and the plurality of over-temperature detection elements are arranged at intervals along the circumference of the carrier plate.

As a third aspect of the present invention, a semiconductor process equipment is provided, the semiconductor process equipment includes the above-mentioned semiconductor process chamber provided by the present invention.

In the wafer placement state detection method, semiconductor process chamber and semiconductor process equipment provided by the present invention, after the wafer is placed on the carrying surface of the carrier plate, all the actual temperature detected by the temperature detection part within the preset time is acquired. The minimum actual temperature detection value in the temperature detection value can judge whether the detected actual temperature detection value drops from the set temperature value is large enough, that is, judge whether the minimum actual temperature detection value is lower than the preset temperature value, and When the minimum actual temperature detection value is lower than the preset temperature value, it is determined that the wafer position is normal, and when the minimum actual temperature detection value is not lower than the preset temperature value, it is determined that the wafer position is abnormal (for example, an edge overlap occurs), thereby Automatically identify whether the wafer position is normal, stop the semiconductor process in time when the wafer position is abnormal, avoid the semiconductor process chamber to continue the semiconductor process when the wafer position is abnormal, and ensure the semiconductor process on the wafer surface Uniformity and stability of the wafer transfer process, and reduces the risk of fragmentation and improves the safety of the semiconductor process.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention. In the attached picture:

1 is a schematic diagram of a situation in which a wafer falls on a carrier plate in a semiconductor process chamber provided by an embodiment of the present invention;

2 is a schematic diagram of another situation in which a wafer falls on a carrier plate in a semiconductor process chamber provided by an embodiment of the present invention;

3 is a schematic structural view of a carrier plate in a semiconductor process chamber provided by an embodiment of the present invention;

Fig. 4 is a top view of the carrying surface a region of the carrying tray in Fig. 3;

Fig. 5 is a schematic diagram of the change of the temperature detection value of the temperature detection member in the carrier tray under the conditions shown in Fig. 1 and Fig. 2;

6 is a schematic structural diagram of a control device in a semiconductor process chamber provided by an embodiment of the present invention;

FIG. 7 is a flowchart of a method for detecting a wafer placement state provided by an embodiment of the present invention.

Detailed ways

Specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

As shown in FIG. 1 and FIG. 2 , the surrounding of the carrying surface a of the carrying tray 100 usually has a limiting structure surrounding the carrying surface a. As shown in Figure 1, under normal circumstances, the transport component of the semiconductor process equipment can accurately place the wafer 10 in a position aligned with the carrying surface a, so that the wafer 10 can accurately fall into the area defined by the limiting structure , one side surface of the wafer 10 is completely in contact with the carrying surface a, so as to realize effective heat exchange with the carrying plate 100 .

However, as shown in FIG. 2 , in some cases, the transport assembly of the semiconductor process equipment may have a certain positional deviation when transporting the wafer 10 , which causes a side-over problem when the wafer 10 falls on the carrier plate 100 . That is, one edge of the wafer 10 rests on the limiting structure, so that the surface of the wafer 10 facing the carrying surface a cannot completely contact the carrying surface a, which not only affects the exchange between the wafer 10 and the carrying plate 100 Thermal efficiency reduces the controllability of the temperature of the wafer 10, affects the uniformity of the semiconductor process performed on the surface of the wafer 10, and may also cause the wafer 10 to further slide or even fall out of the carrier plate 100 in subsequent processes, resulting in debris accidents.

In order to solve the above technical problems, as an aspect of the present invention, a method for detecting the placement state of a wafer is provided, which is applied to a semiconductor process chamber. The semiconductor process chamber includes a cavity and a carrier plate 100 arranged in the cavity, carrying The tray 100 is used to carry the wafer, and maintain the tray 100 at a set temperature value TC1. As shown in FIG. 3 and FIG. 4 , a temperature detecting member 110 is provided in the carrier tray 100 for detecting the temperature of the carrier tray 100 close to the carrier surface a. The wafer placement state detection method is implemented by the control device of the semiconductor process chamber, as shown in FIG. 7, the wafer placement state detection method includes:

Step S1, place the wafer 10 on the carrying surface a of the carrying plate 100, and obtain the minimum actual temperature detection value among all the actual temperature detection values detected by the temperature detection member 110 within the preset time t2 (that is, the detected carrying Surface a has the lowest temperature);

Step S2, judging whether the minimum actual temperature detection value is lower than the preset temperature value TC4, and the preset temperature value TC4 is lower than the above-mentioned preset temperature value TC1; if so, it is determined that the wafer position is normal, and the process can be continued at this time; if If not, it is determined that the wafer position is abnormal, and the process needs to be stopped at this time.

