A twin-wafer processing chamber and method of controlling the same

Abstract

The application discloses a double-wafer processing cavity and a control method thereof. The double-wafer processing cavity comprises a cavity assembly provided with a sealed cavity; a supporting assembly arranged in the cavity, comprising a supporting base, a lifting shaft and a wafer supporting plate, the wafer supporting plate is layered and stacked on the supporting base and supports a first wafer and a second wafer respectively; an upper lamp array assembly and a lower lamp array assembly are arranged in axial correspondence with the first wafer and the second wafer and are installed outside the cavity; a temperature sensor for monitoring the temperature of the wafer; wherein the lifting shaft drives the supporting assembly to lift through a transmission mechanism to adjust the distance between the wafer and the lamp array assembly. Through the arrangement of the upper lamp array assembly, the lower lamp array assembly and the layered wafer supporting plate, the double-wafer is synchronously heated in the same cavity, the wafer heating efficiency is improved, and through the arrangement of the lifting-adjustable supporting assembly, the difference between the temperatures of the two wafers can be reduced and the temperature uniformity of the two wafers can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and in particular to a dual-wafer processing cavity and a control method thereof. BACKGROUND

[0002] In the field of semiconductor manufacturing, PVD (Physical Vapor Deposition) and CVD (Chemical Vapor Deposition) are two extremely critical thin film deposition technologies. In a PVD device, a load lock cavity, a heating and degassing cavity, and a cooling cavity are important components of the device. The load lock cavity is used for the transition of the device from the atmosphere to the vacuum, so that the process cavity can always be in a high cleanliness and high vacuum environment to ensure the smooth progress of the process. The heating and degassing cavity is used to heat and remove water vapor and volatile impurities on the wafer surface to ensure the quality of the wafer surface coating; the cooling cavity is used to cool the coated wafer to ensure that the wafer temperature is within a reasonable range when it is transmitted to the wafer boat that carries the wafer. In the existing technology, the load lock cavity, the heating and degassing cavity, and the cooling cavity are usually independent, and when used, the wafer needs to be sequentially transmitted to each cavity for operation. For example, after the wafer is placed in the load lock cavity, vacuum is applied, the cavity pressure changes from atmospheric state to vacuum state, and then the wafer is transmitted to the heating and degassing cavity for heating and degassing; after degassing is completed, the wafer is transmitted to the process cavity by a mechanical hand for the next step of thin film deposition process; after the process is completed, the wafer is transmitted to the cooling cavity for cooling; after cooling is completed, the wafer is transmitted to the load lock cavity, the cavity is pressurized to change the pressure from vacuum to atmospheric state, and the wafer is transmitted to the Foup (box). Due to the need for multiple processing cavities, the thin film deposition device is large in size, the preheating and cooling cavities are independent, the cavity utilization rate is not high, and the device efficiency is low and the production cost is high.

[0003] In the Chinese patent document with publication number CN113981416A, a multifunctional wafer pretreatment cavity is disclosed, which includes a cavity, a wafer carrying device, a preheating device, a heat conducting device, a cooling device, a first driving device, a second driving device, and a controller. The wafer carrying device includes a carrying disc and a plurality of support pins. The heat conducting device is located directly above the wafer, and the cooling device is located in the carrying disc. The controller is connected with the first driving device and the second driving device. When in the preheating mode, the support pins are raised to support the wafer, and the preheating device is started. When in the cooling mode, the support pins are lowered, and the wafer is placed on the carrying disc.

[0004] In the above disclosed patent document, although the preheating device and the cooling device are integrated in one cavity, so that one cavity has multiple uses, the number of cavities used by the wafer processing equipment is reduced, and the problem of large equipment size is alleviated to some extent. However, in the existing thin film deposition equipment, multiple cavities are included, and the processing of one wafer is completed through multiple cavities. The equipment capacity is often limited by the time-consuming process. In actual production, the preheating process of the wafer is the bottleneck process, which affects the WPH (Wafers Per Hour) efficiency of the equipment. Since the chamber only supports the heating or cooling of one wafer at a time, the problem of low efficiency of wafer preheating process has not been solved. Therefore, it is necessary to improve the wafer heating efficiency, that is, to reduce the time consumption of single wafer heating, so as to improve the overall capacity of the equipment. SUMMARY

[0005] The purpose of the present application is to provide a double wafer processing cavity and a control method thereof, which can simultaneously heat two wafers in the same cavity, improve wafer heating efficiency, and reduce the difference between the temperatures of the two wafers.

