CN-121985783-A - Tray, semiconductor process chamber and control method

Abstract

The application discloses a tray, a semiconductor process chamber and a control method, wherein the tray is used for fixing a wafer in the semiconductor process chamber and comprises an adsorption area, the surface of the adsorption area is a concave surface and is provided with a plurality of ventilation holes, the adsorption area is provided with an air flow channel communicated with the ventilation holes, the curvature of the concave surface meets the condition that the warpage of the wafer does not exceed the allowable maximum warpage when the wafer is attached to the adsorption area, an annular transition area is arranged around the adsorption area and is used for supporting the wafer before the wafer is adsorbed and fixed, and the ventilation holes and the air flow channel are used for introducing circulating gas when the wafer is borne on an annular bearing part so as to adsorb and fix the wafer. The application can prevent the wafer from sliding relative to the tray, avoid the wafer from being scratched, and can adjust the flow rate of the circulating gas in real time so as to keep the adsorption pressure borne by the wafer stable.

Inventors

• WANG XIAOFANG
• HUANG RUI
• ZHAO WANHUI
• CHEN XIAO
• ZHANG TAO
• GAO XIONG
• LIU KAI

Assignees

• 北京北方华创微电子装备有限公司

Dates

Publication Date

20260505

Application Date

20260203

Claims (15)