The inventors of the present invention have found in experimental research that since the wafer 10 is at room temperature before being introduced into the semiconductor process chamber, there is a temperature difference between the carrier plate 100 kept at the set temperature value TC1, therefore, the wafer 10 is placed on the carrier plate After being placed on the bearing surface a of the tray 100 , there will be heat exchange with the tray 100 , so that the temperature of the tray 100 on the tray 100 will fluctuate to a certain extent. The heat exchange efficiency between the wafer 10 and the carrier plate 100 is related to the contact area between the two. Therefore, when the wafer 10 normally falls on the carrier surface a (all the wafers are placed on the carrier surface a), the carrier surface The fluctuation range of the temperature on a must be greater than the fluctuation range of the temperature on the carrying surface a when the wafer 10 overlaps (the wafer part is placed on the carrying surface a).

Specifically, the control device can control the heating power of the heating assembly in the carrier tray 100 through feedback regulation (specifically, proportional-integral-derivative (PID) regulation), that is, the control device can control the heating power of the heating assembly in the carrier tray 100 according to the temperature fed back by the temperature measuring element in the carrier tray 100 Adjust the heating power of the heating component in real time to keep the temperature value fed back by the temperature measuring element at the set temperature value TC1, and then keep the temperature of the susceptor 100 and the wafers carried on it at the set temperature value TC1.

Optionally, as shown in FIGS. 3 and 4 , a plurality of thimble holes 130 penetrating through the carrier 100 in the thickness direction are also formed in the carrier tray 100, which are used to cooperate with the ejector pin structure (such as a three-pin structure) to realize wafer lift. For example, three thimble holes 130 may be formed in the carrying tray 100. When the transport assembly is taken from the chamber, the three-needle structure below the carrying tray 100 rises upwards, and the three thimbles pass through the three thimble holes one by one. 130 and lift up the wafer on the carrier tray 100, so that the transfer assembly can lift the wafer from below and take the wafer away; The circle is placed on the three thimbles, and then the three-needle structure descends, so that the three thimbles pass through the three thimble holes respectively 130 is retracted below the carrier tray 100, and the wafer is placed on the carrier surface a (that is, corresponding to time t0 in FIG. 5 ).

As shown by the curve L1 in FIG. 5 , at time 0, the control device controls the three-needle structure to start to descend, so that the wafer 10 normally falls on the carrying surface a at time t0, and the surface on one side of the wafer 10 and the carrying plate 100 are in contact with each other. The surface a contacts and quickly absorbs the heat on the carrying plate 100, so that the temperature on the carrying surface a of the carrying plate 100 drops rapidly, and then the carrying plate 100 increases the heating power through proportional integral differential adjustment, so that the temperature of the carrying surface a returns to Set temperature value TC1.

As shown by the curve L2 in Figure 5, at time 0, the control device controls the three-needle structure to start to descend, so that when the wafer 10 falls on the carrier plate 100 at time t0 and the problem of overlapping occurs, the surface on one side of the wafer 10 is only partially In contact with the carrying surface a of the carrying plate 100, the rate at which it absorbs heat on the carrying plate 100 is lower than that corresponding to the curve L1, so the minimum temperature that can be reached by the carrying surface a on the curve L2 is higher than that on the carrying surface a on the curve L1 the lowest temperature. That is, the temperature adjustment capability of the carrier tray 100 remains unchanged, the temperature fluctuation range of the carrier surface a is larger when the wafer is normally dropped on the carrier surface a, and the temperature fluctuation range of the carrier surface a is smaller when the wafer overlaps, so that This feature can be used to identify whether the wafer position is normal.

In the wafer placing state detection method provided by the present invention, after placing the carrying surface a of the wafer on the carrying tray 100, the minimum value of all the actual temperature detection values detected by the temperature detection member 110 within a preset time is obtained. The actual temperature detection value can judge whether the detected actual temperature detection value drops from the set temperature value TC1 is large enough, that is, determine whether the minimum actual temperature detection value is lower than the preset temperature value TC4, and detect at the minimum actual temperature When the value is lower than the preset temperature value TC4, it is determined that the wafer position is normal. The position is abnormal (such as edge overlap), so as to automatically identify whether the wafer position is normal, and stop the semiconductor process in time when the wafer position is abnormal, avoiding the semiconductor process chamber to continue the semiconductor process when the wafer position is offset. The uniformity of the semiconductor process on the wafer surface and the stability of the transfer process are guaranteed, and the risk of debris is reduced, and the safety of the semiconductor process is improved.