[0006] To solve the above technical problems, an embodiment of the present application provides a technical solution as follows: a double wafer processing cavity, comprising: a cavity assembly provided with a sealed chamber; a support assembly arranged in the chamber, comprising a support base, a lifting shaft and a wafer support plate; one end of the lifting shaft is connected with the support base, and the other end is connected with a transmission mechanism; the wafer support plate is layered and stacked on the support base, and respectively supports a first wafer and a second wafer; an upper lamp array assembly and a lower lamp array assembly are installed on the outer side of the two ends of the chamber in the axial direction, and are arranged in axial correspondence with the first wafer and the second wafer for heating the first wafer and the second wafer; a temperature monitoring unit comprising a first temperature sensor and a second temperature sensor fixed to the wafer support plate, the first temperature sensor is used for monitoring the temperature of the first wafer, and the second temperature sensor is used for monitoring the temperature of the second wafer; wherein the lifting shaft drives the support assembly to rise and fall through the transmission mechanism, adjusts the distance between the first wafer and the second wafer and the upper lamp array assembly and the lower lamp array assembly to optimize the temperature uniformity of the first wafer and the second wafer.

[0007] Further, the cavity assembly comprises a cavity, a cavity cover installed on the top of the cavity, an upper mounting plate and a lower mounting plate respectively installed on the cavity cover and the bottom of the cavity, an upper light transmission plate and a lower light transmission plate respectively connected to the upper mounting plate and the lower mounting plate, and the cavity, the cavity cover, the upper mounting plate, the upper light transmission plate, the lower mounting plate and the lower light transmission plate form a sealed chamber, and the upper lamp array assembly and the lower lamp array assembly are respectively installed on the outer side of the upper mounting plate and the lower mounting plate.

[0008] Further, the upper light array assembly and the lower light array assembly radiate light to heat the first wafer and the second wafer through the upper light-transmitting plate and the lower light-transmitting plate, respectively, and the light-transmitting rate of the light-transmitting plate to the light array radiation energy is greater than 90%.

[0009] Further, the upper light-transmitting plate and the lower light-transmitting plate are made of quartz, sapphire or transparent ceramic.

[0010] Further, the upper light array assembly comprises first lamp beads arranged towards the first wafer, and the lower light array assembly comprises second lamp beads arranged towards the second wafer, and the first lamp beads and the second lamp beads are arranged in a concentric circle or a matrix array.

[0011] Further, the lifting shaft is coaxially arranged with the support base, and the lifting shaft can drive the support assembly to rotate around the lifting shaft through the transmission mechanism.

[0012] Further, the double-wafer processing cavity supports three working modes:

[0013] Double-wafer mode: simultaneously heating the first wafer and the second wafer;

[0014] Single-wafer mode: heating a single wafer by only starting the upper light array assembly or the lower light array assembly;

[0015] Double-side heating mode: simultaneously heating the same wafer by the upper light array assembly and the lower light array assembly.

[0016] To solve the above technical problems, the application further provides a double-wafer processing cavity control method for heating control of the built-in wafer of the double-wafer processing cavity, comprising the following steps:

[0017] Real-time monitoring of the temperature of the first wafer and the second wafer by a temperature sensor;

[0018] Calculating the temperature difference of the first wafer and the second wafer based on the feedback signal of the temperature sensor, and controlling the lifting movement of the support assembly according to a preset condition to adjust the distance between the wafer and the light array assembly.

[0019] Further, according to the wafer processing process requirement, the temperature deviation allowable range of the first wafer and the second wafer is set as , and the preset condition is configured as:

[0020] When , and , that is, when the temperature of the first wafer is higher than that of the second wafer, the support assembly moves downward by X millimeters, that is, the distance between the first wafer and the upper light array assembly increases by X millimeters, and the distance between the second wafer and the lower light array assembly decreases by X millimeters, and the heating continues;

[0021] When When the first wafer temperature is lower than the second wafer temperature, the wafer support assembly moves upward by X millimeters, that is, the distance between the first wafer and the upper lamp array assembly is reduced by X millimeters, the distance between the second wafer and the lower lamp array assembly is increased by X millimeters, and the heating continues, wherein 0X≤3; When the first wafer temperature is lower than the second wafer temperature, the wafer support assembly moves upward by X millimeters, that is, the distance between the first wafer and the upper lamp array assembly is reduced by X millimeters, the distance between the second wafer and the lower lamp array assembly is increased by X millimeters, and the heating continues, wherein 0X≤3;

[0022] When the first wafer temperature is lower than the second wafer temperature, the wafer support assembly moves upward by X millimeters, that is, the distance between the first wafer and the upper lamp array assembly is reduced by X millimeters, the distance between the second wafer and the lower lamp array assembly is increased by X millimeters, and the heating continues, wherein 0X≤3; When the first wafer temperature is lower than the second wafer temperature, the wafer support assembly moves upward by X millimeters, that is, the distance between the first wafer and the upper lamp array assembly is reduced by X millimeters, the distance between the second wafer and the lower lamp array assembly is increased by X millimeters, and the heating continues, wherein 0X≤3;

[0023] Wherein, is the difference between the temperature of the first wafer and ; is the difference between the temperature of the second wafer and ; is the average of the temperature of the first wafer and the temperature of the second wafer.