1. 1. A tray for holding wafers in a semiconductor processing chamber, the tray comprising: An adsorption zone, the surface of which is a concave surface with a preset curvature and is provided with a plurality of vent holes, and the adsorption zone is provided with an airflow channel communicated with the vent holes; the annular transition zone is arranged around the adsorption zone and is used for supporting the wafer before the wafer is adsorbed and fixed; the vent hole and the airflow channel are used for introducing circulating gas when the wafer is loaded on the annular bearing part so as to adsorb and fix the wafer.
2. 2. The tray of claim 1, wherein the plurality of vent holes comprises at least one first through hole disposed proximate the annular transition zone, a second through hole disposed at a center of the suction zone, and a plurality of blind holes; the air flow channel is communicated with the first through hole, the second through hole and the blind holes; The first through hole and the second through hole penetrate through the adsorption area, wherein one through hole is used for introducing the circulating gas into the gas flow channel, and the other through hole is used for discharging the circulating gas from the gas flow channel.
3. 3. The tray according to claim 2, wherein the air flow passage includes a plurality of annular grooves provided inside the suction area and centered on the second through hole, and a plurality of radial grooves; The annular grooves are sequentially arranged at intervals in a concentric nested manner, the radial grooves are arranged between two adjacent annular grooves, and the radial grooves are arranged between the second through hole and the innermost annular groove; The first through hole is communicated with the outermost annular groove; The blind holes are arranged on circumferences with different radiuses, corresponding to the annular grooves, on the surface of the adsorption area one by one and are communicated with the corresponding annular grooves.
4. 4. A pallet as claimed in claim 3 wherein the first through hole is located on the same circumference as the blind hole of the outermost ring and passes through the annular groove of the outermost ring; The plurality of radial grooves includes: The plurality of first radial grooves are arranged in the adsorption zone and are used for communicating two adjacent annular grooves in the secondary outer ring; the second radial grooves are arranged on the surface of the adsorption area and are used for connecting the first through holes with blind holes of the secondary outer ring; And the at least one third radial groove is arranged on the surface of the adsorption area and is used for connecting the second through hole and the blind hole of the innermost ring.
5. 5. The tray according to claim 4, wherein a plurality of the first through holes and the blind holes are provided on the circumference of the outermost ring, and the plurality of the first through holes and the blind holes are uniformly spaced on the circumference of the outermost ring.
6. 6. The pallet of claim 4, wherein the first radial grooves of each turn are provided in plurality and uniformly disposed in the circumferential direction.
7. 7. The tray of claim 6, wherein the first radial grooves of adjacent turns are evenly staggered in the radial direction.
8. 8. The pallet of claim 6, wherein the number of first radial grooves in each turn is the same and corresponds one to one; All corresponding first radial grooves in odd circles are arranged on a first radius of the adsorption area along the radial direction of the adsorption area, and all corresponding first radial grooves in even circles are arranged on a second radius of the adsorption area; The second radial groove and the third radial groove are disposed on the first radius or the second radius at the same time.
9. 9. The tray according to any one of claims 1to 8, wherein the adsorption area is an arc surface, and a radius of curvature of the arc surface is 50m or more; The annular transition zone is an inclined plane which is inclined downwards from outside to inside, and the inclination angle is smaller than or equal to 3 degrees.
10. 10. A semiconductor process chamber comprising a chamber body, a support device, and the tray of any one of claims 1-9; The supporting device is arranged in the chamber body, and the tray is arranged on the supporting device; And an air inlet channel and an air outlet channel for supplying the circulating gas to the adsorption area are arranged in the supporting device.
11. 11. The semiconductor process chamber of claim 10, wherein the support means comprises: the rotary shaft is connected with one surface of the adsorption area, which is away from the concave surface, the center of the rotary shaft is provided with the exhaust channel, and the exhaust channel axially penetrates through the rotary shaft; At least two first support rods extending from the outer side of the rotating shaft to the surface of the adsorption zone, which faces away from the concave surface, wherein each first support rod comprises a hollow part; the rotary shaft is further provided with an annular groove, and the annular groove extends from one end of the rotary shaft away from the adsorption zone to be communicated with the hollow part so as to form the air inlet channel.
12. 12. The semiconductor process chamber of claim 10, wherein the top wall of the chamber body is a transparent member; the semiconductor process chamber further comprises: the distance meter is arranged right above the chamber body, and the projection on the adsorption area is positioned at the annular transition area and used for detecting the current warping degree of the wafer through the top wall of the chamber body; and the controller is used for adjusting the flow rate of the circulating gas so as to adjust the current warping degree to the target warping degree.
13. 13. The semiconductor processing chamber of claim 12, the semiconductor process chamber is characterized by further comprising: the heating component is arranged above the chamber body and is used for heating the wafer; the first thermometer is arranged above the chamber body and is used for measuring the temperature of the central area of the wafer; the second thermometer is arranged above the chamber body and is used for measuring the temperature of the inner edge area of the annular transition area; The first heater is arranged above the chamber body, and the projection of the first heater on the tray is close to the inner edge area of the annular transition area, and is used for adjusting heating power to calibrate the temperature of the inner edge area when the temperature of the inner edge area deviates from the central temperature by more than a preset threshold value; The third thermometer is arranged above the chamber body and is used for measuring the temperature of the outer edge area of the annular transition area; The second heater is arranged above the chamber body, and the projection of the second heater on the tray is close to the outer edge area of the annular transition area, and is used for adjusting heating power to calibrate the temperature of the outer edge area when the temperature of the outer edge area deviates from the central temperature by more than a preset threshold value.
14. 14. A semiconductor processing apparatus includes The semiconductor process chamber of any one of claims 10-13; an intake and/or exhaust valve in communication with the airflow passage, and The controller is connected with the air inlet valve and the air outlet valve and is used for acquiring the current chamber pressure and the current adsorption pressure of the process semiconductor process chamber; If the difference of the current chamber pressure minus the current adsorption pressure is smaller than a preset minimum pressure difference, increasing the opening of the air inlet valve or the air outlet valve to increase the current adsorption pressure; And if the difference is greater than a preset maximum pressure difference, reducing the opening of the air inlet valve or the air outlet valve to reduce the current adsorption pressure until the difference is greater than or equal to the minimum pressure difference and less than or equal to the maximum pressure difference.
15. 15. The semiconductor processing apparatus of claim 14, further comprising: the heating component is arranged above the chamber body and is used for heating the wafer; the first thermometer is arranged above the chamber body and is used for measuring the temperature of the central area of the wafer; the second thermometer is arranged above the chamber body and is used for measuring the temperature of the inner edge area of the annular transition area; The first heater is arranged above the chamber body, and the projection of the first heater on the tray is close to the inner edge area of the annular transition area, and is used for adjusting heating power to calibrate the temperature of the inner edge area when the temperature of the inner edge area deviates from the central temperature by more than a preset threshold value; The third thermometer is arranged above the chamber body and is used for measuring the temperature of the outer edge area of the annular transition area; The second heater is arranged above the chamber body, and the projection of the second heater on the tray is close to the outer edge area of the annular transition area, and is used for adjusting heating power to calibrate the temperature of the outer edge area when the temperature of the outer edge area deviates from the central temperature by more than a preset threshold value; the controller is further configured to: Obtaining target process parameters, wherein the target process parameters comprise a first target temperature of the center of the wafer, a second target temperature of the position, corresponding to the inner edge region of the annular transition region, of the wafer, a third target temperature of the position, corresponding to the outer edge region of the annular transition region, of the wafer, and target process time; acquiring the center temperature of the wafer measured by the first thermometer, the first temperature of the position, corresponding to the inner edge area, of the wafer measured by the second thermometer and the annular transition area, and the second temperature of the position, corresponding to the outer edge area, of the wafer measured by the third thermometer and the annular transition area; adjusting the heating power of the heating assembly according to the central temperature and the first target temperature, adjusting the heating power of the first heater according to the first temperature and the second target temperature, and adjusting the heating power of the second heater according to the second temperature and the third target temperature; and acquiring the current process time which is already performed until the process time which is already performed is equal to the target process time.