It should be noted that the preset temperature value TC4 needs to be determined according to the fluctuation range of the temperature on the carrying surface a after the wafer normally falls on the carrying surface a. That is, the size of the preset temperature value TC4 is related to various factors such as the set temperature value TC1, the model of the susceptor 100, the material and size of the wafer, etc., considering the variability of the above-mentioned factors, in order to improve the method provided by the present invention. The adaptability of different semiconductor process chambers, as a preferred embodiment of the present invention, the wafer placement state detection method also includes a method for determining the preset temperature value TC4, the method includes:

Step S11, place the wafer 10 on the carrier plate 100, and make the wafer 10 in a normal position, that is, all the wafers 10 are placed on the carrier surface a, and obtain all the first temperature detected by the temperature detector 110. Among the temperature detection values, the minimum first temperature detection value TC2 is the period from when the wafer 10 is placed on the susceptor 100 to when the temperature of the susceptor 100 returns to the set temperature value TC1;

Step S12, place the wafer 10 on the carrier plate 100, and make the wafer 10 in a state of abnormal position, that is, the wafer 10 is partially placed on the carrier surface a (that is, the situation of overlapping the edge), and obtain the temperature detection part 110 Among all the detected second temperature detection values, the minimum second temperature detection value TC3 during the period from when the wafer 10 is placed on the susceptor 100 to when the temperature of the susceptor 100 returns to the set temperature value TC1;

Step S13, according to the minimum first temperature detection value TC2 and the minimum second temperature detection value TC3, determine the preset temperature value TC4, wherein the preset temperature value TC4 is between the minimum first temperature detection value TC2 and the minimum second temperature detection value Between TC3.

In the embodiment of the present invention, the control device first acquires the minimum first temperature detection value TC2 of the susceptor 100 when the wafer normally lands on the susceptor 100 in step S11, and then obtains the edge of the wafer in step S12, The minimum second temperature detection value TC3 of the susceptor 100 can determine a preset temperature value TC4 between the minimum first temperature detection value TC2 and the minimum second temperature detection value TC3, and use this as the wafer The basis for judging whether the film is uploaded normally. That is, after the wafer is placed on the susceptor 100, the temperature of the susceptor 100 drops below the preset temperature value TC4 (that is, the minimum first temperature detection value TC2 is lower than the preset temperature value TC4), then it can be determined that the The chip is normal; the temperature of the carrier plate 100 temperature is not lowered below the preset temperature value TC4 (that is, the minimum second temperature detection value TC3 is higher than or equal to the preset temperature value TC4), then it can be determined that the contact area between the wafer and the carrying surface a is too small, and the wafer Take the side.

As an optional implementation of the present invention, the preset temperature value TC4 is determined according to the minimum first temperature detection value TC2 and the minimum second temperature detection value TC3, specifically including:

Step S131, calculating the first temperature difference ΔTC1 between the set temperature value TC1 and the minimum first temperature detection value TC2, and the second temperature difference ΔTC2 between the set temperature value TC1 and the minimum second temperature detection value TC3 ;

Step S132: Determine the preset temperature difference ΔTC according to the first temperature difference ΔTC1 and the second temperature difference ΔTC2, wherein the preset temperature difference ΔTC is between the first temperature difference ΔTC1 and the second temperature difference Between ΔTC2;

Step S133 , calculating the difference between the set temperature value TC1 and the preset temperature difference value ΔTC as the preset temperature value TC4 .

Experimental verification by the inventor of the present invention shows that in the existing dry deglue machine, after the wafer normally falls on the carrying surface a, the maximum fluctuation range of the temperature detection value of the temperature detection member 110 set in the carrying tray 100 (i.e. ΔTC1) is about 3°C; when the wafers overlap, the maximum fluctuation range (ie ΔTC2) of the temperature detection value of the temperature detection element 110 is about 0.5°C. That is, the preset temperature difference ΔTC can be set to a certain value between 0.5°C and 3°C.