[0024] Further, the lifting control interval period of the support assembly is t seconds, wherein 0

[0025] The double-wafer processing cavity provided by the present application, compared with the prior art, provides stable support for double-wafer loading through the wafer support plates layered and stacked on the support base, and through the axial corresponding arrangement of the upper lamp array assembly and the lower lamp array assembly with the first wafer and the second wafer, the double-wafer can be heated synchronously in the same chamber, effectively improving the heating efficiency of the wafer, and through the arrangement of the lifting shaft driving the support assembly to lift, the distance between the wafer and the lamp array assembly is adjusted, which can reduce the difference between the temperatures of the two wafers and improve the temperature uniformity of the two wafers. The double-wafer processing cavity control method provided by the present application, through the monitoring of the first wafer temperature and the second wafer temperature by the built-in temperature sensor in the chamber, based on the temperature difference between the first wafer and the second wafer, the support assembly is lifted in real time, the distance between the wafer and the lamp array assembly is adjusted, which can effectively improve the uniformity of the heating temperature of the two wafers. BRIEF DESCRIPTION OF DRAWINGS

[0026] One or more embodiments are illustrated by way of example in the figures that form part of this document, and which show by way of example the principles of the embodiments. The same reference numbers in different figures identify the same elements or the similar elements. The figures in the drawings are not necessarily to scale, except if so expressly indicated.

[0027] Figure 1 is a double-wafer processing cavity cross-sectional structure schematic diagram in the embodiments of the present application;

[0028] Figure 2 is a support assembly structure schematic diagram in an embodiment of the present application;

[0029] Figure 3 Support assembly structure schematic diagram in another embodiment of the present application;

[0030] Figure 4 Control method steps flow chart of double-wafer processing cavity in an embodiment of the present application.

[0031] Legend: 1, cavity; 100, chamber; 2, cavity cover; 3, upper mounting plate; 4, upper light-transmitting plate; 5, upper lamp array assembly; 51, first lamp bead; 6, lower lamp array assembly; 61, second lamp bead; 7, lower mounting plate; 8, lower light-transmitting plate; 9, first wafer; 10, 16, first wafer support plate; 11, 13, 17, 19, wafer support; 12, 18, second wafer support plate; 14, 14', support base; 15, second wafer; 20, 20', lifting shaft; 21, first cover plate; 22, first temperature sensor; 23, second cover plate; 24, second temperature sensor. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. However, those skilled in the art can understand that, in the embodiments of the present application, many technical details are presented in order to make the readers better understand the present application. However, the technical solutions claimed in each claim of the present application can be implemented even without these technical details and based on various changes and modifications of the following embodiments.

[0033] It should be noted that, if the present application embodiments involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0034] As Figures 1-3As shown, one embodiment of the present application relates to a dual wafer processing cavity, comprising: a cavity assembly, including a cavity 1, a bottom connected to a vacuum pump, a cavity cover 2 installed on the top of the cavity 1, an upper mounting plate 3 and a lower mounting plate 7 respectively installed on the bottom of the cavity cover 2 and the cavity 1, the upper mounting plate 3 corresponding to the installation of an upper light transmission plate 4, and the lower mounting plate 7 corresponding to the installation of a lower light transmission plate 8, the cavity 1, the cavity cover 2, the upper mounting plate 3, the upper light transmission plate 4, the lower mounting plate 7 and the lower light transmission plate 8 form a closed cavity chamber 100. In order to increase the sealing effect of the cavity chamber 100, the cavity 1 and the cavity cover 2, the cavity cover 2 and the upper mounting plate 3, the upper mounting plate 3 and the upper light transmission plate 4, the cavity 1 and the lower mounting plate 7, and the lower mounting plate 7 and the lower light transmission plate 8 are all connected by O-shaped sealing rings. The bottom of the cavity 1 is connected to a vacuum pump (not shown in the figure), which can vacuum the cavity chamber 100, so that the vacuum degree of the cavity chamber 100 can meet the process requirements of wafer processing.