Description

Tray, semiconductor process chamber and control method Technical Field The application relates to the technical field of semiconductors, in particular to a tray, a semiconductor process chamber and a control method. Background Epitaxial growth is a process for growing a single crystal thin film on a single crystal silicon substrate, and comprises the following main steps: (1) Placing a wafer on a tray within a semiconductor process chamber; (2) The tray drives wafer to start rotating and simultaneously heats up and controls pressure to meet the target requirement; (3) Introducing process gas (such as DCS, siH 4、GeH4 and the like) to carry out epitaxial reaction; (4) The epitaxy is completed to stop rotation, wafer is transferred out through a gate valve by using a tray, and a subsequent process is performed. Referring to fig. 1 and 2, fig. 1 is a schematic cross-sectional structure of a conventional tray, and fig. 2 is a schematic top view of the tray of fig. 1, including an inner region 11a and a transition region 12a, wherein the transition region 12a is an inclined surface and has a certain roughness to increase the friction between the tray and the wafer W, so as to prevent the wafer W from moving relative to the tray under the conditions of transformation and rotation in the epitaxial process. One surface of the tray facing the wafer W is provided with one or more grooves 13a extending from the center to the edge, and when the wafer W is placed on the tray, gas at the bottom of the wafer W can be discharged through the grooves 13a, so that the wafer W is prevented from sliding easily when placed on the tray. However, the roughness design of the transition zone 12a of the tray is susceptible to scratching of the wafer W. Disclosure of Invention The application provides a tray, a semiconductor process chamber and a control method, which can solve the problem that the existing design of the roughness of the transition area of the tray is easy to cause wafer scratch. To solve the above technical problem, in a first aspect, an embodiment of the present application provides a tray for fixing a wafer in a semiconductor process chamber, the tray including: An adsorption zone, the surface of which is a concave surface with a preset curvature and is provided with a plurality of vent holes, and the adsorption zone is provided with an airflow channel communicated with the vent holes; the annular transition zone is arranged around the adsorption zone and is used for supporting the wafer before the wafer is adsorbed and fixed; the vent hole and the airflow channel are used for introducing circulating gas when the wafer is loaded on the annular bearing part so as to adsorb and fix the wafer. Optionally, the plurality of ventilation holes include at least one first through hole disposed near the annular transition zone, a second through hole disposed at a center of the adsorption zone, and a plurality of blind holes; the air flow channel is communicated with the first through hole, the second through hole and the blind holes; The first through hole and the second through hole penetrate through the adsorption area, wherein one through hole is used for introducing the circulating gas into the gas flow channel, and the other through hole is used for discharging the circulating gas from the gas flow channel. Optionally, the airflow channel includes a plurality of annular grooves disposed inside the adsorption area and centered on the second through hole, and a plurality of radial grooves; The annular grooves are sequentially arranged at intervals in a concentric nested manner, the radial grooves are arranged between two adjacent annular grooves, and the radial grooves are arranged between the second through hole and the innermost annular groove; The first through hole is communicated with the outermost annular groove; The blind holes are arranged on circumferences with different radiuses, corresponding to the annular grooves, on the surface of the adsorption area one by one and are communicated with the corresponding annular grooves. Optionally, the first through hole and the blind hole of the outermost ring are located on the same circumference, and the first through hole passes through the annular groove of the outermost ring; The plurality of radial grooves includes: The plurality of first radial grooves are arranged in the adsorption zone and are used for communicating two adjacent annular grooves in the secondary outer ring; the second radial grooves are arranged on the surface of the adsorption area and are used for connecting the first through holes with blind holes of the secondary outer ring; And the at least one third radial groove is arranged on the surface of the adsorption area and is used for connecting the second through hole and the blind hole of the innermost ring. Optionally, a plurality of first through holes and a plurality of blind holes are formed in the circumference of the outermost ring, and the p