As an optional implementation of the present invention, the preset temperature difference ΔTC can take a value of 2°C, that is, the preset temperature value TC4 is 2°C lower than the set temperature value TC1, such as placing the wafer 10 on a carrier After the tray 100 is placed on the tray 100 , if the temperature of the tray 100 drops by more than 2° C., it can be considered that the bottom surface of the wafer 10 is in full contact with the carrying surface a of the tray 100 , and the position of the wafer 10 is normal.

The embodiment of the present invention does not specifically limit the length of the preset time t2, as long as it can ensure that the peak value of the fluctuation of the temperature detection value of the temperature detection element 110 falls within the preset time t2. For example, as an optional implementation of the present invention, the length of time elapsed when the temperature detection value of the temperature detection member 110 reaches the lowest point after the wafer is placed can be recorded, and the preset time t2 can be determined with reference to the time length. Specifically, Qu The time corresponding to the lowest point of the line L1 and the curve L2 is usually not much different (that is, the time t1 in Figure 5). When the preset time t2 is selected, the preset time t2 is greater than the t1 corresponding to the lowest point of all the previously collected temperature curves. That's it. In addition, since it usually takes a certain amount of time to restore the carrying tray 100 to the set temperature value TC1 through feedback adjustment, in order to improve detection efficiency, the preset time t2 is preferably shorter than the time for the carrying surface a to return to the set temperature value TC1.

That is, the preset time t2 is greater than the time it takes for the temperature of the susceptor 100 to drop from the temperature before the wafer is placed on the susceptor 100 to the minimum first temperature detection value TC2 and the temperature of the susceptor 100 from the time the wafer is placed on the susceptor 100 The time taken for the disk 100 to drop to the minimum second temperature detection value TC3 before (that is, greater than the time t1 of each collected curve), and less than the temperature of the susceptor 100 recovers from the temperature before the wafer is placed on the susceptor 100 to the set value. The time it takes to set the temperature value TC1.

In order to improve the safety of the semiconductor process, as a preferred embodiment of the present invention, as shown in FIG. Heating is carried out, and the over-temperature detection part 120 is used to detect the temperature of the susceptor 100, and the method for detecting the placement state of the wafer also includes:

When the detected temperature value of the over-temperature detecting element 120 is higher than the preset safe temperature value, the heating component is controlled to stop heating.

In the embodiment of the present invention, the control device monitors the temperature detection value of the over-temperature detection part 120 in real time. High, actively control the heating assembly to stop heating, so as to avoid problems such as cracking of the carrier plate 100 and protrusion of the carrier surface a caused by the high temperature of the carrier plate 100, and protect the carrier plate 100 and the corresponding internal structures.

As an optional implementation of the present invention, the preset safe temperature value may be set between the normal operating temperature of the carrier tray 100 and the upper limit of temperature resistance. For example, the upper limit of the heating temperature of the carrier tray 100 is about 350°C, and its working environment is 200°C-275°C, so the preset safe temperature value can be set between 275°C and 350°C. For example, the preset safe temperature value may be 320°C.

As a preferred embodiment of the present invention, the temperature detection element 110 is multiplexed as a temperature measuring element for the control device to feedback adjust (PID regulation) the heating power of the heating assembly, that is, the control device is used to obtain the temperature detection value of the temperature detection element 110 in real time , and adjust (PID adjustment) the heating power of the heating assembly according to the difference between the temperature detection value and the set temperature value TC1, so as to keep the temperature detection value of the temperature detection part 110 at the set temperature value TC1, and then load The temperature of the tray 100 and the wafer 10 carried thereon is maintained at a set temperature value TC1.

For the convenience of technicians to understand, the following provides a detailed process for the control device to confirm the preset temperature value TC4 when the preset temperature value TC1 is 275°C:

After the control device receives the set temperature value TC1 as 275°C, it adjusts the heating power in the carrier tray 100 according to the temperature detection value of the temperature detection part 110 in real time, so as to keep the temperature detection value of the temperature detection part 110 at 275°C .