[0035] A support assembly is arranged in the cavity chamber 100, comprising a support base 14, 14', a lifting shaft 20, 20' and a wafer support plate, one end of the lifting shaft 20, 20' is connected with the support base 14, 14', the other end is connected with a transmission mechanism (not shown in the figure), and the lifting shaft 20 is connected and sealed with the cavity 1 through a corrugated pipe; the wafer support plate is layered and stacked on the support base 14, 14', and respectively supports a first wafer 9 and a second wafer 15. In order to increase the stability of the wafer placement, each wafer is supported by a plurality of wafer support plates, and the contact surface of the wafer support plate with the same wafer is located in the same plane. In one example, the first wafer 9 is supported by the first wafer support plate 10, 16, and the second wafer 15 is supported by the second wafer support plate 12, 18, and the first wafer 9 and the second wafer 15 are arranged in parallel and spaced apart, wherein the first wafer support plate 10, the second wafer support plate 12 are fixed to one side of the support base through the wafer support 11, 13, and the first wafer support plate 16, the second wafer support plate 18 are fixed to the other side of the support base 14, 14' through the wafer support 17, 19. The contact surface of the first wafer support plate 10, 16 with the first wafer is in the same plane, and the contact surface of the second wafer support plate 12, 18 with the second wafer is in the same plane. In one example, the first wafer support plate 10, 12 and the second wafer support plate 16, 18 are made of stainless steel or aluminum alloy material, preferably, the first wafer support plate 10, 12 and the second wafer support plate 16, 18 are made of glass, sapphire, transparent ceramic or the like, so as to reduce the blocking of the lamp array assembly radiation and improve the wafer heating efficiency and temperature uniformity. The first wafer 9 and the second wafer 15 can also be respectively supported and positioned by three, four or the like wafer support plates uniformly distributed around them.

[0036] The upper lamp array assembly 5 and the lower lamp array assembly 6 are installed outside the axial ends of the chamber 100, the upper lamp array assembly 5 is installed outside the upper mounting plate 3, the lower lamp array assembly 6 is installed outside the lower mounting plate 7, and is arranged axially corresponding to the first wafer 9 and the second wafer 15, for heating the first wafer 9 and the second wafer 15.

[0037] Wherein, the lifting shafts 20, 20' drive the support assembly to lift or lower, to adjust the distance between the wafers and the lamp array assemblies to optimize the temperature uniformity of the wafers, that is, to adjust the distance between the first wafer 9 and the second wafer 15 and the upper lamp array assembly 5 and the lower lamp array assembly 6 to optimize the temperature uniformity of the first wafer 9 and the second wafer 15. For example, when the temperature of the first wafer 9 is higher than that of the second wafer 15, the first wafer 9 can be moved away from the upper lamp array assembly 5 and the second wafer 15 can be moved closer to the lower lamp array assembly 6 by lowering the support assembly, so that the second wafer 15 receives more energy from the radiation than the first wafer 9, to increase the heating rate of the second wafer 15 and reduce the heating rate of the first wafer 9, so that the temperatures of the first wafer 9 and the second wafer 15 are close to each other, and the temperature uniformity between them is improved. Through the arrangement of the lifting shafts 20, 20', during the radiation heating of the wafers, the temperature difference between the two wafers can be adjusted in real time by lifting or lowering according to the temperature feedback of the upper and lower wafers, so as to improve the temperature uniformity of the two wafers.

[0038] Temperature monitoring unit, including first temperature sensor 22 fixed on first wafer support plate 10, 16 and second temperature sensor 24 fixed on second wafer support plate 12, 18, first temperature sensor 22 is used for monitoring the temperature of first wafer 9, and second temperature sensor 24 is used for monitoring the temperature of second wafer 15. In order to improve the accuracy of temperature sensor feedback to wafer temperature, the end of first temperature sensor 22 is arranged as close to first wafer 9 as possible, and is fixed on first wafer support plate 10, 16 through first cover plate 21, and the end of second temperature sensor 24 is arranged as close to second wafer 15 as possible, and is fixed on second wafer support plate 12, 18 through second cover plate 23, so as to improve the accuracy of temperature signal feedback of temperature sensor, preferably, the distance between the temperature measuring point at the end of first temperature sensor 22 and the edge of first wafer 9 is 3-6mm, and the distance between the temperature measuring point at the end of second temperature sensor 24 and the edge of second wafer 15 is 3-6mm; the signal line of temperature sensor is connected to external PLC through the through hole in lifting shaft 20, 20', and the temperature signal is fed back to external control device (not shown in the figure), which is used for transmission of wafer temperature signal and control of wafer temperature. Preferably, in order to further improve the stability and safety of temperature monitoring, a plurality of temperature sensors can also be added, such as one first temperature sensor 22 arranged at each end of first wafer support plate 10, 16, that is, four temperature sensors are used for control and feedback of first wafer 9, and similarly, one second temperature sensor 24 is arranged at each end of first wafer support plate 12, 18, that is, four temperature sensors are used for control and feedback of second wafer 15.

[0039] Functional interface, including wafer loading port (not shown in the figure) and wafer transmission port (not shown in the figure) arranged on both sides of cavity 1 respectively, wafer loading port is used for connecting with EFEM (Equipment Front End Module, equipment front end module) to facilitate receiving wafer sent by EFEM robot, and wafer transmission port is used for connecting with TM (Transfer Module, transfer module) to facilitate transmission of wafer between multiple chambers in the equipment.

