Rapid heat treatment equipment for wafer

Abstract

The utility model provides rapid heat treatment equipment for wafers, which comprises a process chamber provided with an air inlet, an air outlet, an upper heating device, a lower heating device and a wafer heating treatment table. The wafer heating processing table is sequentially provided with an air floatation driving mechanism and a rotary table in the direction from the lower heating device to the upper heating device, the rotary table is arranged above the air floatation driving mechanism and connected with the lower heating device through a rotating shaft, and the air floatation driving mechanism can drive the rotary table to be in an air floatation shape and rotate relative to the rotating shaft. The rotary table is provided with at least three supporting columns used for supporting the periphery of the wafer in the circumferential direction, the end portions of the supporting columns are in an L shape, the platform portions of the L-shaped end portions are used for placing the edge of the wafer, the vertical portions are used for limiting the wafer, relative sliding between the supporting columns and the wafer is prevented, abrasion of the supporting columns is reduced, regular replacement is not needed, and cost is saved. And the supporting columns are only supported in the peripheral direction of the wafer, so that the temperature uniformity in the wafer is not influenced, and the temperature uniformity of the wafer is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor device manufacturing, in particular to a rapid heat treatment device for wafers. Background Art

[0002] In the semiconductor device manufacturing process, the Rapid Thermal Processing (RTP) process is used to quickly and uniformly heat the wafer. It is usually used in the activation and diffusion of dopants after ion implantation, the annealing treatment after the formation of metal silicide, and the annealing treatment of the gate oxide layer.

[0003] During the RTP process, the wafer is placed on a wafer support device, and heating light sources are provided above and below the wafer. When the wafer rotates, it is heated by the energy radiated by the heating light source located above the wafer. Figure 1 The wafer support device supports the wafer 1 through three quartz ejector pins 2 and rotates the wafer 1. The end of the ejector pin 2 for contacting the wafer 1 is a pointed end. Therefore, the following technical problems exist:

[0004] 1. As the number of uses increases, the tip of the ejector pin 2 will be worn, and the ejector pin 2 needs to be replaced regularly, which causes greater loss and increases costs;

[0005] 2. Ejector pin 2 is in contact with the back of wafer 1. Therefore, when wafer 1 is heated, heat conduction will leave three cold spots 3 on wafer 1. Please refer to Figure 2 , which has a certain impact on the uniformity of heating;

[0006] 3. Since the contact area between ejector pin 2 and wafer 1 is very small, when wafer 1 is slightly deformed by heat or ejector pin 2 is severely worn, wafer 1 rotates at high speed, and the relative position of wafer 1 and ejector pin 2 changes, causing the rotation of the wafer to shift and collide with surrounding components, causing the edge of the wafer to wear and produce particles. Utility Model Content

[0007] To solve the above technical problems, the utility model provides a rapid thermal processing equipment for wafers, comprising a process chamber, wherein the process chamber is provided with an air inlet, an air outlet, an upper heating device, a lower heating device and a wafer heating processing table; the wafer heating processing table is arranged between the upper heating device and the lower heating device; the wafer heating processing table is communicated with the air inlet and the air outlet, and is isolated from the airflow of the upper heating device and the lower heating device; the wafer heating processing table is provided with an air floating drive mechanism and a turntable in sequence from the lower heating device to the upper heating device, the turntable is arranged above the air floating drive mechanism and is connected to the lower heating device through a rotating shaft, the air floating drive mechanism can drive the turntable to be in an air floating state and rotate relative to the rotating shaft, and at least three support columns for supporting the outer circumference of the wafer are arranged on the turntable, the end of the support column is L-shaped, the platform at the L-shaped end is used to place the edge of the wafer, and the vertical part is used to limit the wafer.

[0008] Preferably, the heating sources in the lower heating device and the upper heating device are halogen tungsten lamps.

[0009] Preferably, transparent quartz windows are provided at positions of the upper heating device and the lower heating device facing the wafer heating processing station.

[0010] Preferably, the turntable is also made of transparent quartz material, and a surface of the turntable facing the air-floating drive mechanism is provided with fish-scale-like patterns.

[0011] Preferably, the main body of the air-floating drive mechanism is made of transparent quartz.

[0012] Preferably, the air-floating drive mechanism is provided with at least three first air-floating stators for stably floating the turntable in a plane.

[0013] Preferably, the air-floating drive mechanism is further provided with a second air-floating stator, through which an airflow of a certain pressure is delivered to the back of the turntable to drive the turntable to accelerate or maintain a preset rotation speed.

[0014] Preferably, the air-floating drive mechanism is further provided with a third air-floating stator, through which an airflow with a certain pressure is delivered to the back side of the turntable to decelerate the rotating turntable.