Before processing the wafer, the control device performs a process test. First, control the transfer assembly to transfer the wafer to the three-pin structure of the carrier tray 100, and then control the three-pin structure to descend, so that all the wafers are placed on the carrier surface a of the carrier tray 100 (that is, the wafer is normally transferred to the carrier tray 100 circle), and obtain the temperature detection value of the temperature detection part 110 in real time, and obtain the temperature curve L1 of the carrier plate 100 corresponding to the normal situation. Analysis of the curve L1 shows that the first temperature difference ΔTC1 between the minimum first temperature detection value TC2 and the set temperature value TC1 when the temperature of the carrier plate 100 fluctuates is about 3°C, falling from the three-pin structure to the temperature detection part The time t1 elapsed when the temperature detection value of 110 drops to the lowest point (TC2) is about 13s;

Then, (after taking off the previous wafer 10 ) control the transfer assembly to transfer the wafer to the carrier tray 100, and then control the three-pin structure to descend, so that the wafer part is placed on the carrier surface a of the carrier tray 100 (i.e., the wafer Overlapping), the temperature detection value of the temperature detection part 110 is also obtained in real time, and the temperature curve L2 of the carrier plate 100 corresponding to the overlapping situation is obtained. Analysis of the curve L2 shows that the second temperature difference ΔTC2 between the minimum second temperature detection value TC3 and the set temperature value TC1 when the temperature of the carrier plate 100 fluctuates is about 0.5°C (the time t1 corresponding to the lowest point is also about 13s).

Finally, the control device can determine the value ranges of the preset temperature value TC4 and the preset time t2 according to the results of the two process tests, specifically:

From the values of the first temperature difference ΔTC1 and the second temperature difference ΔTC2 , it can be known that the value range of the temperature difference ΔTC is ΔTC2<ΔTC<ΔTC1, ie, 0.5°C<ΔTC<3°C. The value for ΔTC is 2°C. Then the preset temperature value TC4=TC1-ΔTC=273°C can be obtained.

From the value of t1, it can be seen that the value range of the preset time t2 is t2>t1, that is, t2>13s. The value of the preset time t2 is taken, so that the preset time t2=20s.

Then the control device can write the temperature difference ΔTC (preset temperature value TC4) into the process recipe corresponding to the current wafer, and write the preset time t2 into the software configuration item (setup).

Then in the semiconductor process, the control device can judge according to the set value when transferring the film. If the temperature detection value of the temperature detection part 110 does not drop below 273°C within 20 seconds after the three-needle structure is lowered, the judgment is made. Wafer overlap (that is, the wafer position is abnormal).

In order to improve the security of the semiconductor process and the troubleshooting efficiency of the semiconductor process production line, as a preferred embodiment of the present invention, the method also includes throwing an alarm (for example, a control bee The buzzer rings, the indicator light flashes, and the corresponding alarm window pops up on the interface, etc.).

As a second aspect of the present invention, a semiconductor process chamber is provided, including a cavity and a carrier plate 100 disposed in the cavity, the carrier plate 100 is used to carry a wafer, and the temperature of the carrier plate 100 and the wafer Keep at the set temperature value TC1. The carrier tray 100 is provided with a temperature detection element 110 for detecting the temperature of the carrier tray 100 close to the carrier surface a, and the conductor process chamber also includes a control device for implementing the wafer placement state detection method provided by the embodiment of the present invention .

In the semiconductor process chamber provided by the present invention, after the wafer is placed on the carrying surface a of the carrying tray 100, the minimum actual temperature detection value among all the actual temperature detection values detected by the temperature detection part within the preset time is obtained. value, it can be judged whether the detected actual temperature detection value drops from the set temperature value is large enough, that is, to judge whether the minimum actual temperature detection value is lower than the preset temperature value, and when the minimum actual temperature detection value is lower than the preset temperature value In the case of the temperature value, it is judged that the wafer position is normal. When the minimum actual temperature detection value is not lower than the preset temperature value, it is determined that the wafer position is abnormal (such as edge overlap), so as to realize automatic identification of whether the wafer position is normal, and stop the semiconductor process in time when the wafer position is abnormal, to avoid It ensures that the semiconductor process chamber can continue the semiconductor process when the wafer position is abnormal, ensures the uniformity of the semiconductor process on the wafer surface and the stability of the transfer process, reduces the risk of debris, and improves the reliability of the semiconductor process. safety.

As an optional implementation manner of the present invention, a heating component is further disposed in the carrier tray 100 for heating the carrier tray 100 . Optionally, as shown in FIG. 3 , the heating assembly includes a heating wire 150 buried inside the carrier plate 100. The heating wire 150 can generate heat based on the principle of electric heating after being connected to the power supply, thereby heating the carrier plate 100 and the load on it. The wafer is heated. Optionally, the semiconductor process chamber provided by the present invention can be used for a dry debonding process.

In order to ensure the recognition accuracy of the control device to the edge of the wafer, as a preferred embodiment of the present invention, as shown in FIG. The projection on the carrier surface a of the disc 100 coincides with the axis of the carrier disc 100 .