[0040] In one embodiment, a double-wafer processing cavity is involved, and a gas inlet device (not shown in the figure) is further connected to the cavity, so that the cavity has the functions of load locking and wafer cooling by using gas in addition to the functions of heating and degassing. In addition, when the lamp array radiation heating is carried out, a small amount of inert gas such as N2 or Ar can also be injected into cavity 100 through gas inlet device to improve the effect of wafer heating and degassing.

[0041] In one embodiment, a dual wafer processing cavity is provided, an upper lamp array assembly 5 is installed above the cavity 1, and a lower lamp array assembly 6 is installed below the cavity 1. The lamp array assemblies radiate light through the light-transmitting plates to the wafer surfaces in the cavity 100 to heat the wafers. The light-transmitting plates have a light transmission rate of greater than 90% for the light radiated by the lamp array assemblies. Specifically, the light radiated by the upper lamp array assembly 5 passes through the upper light-transmitting plate 4 to heat the first wafer 9, and the light radiated by the lower lamp array assembly 6 passes through the lower light-transmitting plate 8 to heat the second wafer 15. The arrangement of the upper lamp array assembly 5 and the lower lamp array assembly 6 radiating and heating the first wafer 9 and the second wafer 15 synchronously enables the simultaneous heating of two wafers in the same cavity 100. Compared with the prior art in which only one wafer can be processed in the same cavity, the dual wafer processing cavity provided by the present application can simultaneously heat two wafers in the same time, effectively improving the efficiency of wafer pre-processing and heating, and further improving the WPH (Wafers Per Hour) efficiency of the semiconductor processing equipment. The upper lamp array assembly 5 includes first lamp beads 51 arranged towards the first wafer 9, and the lower lamp array assembly 6 includes second lamp beads 61 arranged towards the second wafer 15. Preferably, the first lamp beads 51 and the second lamp beads 61 are arranged in concentric circles or matrix arrays to enhance the uniformity of the radiation and heating of the lamp array assemblies.

[0042] In one exemplary example, the upper mounting plate 3 and the lower mounting plate 7 have the same structure, and the upper light-transmitting plate 4 and the lower light-transmitting plate 8 have the same structure to enhance the versatility. The light-transmitting plates 4 and 8 have a light transmission rate of greater than 90% for the light radiated by the lamp array assemblies. The light-transmitting plates 4 and 8 are preferably made of light-transmitting materials such as quartz, sapphire, or transparent ceramic. The structures and radiation energies of the upper lamp array assembly 5 and the lower lamp array assembly 6 can be the same to enhance the versatility, or can be different to match the installation spaces of the upper and lower parts of the cavity 1, which is not limited herein.

[0043] In one embodiment, a dual wafer processing cavity is provided, including a cavity assembly and a support assembly arranged in the cavity 100 of the cavity assembly, as shown in Figure 3As shown, the support assembly comprises a support base 14' and a lifting shaft 20' arranged coaxially, the support base 14' is stacked with wafer support plates in layers, which respectively support the first wafer 9 and the second wafer 15, the contact surfaces of the wafer support plates with the same wafer are located in the same plane, preferably, the first wafer 9 and the second wafer 15 are arranged in parallel and spaced apart, one end of the lifting shaft 20' penetrating through the bottom of the cavity 1 is connected with the transmission mechanism, the lifting shaft 20' can not only drive the support assembly to lift through the transmission mechanism, but also can drive the support assembly to rotate around the lifting shaft 20' as the rotation shaft, thereby driving the wafer loaded on the wafer support plate to rotate, further improving the uniformity of the heating temperature of the two wafers. The support base 14' and the lifting shaft 20' are made of stainless steel or aluminum alloy material, preferably, the support base 14' and the lifting shaft 20' are made of high light transmission materials such as quartz, sapphire glass, transparent ceramic and the like, so as to avoid the radiation energy from being blocked to affect the heating of the wafer and improve the temperature uniformity; the wafer support plate is made of quartz glass material, in the prior art, when the wafer support plate is made of metal structure, there are two problems, one is that the thermal conductivity of metal is large, for example, the thermal conductivity of stainless steel is 18 W / (m·K), which will make the heat of the wafer edge and the contact area between the wafer and the wafer support plate be quickly conducted away by the metal support plate, so that the temperature of the wafer near the contact area is reduced, resulting in poor wafer temperature uniformity, by using quartz glass material for the wafer support plate, the thermal conductivity of the wafer support plate can be greatly reduced, and the light transmission rate of the wafer support plate is improved, which is beneficial to improve the uniformity of the wafer temperature.