[0015] Preferably, the support column is clamped on the turntable, and the support column is made of transparent quartz. Compared with the prior art, the technical solution of the embodiment of the utility model has the following beneficial effects:

[0016] 1. In the utility model, since the end of the support column that supports the wafer that contacts the wafer is L-shaped, the platform at the L-shaped end is used to place the edge of the wafer, and the vertical part is used to limit the wafer to prevent relative sliding between the support column and the wafer. Therefore, the wear of the support column is very small, and it does not need to be replaced regularly, thereby reducing the loss and saving costs.

[0017] 2. The utility model increases the contact area with the edge of the wafer through the L-shaped end of the support column, and the vertical part of the L-shaped end can limit the wafer, ensuring that the wafer will not collide with other parts due to deviation during rotation, causing edge wear of the wafer.

[0018] 3. The wafer includes a peripheral area and a middle area within the peripheral area. Based on this, the utility model supports the support column only on the peripheral circumference of the wafer, and the middle area of ​​the wafer does not contact the support column. Therefore, the support column will not affect the temperature uniformity in the wafer, ensuring the temperature uniformity of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a schematic diagram of the structure of a rapid thermal processing device for wafers in the prior art;

[0021] Figure 2 It is a heat diagram of a wafer during a rapid thermal processing process in the prior art;

[0022] Figure 3 It is a structural schematic diagram of a rapid thermal processing device for wafers according to an embodiment of the utility model;

[0023] Figure 4 It is a structural schematic diagram of a wafer heating treatment station according to an embodiment of the utility model;

[0024] Figure 5 It is a structural schematic diagram of the air floating drive mechanism according to one embodiment of the utility model;

[0025] Figure 6 It is a heat diagram of a wafer in a rapid thermal processing process according to an embodiment of the present utility model;

[0026] Description of reference numerals:

[0027] 1--wafer;

[0028] 2--thimble;

[0029] 3--cold spot;

[0030] 4--Process chamber;

[0031] 401--Air inlet;

[0032] 402--Air outlet;

[0033] 5--Upper heating device;

[0034] 501--upper heating source;

[0035] 502--upper transparent quartz window;

[0036] 6--Lower heating device;

[0037] 601--lower heating source;

[0038] 602--lower transparent quartz window;

[0039] 7--Support column;

[0040] 701--Platform;

[0041] 702--vertical part;

[0042] 8--Turntable;

[0043] 9--rotating shaft;

[0044] 10--Air floating drive mechanism;

[0045] 1001--the first air-floating stator;

[0046] 1002--second air-floating stator;

[0047] 1003--The third air-floating stator;

[0048] 1004--The third gas supply pipe;

[0049] 1005--First air supply pipe;

[0050] 1006--The second air supply pipe. DETAILED DESCRIPTION

[0051] In order to solve the technical problems in the background technology, the utility model provides a rapid thermal processing equipment for wafers, including a process chamber, the process chamber is provided with an air inlet, an air outlet, an upper heating device, a lower heating device and a wafer heating processing table; the wafer heating processing table is arranged between the upper heating device and the lower heating device; the wafer heating processing table is communicated with the air inlet and the air outlet, and is isolated from the airflow of the upper heating device and the lower heating device; the wafer heating processing table is sequentially provided with an air floating drive mechanism and a turntable in the direction from the lower heating device to the upper heating device, the turntable is arranged above the air floating drive mechanism and is connected to the lower heating device through a rotating shaft, the air floating drive mechanism can drive the turntable to be air-floating and rotate relative to the rotating shaft, and at least three support columns for supporting the outer circumference of the wafer are arranged on the turntable, the end of the support column is L-shaped, the platform at the L-shaped end is used to place the edge of the wafer, and the vertical part is used to limit the wafer.

[0052] In the utility model, since the support column that supports the wafer has an L-shaped end that contacts the wafer, the platform at the L-shaped end is used to place the edge of the wafer, and the vertical part is used to limit the wafer to prevent relative sliding between the support column and the wafer. Therefore, the wear of the support column is very small and does not need to be replaced regularly, resulting in low loss and cost savings.

[0053] Moreover, the contact area between the L-shaped end and the edge of the wafer is increased, and the L-shaped end ensures that the wafer will not collide with other parts due to deviation during rotation, causing the edge of the wafer to wear and generate particles.

[0054] Furthermore, the wafer includes a peripheral area and a middle area within the peripheral area, that is, the peripheral area is located on the periphery of the middle area. Since there is no chip or no complete chip in the peripheral area of ​​the wafer, there is no need to ensure the temperature uniformity of the peripheral area of ​​the wafer, and only the temperature uniformity of the middle area needs to be ensured. Based on this, the utility model supports the support column only on the peripheral circumference of the wafer, and the middle area of ​​the wafer does not contact the support column. Therefore, the support column will not affect the temperature uniformity in the wafer, thereby ensuring the temperature uniformity of the wafer.