When the position of the wafer is shifted and there is an edge overlap problem, there is randomness in the orientation of the contact between the edge of the wafer and the bearing surface a, and the contact position between the edge of the wafer and the bearing surface a changes with the offset of the wafer position Therefore, in the embodiment of the present invention, the temperature detection element 110 is arranged in the center of the carrier plate 100, so that no matter which side of the wafer is in contact with the carrier surface a when the wafer overlaps, the detection result of the temperature detection element 110 will not be affected. There is a difference from the normal situation, thereby ensuring the identification accuracy of the wafer edge problem.

As an optional implementation manner of the present invention, the temperature detection element 110 may include a thermocouple. In order to ensure the temperature detection effect of the temperature detection member 110 on the carrier plate 100 and avoid its influence on the flatness of the carrier surface a and the uniformity of the wafer temperature, as a preferred embodiment of the present invention, as shown in FIG. 3 , the thermocouple The distance d between one end facing the carrying tray 100 and the carrying surface a is 7 mm to 8 mm. Optionally, the distance d between the end of the thermocouple facing the carrier plate 100 and the carrier surface a is 7.5 mm.

In order to ensure the stability of the thermocouple fixed in the carrier plate 100, preferably, the thermocouple is a type K The armored thermocouple is screwed into the threaded hole at the bottom center of the carrier plate 100 through the threads on the outer surface of the thermocouple, so as to realize the fast connection with the carrier plate 100 .

Optionally, the outer diameter of the thermocouple of the temperature detecting element 110 is about 3 mm, the response speed is 1.2 s, and the temperature measurement accuracy is Class I.

In order to improve the safety of the semiconductor process, as a preferred embodiment of the present invention, as shown in FIG. temperature. The control device is used to control the heating component to stop heating when the detected temperature value of the over-temperature detecting element 120 is higher than a preset safe temperature value.

In the embodiment of the present invention, the control device monitors the temperature detection value of the over-temperature detection part 120 in real time. High, actively control the heating component to stop heating, so as to avoid problems such as cracking of the carrier plate 100 and protrusion of the carrier surface a caused by the high temperature of the carrier plate 100, and protect the carrier plate 100 and its internal corresponding structures.

As a preferred embodiment of the present invention, the over-temperature detection element 120 includes a thermocouple, which is embedded and installed near the heating wire 150 , and located between the center and the edge of the carrier plate 100 . In the semiconductor process, the heat generated by the heating wire 150 is conducted outward through the carrier plate 100, so that the temperature of the entire carrier plate 100 and the wafer 10 carried on it is kept at a set temperature value TC1, and the temperature inside the carrier plate has a gradient distribution. That is, the temperature gradually decreases along the direction away from the heating wire 150. Therefore, in order to ensure that the control device detects the abnormal situation that the temperature of the carrier plate 100 is too high in time, the over-temperature detection part 120 is preferably arranged as close as possible to the heating wire 150, so that the over-temperature detection part 120 It can detect the temperature near the heating wire 150 in real time, so that the control device can detect abnormalities faster when the temperature of the heating wire 150 exceeds the preset safe temperature value, thereby better avoiding the overheating of the carrier plate 100 and causing it to break and fail. Problems such as surface a protrusion, etc., protect the carrier plate 100 and its internal corresponding structures.

Preferably, the position of the over-temperature detection part 120 along the thickness direction of the carrier plate 100 corresponds to the heating wire 150 (that is, the over-temperature detection part 120 and the heating wire 150 are located on the same horizontal plane), so as to improve the temperature of the carrier plate 100. When the temperature is too high, the control device recognizes the efficiency of the abnormal problem through the over-temperature detection part 120 .

Optionally, the tops of the heating wire 150 and the over-temperature detection element 120 are about 17.5 mm away from the carrying surface a of the carrying tray 100 . Optionally, the outer diameter of the thermocouple in the over-temperature detection element 120 is about 3mm.

In order to further improve the safety of the semiconductor process, as a preferred embodiment of the present invention, a plurality of over-temperature detection elements 120 are arranged in the carrier plate 100, and the plurality of over-temperature detection elements 120 are arranged at intervals along the circumference of the carrier plate 100, Therefore, the temperature in all directions of the carrier tray 100 can be detected in real time, and the alarm sensitivity can be improved.