[0044] The double-wafer processing cavity provided by the application can provide three working modes according to actual conditions:

[0045] Double-wafer mode: the wafer support plates simultaneously load the first wafer 9 and the second wafer 15, the upper lamp array assembly 5, the first wafer 9, the second wafer 15 and the lower lamp array assembly 6 are coaxially arranged, the upper lamp array assembly 5 and the lower lamp array assembly 6 are simultaneously turned on, and the first wafer 9 and the second wafer 15 are synchronously heated, in this working mode, the upper lamp array assembly 5 is the main heating source of the first wafer 9, and the lower lamp array assembly 6 is the main heating source of the second wafer 15;

[0046] Single-wafer mode: the wafer support in the cavity 100 only loads one wafer, when the first wafer 9 is loaded, the corresponding upper lamp array assembly 5 is turned on to heat it, when the second wafer 15 is loaded, the lower lamp array assembly 6 is turned on to heat it, only the upper lamp array assembly 5 or the lower lamp array assembly 6 is turned on to heat the single wafer, so as to save energy;

[0047] Double-side heating mode: in order to improve the heating efficiency of the single wafer, when the wafer support in the cavity 100 only loads one wafer, the upper lamp array assembly 5 and the lower lamp array assembly 6 are simultaneously turned on to heat the same wafer, so as to improve the wafer heating rate and improve the wafer heating efficiency.

[0048] To solve the technical problems proposed in the present application, realize the heating treatment of two wafers in the same cavity 1 at the same time, improve the wafer heating efficiency and reduce the difference between the temperatures of the two wafers, an embodiment of the present application relates to a double-wafer processing cavity control method for the heating control of the double-wafer processing cavity for the two wafers built-in, comprising the following steps:

[0049] The temperature of the first wafer 9 and the second wafer 15 is monitored in real time by the temperature sensor built-in in the chamber 100;

[0050] The temperature sensor feeds back the temperature signals of the first wafer 9 and the second wafer 15 to the control device, the control device calculates the temperature difference of the first wafer 9 and the second wafer 15 based on the feedback signals of the temperature sensor, and adjusts the distance between the wafers and the lamp array assembly according to the preset conditions based on the temperature difference of the first wafer 9 and the second wafer 15.

[0051] According to the wafer processing process requirements, the temperature deviation allowed range of the first wafer 9 and the second wafer 15 is set as The preset conditions of the control device for controlling the movement of the support assembly are as follows:

[0052] When , and , that is, when the temperature of the first wafer 9 is higher than the temperature of the second wafer 15, the support assembly moves downward by X millimeters, that is, the distance between the first wafer 9 and the upper lamp array assembly 5 increases by X millimeters, and the distance between the second wafer 15 and the lower lamp array assembly 6 decreases by X millimeters, and the heating continues;

[0053] When , and , that is, when the temperature of the first wafer 9 is lower than the temperature of the second wafer 15, the support assembly moves upward by X millimeters, that is, the distance between the first wafer 9 and the upper lamp array assembly 5 decreases by X millimeters, and the distance between the second wafer 15 and the lower lamp array assembly 6 increases by X millimeters, and the heating continues; preferably, 0

[0054] When , it indicates that the temperature difference between the first wafer 9 and the second wafer 15 is within the process allowed deviation range, and the support assembly does not adjust and continues to heat;

[0055] Wherein, is the difference between the temperature of the first wafer and ; is the difference between the temperature of the second wafer and , and is the average of the temperature of the first wafer and the temperature of the second wafer.

[0056] The lift control interval period of the support assembly is t seconds, 0 < t < 10, that is, the control device judges the preset condition every t seconds during the wafer heating process, and controls the movement of the support assembly according to the judgment result, adjusts the distance between the wafer and the lamp array assembly, so as to improve the uniformity of the heating temperature between the two wafers.

[0057] In one embodiment, a dual-wafer processing cavity control method is involved. Since the temperature sensor is arranged apart from the wafer and does not directly contact the wafer, there is a certain error between the wafer temperature value measured by the temperature sensor and the actual wafer temperature. Therefore, it is necessary to calibrate the temperature sensor measurement data. The temperature sensor calibration process is as follows:

[0058] Step 1: Place two wafers in the cavity, and place temperature detectors on the two wafers, respectively. The temperature measured by the temperature detector is equal to the actual wafer temperature. Take 10℃ as the temperature gradient, record the temperature data of the temperature sensor and the temperature detector, as shown in Table 1 Temperature Calibration Data Record Table, and find the function relationship between the temperature sensor and the actual wafer temperature.

[0059] Table 1 Temperature Calibration Data Record Table

[0060]

[0061] Based on the above table data, the function relationship is calculated as follows:

[0062] The relationship between the temperature of the first temperature sensor and the temperature of the first wafer, that is, the calibration function of the first temperature sensor is A = f(TA);

[0063] The relationship between the temperature of the second temperature sensor and the temperature of the second wafer, that is, the calibration function of the second temperature sensor is B = g(TB).