As a preferred embodiment of the present invention, as shown in FIG. 4 , an air guide groove 140 is also formed on the carrying surface a of the carrying tray 100 for guiding the gas between the wafer and the carrying surface a to be uniformly discharged along the circumferential direction. , to ensure the stability of the wafer position.

Optionally, as shown in FIG. 4 , the air guide groove 140 includes a plurality of radiating grooves 141, each radiating groove 141 extends radially from the center of the bearing surface a, and the plurality of radiating grooves 141 are distributed along the circumferential direction for guiding Gas is discharged radially.

Preferably, as shown in FIG. 4 , the air guide groove 140 further includes at least one annular groove 142, the annular groove 142 extends circumferentially around the axis of the carrier plate 100, and intersects with multiple (all) radiation grooves 141 for improving The pressure uniformity of the gas along the circumferential direction can prevent the horizontal position of the wafer from shifting due to the unevenness of the circumferential air flow when the gas between the wafer and the carrying surface a is discharged when the wafer falls, thereby further improving the stability of the wafer position sex.

As an optional implementation of the present invention, as shown in FIG. 3 , the temperature detection part 110, the over-temperature detection part 120 and the heating assembly are all connected to the circuit outside the chamber through a high-temperature resistant flexible wire 170, and the high-temperature resistant flexible wire 170 The surface layer has a shielding layer.

In order to prolong the service life of the high-temperature-resistant flexible wire 170, as an optional embodiment of the present invention, as shown in FIG. The bottom wall of the process chamber is fixedly connected, and the inside of the insulating sleeve 160 communicates with the outside of the cavity through the through hole on the bottom wall of the cavity, and the high temperature resistant flexible wire 170 passes through the insulating sleeve 160 and the cavity. External circuits (eg, power supply, control devices, etc.) are connected.

As an optional implementation of the present invention, as shown in FIG. 6, the control device (outside the dotted line frame is the structure of the control device, and inside the dotted line frame is the structure arranged in the carrier plate 100) includes a temperature controller and a solid state relay. The controller is used to receive the temperature detection value of the temperature detection part 110 in the carrier tray 100, and according to the difference between the temperature detection value and the set temperature value TC1, adjust the final output power of the power supply (Power) to the heating component in real time through the solid state relay , and further realize the feedback adjustment (PID adjustment) of the temperature of the susceptor 100, and keep the temperature of the susceptor 100 and the wafers carried thereon at the set temperature value TC1.

In the case where an over-temperature detection element 120 is also provided on the carrier plate 100, as an optional implementation of the present invention, as shown in FIG. 6, the control device further includes a temperature control module and a The AC contactor, the temperature control module is used to cut off the AC contactor when the temperature detection value of the over-temperature detection part 120 exceeds the preset safe temperature value (for example, 320°C) according to the judgment logic of the temperature control module, so that the power supply cannot Loaded on the heating assembly, so as to protect the structure in the carrier tray 100.

As a third aspect of the present invention, a semiconductor process equipment is provided, and the semiconductor process equipment includes the semiconductor process chamber provided by the embodiment of the present invention. Optionally, the semiconductor process equipment further includes a transport component for transporting the wafer to the susceptor 100 in the semiconductor process chamber (specifically, transporting the wafer to the raised three-needle structure of the susceptor 100 ).

In the semiconductor process equipment provided by the present invention, the control device of the semiconductor process chamber can obtain all the actual temperature detections detected by the temperature detection part 110 within a preset time after the wafer is placed on the carrying surface of the carrying plate 100. The minimum actual temperature detection value in the value can judge whether the detected actual temperature detection value drops from the set temperature value TC1 is large enough, that is, judge whether the minimum actual temperature detection value is lower than the preset temperature value TC4, and in When the minimum actual temperature detection value is lower than the preset temperature value TC4, it is determined that the wafer position is normal, and when the minimum actual temperature detection value is not lower than the preset temperature value TC4 (that is, the temperature drop of the bearing surface a is too small) , determine the found wafer bit Abnormal setting, stop the semiconductor process in time when the wafer position is abnormal, avoid the semiconductor process chamber to continue the semiconductor process when the wafer position is abnormal, and ensure the uniformity of the semiconductor process on the wafer surface and the transfer process stability, and reduces the risk of fragmentation, improving the safety of semiconductor processes.