[0064] Step 2: Perform wafer heating, and collect temperature sensor temperature data at a time gradient of 1s, as shown in Table 2 Temperature Sensor Time-sharing Data Record Table.

[0065] Table 2 Temperature Sensor Time-sharing Data Record Table

[0066]

[0067] According to the temperature sensor calibration function, the temperature sensor time-sharing data is calibrated, and the calibrated data is recorded in Table 3 Temperature Calibration Data Record Table.

[0068] Table 3 Temperature Calibration Data Record Table

[0069]

[0070] During the wafer heating process, the average temperature of the first wafer 9 and the second wafer 15 at any time t is:

[0071]

[0072] The difference between the temperature of the first wafer 9 and the average temperature at any time t is:

[0073]

[0074] The difference between the temperature of the second wafer 15 and the average temperature at any time t is:

[0075]

[0076] During the wafer heating process, the data measured by the first temperature sensor 22 and the second temperature sensor 24 are calibrated to obtain the temperature of the first wafer 9 and the second wafer 15 at any time t, and the movement of the support assembly is determined according to the temperature difference between the first wafer 9 and the second wafer 15, and the lifting control of the support assembly is performed according to the preset condition.

[0077] In an exemplary example, the preset condition is executed as follows:

[0078] When , and , that is, when the temperature of the first wafer 9 is higher than the temperature of the second wafer 15, the support assembly moves downward by 1 mm, that is, the distance between the first wafer 9 and the upper lamp array assembly 5 increases by 1 mm, and the distance between the second wafer 15 and the lower lamp array assembly 6 decreases by 1 mm, and the heating continues.

[0079] When , and , that is, when the temperature of the first wafer 9 is lower than the temperature of the second wafer 15, the wafer support assembly moves upward by 1 mm, that is, the distance between the first wafer 9 and the upper lamp array assembly 5 decreases by 1 mm, and the distance between the second wafer 15 and the lower lamp array assembly 6 increases by 1 mm, and the heating continues.

[0080] When , it indicates that the temperature difference between the first wafer 9 and the second wafer 15 is within the process allowable deviation range, and the support assembly does not adjust and continues to heat.

[0081] Wherein, is the difference between the temperature of the first wafer 9 at any heating time t and . is the difference between the temperature of the second wafer 15 at any heating time t and , and the is the average of the temperature of the first wafer 9 and the temperature of the second wafer 15 at any heating time t.

[0082] In one embodiment, a dual wafer processing chamber control method is provided, which includes determining the motion of the support assembly every 1-10 seconds, and controlling the lifting of the support assembly according to preset conditions until the average temperature of the wafers reaches the required temperature and the temperature deviation between the two wafers is within the allowable range.

[0083] In one embodiment, a dual wafer processing chamber is provided, which includes wafer support plates stacked on a support base to provide stable support for the two wafers, and upper and lower lamp array assemblies arranged axially corresponding to the first and second wafers, so that the two wafers can be heated synchronously in the same chamber, effectively improving the heating efficiency of the wafers. The distance between the wafers and the lamp array assemblies is adjusted by driving the support assembly to rise and fall by the lifting shaft, which can reduce the temperature difference between the two wafers and improve the temperature uniformity of the two wafers. A dual wafer processing chamber control method is provided, which includes monitoring the temperature of the first and second wafers by the built-in temperature sensor in the chamber, and controlling the lifting of the support assembly in real time based on the temperature difference between the first and second wafers, and adjusting the distance between the wafers and the lamp array assemblies, which can effectively improve the uniformity of the heating temperature of the two wafers.

[0084] Although the present application has been disclosed with reference to the preferred embodiments, it is not intended to limit the present application, and any person skilled in the art can make some modifications and improvements without departing from the spirit and scope of the present application, therefore the protection scope of the present application is defined by the claims.