It can be understood that, the above embodiments are only exemplary embodiments adopted for illustrating the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

A wafer placement state detection method, applied to a semiconductor process chamber, the semiconductor process chamber includes a cavity and a carrier plate arranged in the cavity, the carrier plate is used to carry the wafer, and the The carrying plate is kept at a set temperature value, and it is characterized in that a temperature detection member is arranged in the carrying plate for detecting the temperature of the carrying plate close to the carrying surface, and the wafer placement state detection method includes:

placing the wafer on the carrying surface of the carrying tray, and obtaining the minimum actual temperature detection value among all the actual temperature detection values detected by the temperature detection member within a preset time;

Judging whether the minimum actual temperature detection value is lower than a preset temperature value, and the preset temperature value is lower than the preset temperature value; if yes, then determine that the wafer position is normal; if not, then determine that the wafer The circle position is abnormal.
The wafer placement state detection method according to claim 1, wherein the wafer placement state detection method also includes a method for determining the preset temperature value, the method comprising:

placing a wafer on the carrier plate, and keeping the wafer in a normal position;

Obtaining all the first temperature detection values detected by the temperature detection element, during the period from when the wafer is placed on the susceptor to when the temperature of the susceptor returns to the set temperature value Minimum first temperature detection value;

placing a wafer on the carrier plate, and keeping the wafer in an abnormal position;

Obtaining all the second temperature detection values detected by the temperature detection element, during the period from when the wafer is placed on the susceptor to when the temperature of the susceptor returns to the set temperature value Minimum second temperature detection value;

According to the minimum first temperature detection value and the minimum second temperature detection value, determine the preset temperature value, wherein the preset temperature value is between the minimum first temperature detection value and the minimum second temperature detection value Between the two temperature detection values.
The wafer placing state detection method according to claim 2, wherein said determining said preset temperature value according to said minimum first temperature detection value and said minimum second temperature detection value specifically comprises:

calculating a first temperature difference between the set temperature value and the minimum first temperature detection value, and a second temperature difference between the set temperature value and the minimum second temperature detection value;

Determine a preset temperature difference according to the first temperature difference and the second temperature difference, wherein the preset temperature difference is between the first temperature difference and the second temperature between the difference;

A difference between the set temperature value and the preset temperature difference is calculated as the preset temperature value.
The wafer placing state detection method according to claim 2 or 3, wherein the preset time is longer than the temperature of the susceptor dropping from the temperature before the wafer is placed on the susceptor to the The time it takes for the minimum first temperature detection value and the time it takes for the temperature of the susceptor to drop from the temperature before the wafer is placed on the susceptor to the minimum second temperature detection value are less than the The time taken for the temperature of the susceptor to recover from the temperature before the wafer is placed on the susceptor to the set temperature value.
The wafer placement state detection method according to any one of claims 1 to 3, wherein a heating assembly and at least one over-temperature detection piece are also arranged in the carrying tray, and the heating assembly is used to monitor the The carrying plate is heated, the over-temperature detection part is used to detect the temperature of the carrying plate, and the wafer placing state detection method further includes:

When the temperature detection value of the over-temperature detection element is higher than a preset safety temperature value, the heating assembly is controlled to stop heating.
A semiconductor process chamber, comprising a cavity and a carrier plate arranged in the cavity, the carrier plate is used to carry a wafer, and keep the temperature of the carrier plate and the wafer at a set temperature value, it is characterized in that a temperature detection piece is set in the carrier plate for detecting the temperature of the carrier plate Close to the temperature of the carrying surface, the conductor processing chamber further includes a control device for implementing the wafer placement state detection method according to any one of claims 1 to 5.
The semiconductor process chamber according to claim 6, wherein the temperature detection element is arranged at the center of the carrier plate.
The semiconductor process chamber according to claim 7, wherein the temperature detection element comprises a thermocouple, and the distance between the end of the thermocouple facing the carrier plate and the carrier surface is 7 mm to 8 mm .
The semiconductor process chamber according to any one of claims 6 to 8, wherein a heating assembly and at least one over-temperature detection element are also arranged in the carrier tray, and the heating assembly is used to The plate is heated, and the over-temperature detection part is used to detect the temperature of the carrying plate; the control device is used to control the The heating element stops heating.
The semiconductor process chamber according to claim 9, wherein a plurality of over-temperature detection elements are arranged in the carrier plate, and the plurality of over-temperature detection elements are arranged at intervals along the circumference of the carrier plate .
A semiconductor process equipment, characterized in that the semiconductor process equipment comprises the semiconductor process chamber according to any one of claims 6-10.