Claims

1. A twin-wafer processing chamber, comprising: The application relates to a double-wafer heating device. The device comprises a cavity assembly provided with a closed cavity (100), a support assembly arranged in the cavity (100) and comprising a support base (14, 14'), a lifting shaft (20, 20') and wafer support plates, one end of the lifting shaft (20, 20') being connected to the support base (14, 14'), the other end being connected to a transmission mechanism, the wafer support plates being stacked on the support base (14, 14') and supporting a first wafer (9) and a second wafer (15) respectively, an upper lamp array assembly (5) and a lower lamp array assembly (6) being arranged on the outer sides of the two ends of the cavity (100) in the axial direction and being arranged in axial correspondence with the first wafer (9) and the second wafer (15) for heating the first wafer (9) and the second wafer (15), a temperature monitoring unit comprising a first temperature sensor (22) and a second temperature sensor (24) fixed to the wafer support plates, the first temperature sensor (22) being used for monitoring the temperature of the first wafer (9) and the second temperature sensor (24) being used for monitoring the temperature of the second wafer (15). The lifting shaft (20, 20') drives the support assembly to lift or lower through the transmission mechanism, the distance between the first wafer (9) and the second wafer (15) and the upper lamp array assembly (5) and the lower lamp array assembly (6) is adjusted to optimize the temperature uniformity of the first wafer (9) and the second wafer (15). The cavity assembly comprises a cavity (1), a cavity cover (2) arranged on the top of the cavity (1), an upper mounting plate (3) and a lower mounting plate (7) arranged on the cavity cover (2) and the bottom of the cavity (1) respectively, an upper light transmission plate (4) and a lower light transmission plate (8) connected to the upper mounting plate (3) and the lower mounting plate (7) respectively, the cavity (1), the cavity cover (2), the upper mounting plate (3), the upper light transmission plate (4), the lower mounting plate (7) and the lower light transmission plate (8) forming a closed cavity (100), the upper lamp array assembly (5) and the lower lamp array assembly (6) being arranged on the outer sides of the upper mounting plate (3) and the lower mounting plate (7) respectively. The radiation light of the upper lamp array assembly (5) and the lower lamp array assembly (6) penetrates the upper light transmission plate (4) and the lower light transmission plate (8) to heat the first wafer (9) and the second wafer (15), the light transmittance of the light transmission plate to the radiation energy of the lamp array is greater than 90%. The material of the upper light transmission plate (4) and the lower light transmission plate (8) is quartz, sapphire or transparent ceramic.

2. The twin-wafer processing chamber of claim 1, wherein, The upper lamp array assembly (5) comprises first lamp beads (51) arranged towards the first wafer (9), the lower lamp array assembly (6) comprises second lamp beads (61) arranged towards the second wafer (15), the first lamp beads (51) and the second lamp beads (61) are arranged in concentric circles or matrix array.

3. The twin-wafer processing chamber of claim 2, wherein, ​ 4. The twin-wafer processing chamber of claim 3, wherein, ​ 5. The twin-wafer processing chamber of claim 3, wherein, ​ 6. The twin-wafer processing chamber of claim 1, wherein, The lifting shaft (20') is coaxially arranged with the support base (14'), and the lifting shaft (20') can drive the support assembly to rotate around the lifting shaft (20') through the transmission mechanism.

7. The twin-wafer processing chamber of claim 1, wherein, The dual-wafer processing cavity supports three working modes: Dual-wafer mode: simultaneously heating the first wafer (9) and the second wafer (15); Single-wafer mode: only turning on the upper lamp array assembly (5) or the lower lamp array assembly (6) to heat a single wafer; Dual-side heating mode: simultaneously heating the same wafer by the upper lamp array assembly (5) and the lower lamp array assembly (6).

8. A twin-wafer processing chamber control method, comprising: The heating control method for the built-in wafers of the dual-wafer processing cavity according to any one of claims 1-7 comprises the following steps: Real-time monitoring of the temperatures of the first wafer (9) and the second wafer (15) by temperature sensors; Based on the feedback signals of the temperature sensors, calculating the temperature difference between the first wafer (9) and the second wafer (15), and controlling the lifting movement of the support assembly according to preset conditions to adjust the distance between the wafers and the lamp array assemblies.

9. The dual-wafer processing cavity control method according to claim 8, wherein the lifting control interval period of the support assembly is t seconds, and 0 < t ≤ 10. According to the requirement of wafer processing process, the temperature deviation allowable range of the first wafer (9) and the second wafer (15) is set as , and the preset condition is configured as: When When, and When the first wafer (9) temperature is higher than the second wafer (15) temperature, the support assembly moves downwards X mm, i.e. the first wafer (9) distance from the upper lamp array assembly (5) increases by X mm, the second wafer (15) distance from the lower lamp array assembly (6) decreases by X mm, heating continues. When and When the first wafer temperature is lower than the second wafer (15) temperature, the support assembly moves upwards by X mm, i.e. the first wafer (9) is moved X mm away from the upper lamp array assembly (5) and the second wafer (15) is moved X mm away from the lower lamp array assembly (6), and heating continues. When X indicates that the temperature difference between the first wafer (9) and the second wafer (15) is within the process allowable deviation range, the support assembly does not adjust and continues to heat, wherein 0X≤3. wherein is the difference between the temperature of the first wafer (9) and ; is the difference between the temperature of the second wafer (15) and ; is the average of the temperature of the first wafer (9) and the temperature of the second wafer (15).

10. The twin-wafer processing chamber control method of claim 9, wherein, ​

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