[0055] In order to make the above-mentioned purposes, features and beneficial effects of the utility model more obvious and easy to understand, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0056] Please refer to Figures 3 to 6The present embodiment provides a rapid thermal processing device for wafers, comprising a process chamber 4, wherein the process chamber 4 is provided with an air inlet 401, an air outlet 402, an upper heating device 5, a lower heating device 6 and a wafer heating treatment table, wherein the wafer heating treatment table is arranged between the upper heating device 5 and the lower heating device 6; the wafer heating treatment table is communicated with the air inlet 401 and the air outlet 402, and is isolated from the airflow of the upper heating device 5 and the lower heating device 6; the wafer heating treatment table is sequentially provided with an air floating drive mechanism 10 and a turntable 8 in the direction from the lower heating device 6 to the upper heating device 5, wherein the turntable 8 is arranged above the air floating drive mechanism 10, and is connected to the lower heating device 6 through a rotating shaft 9, and the air floating drive mechanism 10 can drive the turntable 8 to be in an air floating state and rotate relative to the rotating shaft 9.

[0057] In this embodiment, the process chamber 4 is provided with an air inlet 401 and an air outlet 402, the purpose of which is to balance the pressure difference inside and outside the process chamber 4 and ensure the safety of the rapid thermal processing process. The utility model does not make specific requirements on the gas entering and exiting the process chamber 4, as long as it does not have an adverse effect on the rapid thermal processing process, such as inert gas or nitrogen, etc. In one embodiment, the gas entering and exiting the process chamber 4 is preferably nitrogen.

[0058] The purpose of isolating the airflow between the wafer heating treatment table and the upper heating device 5 and the lower heating device 6 is to prevent the gas entering and leaving the process chamber 4 from entering the upper heating device 5 and the lower heating device 6, thereby reducing the heat source temperature of the upper heating device 5 and the lower heating device 6.

[0059] The present embodiment does not impose any specific limitation on the types of heating sources of the lower heating device 6 and the upper heating device 5 , as long as they can heat the wafer on the wafer heating processing table, such as a halogen tungsten lamp.

[0060] In order to achieve airflow isolation between the wafer heating treatment table and the upper heating device 5 and the lower heating device 6, as an embodiment, an upper transparent quartz window 502 and a lower transparent quartz window 602 are respectively arranged at the positions of the upper heating device 5 and the lower heating device 6 facing the wafer heating treatment table, the upper transparent quartz window 502 seals the upper heating source 501 of the upper heating device 5 in the upper end space of the process chamber 4, and the lower transparent quartz window 602 seals the lower heating source 601 of the lower heating device 6 in the lower end space of the process chamber 4, and the upper transparent quartz window 502 and the lower transparent quartz window 602 are between the upper transparent quartz window 502 and the lower transparent quartz window 602 for the installation space of the wafer heating treatment table, and the air inlet 401 and the air outlet 402 are connected in the installation space, thereby achieving airflow isolation between the wafer heating treatment table and the upper heating device 5 and the lower heating device 6. Since the upper transparent quartz window 502 and the lower transparent quartz window 602 are both made of transparent quartz, they can not only ensure that the wafer heating treatment table is isolated from the airflow of the upper heating device 5 and the lower heating device 6 respectively, but also facilitate the light emitted by the upper heating source 501 and the lower heating source 601 to enter the wafer heating treatment table, prevent the formation of cold spots on the wafer, and ensure the uniformity of heating of the wafer.

[0061] The wafer heating processing table is sequentially provided with an air floating drive mechanism 10 and a turntable 8 in the direction from the lower heating device 6 to the upper heating device 5. The air floating drive mechanism 10 is provided on the lower transparent quartz window 602. The turntable 8 is provided above the air floating drive mechanism 10 and is connected to the lower transparent quartz window 602 through a rotating shaft 9. The air floating drive mechanism 10 can drive the turntable 8 to be in an air floating state and rotate relative to the rotating shaft 9.

[0062] The air-floating drive mechanism 10 is a mature technology in the art. Therefore, the present invention does not limit the specific structure of the air-floating drive mechanism 10 and can be set according to actual use requirements.

[0063] As an example, please refer to Figure 4 and Figure 5 The air-floating drive mechanism 10 is provided with at least three first air-floating stators 1001, which are used to stably float the turntable 8 in a plane, so as to reduce the friction between the turntable 8 and the components below it, such as the air-floating drive mechanism 10. Specifically, the first air-floating stator 1001 is provided with a first air blowing port vertically facing the turntable 8, and the first air blowing port is connected to the air-floating gas supply device through a first air supply pipe 1005. The air-floating gas supply device delivers a vertical airflow to the back of the turntable 8 through the first air blowing port, so that the turntable 8 is stably floated in a horizontal plane.

[0064] Since in the rapid thermal treatment process, it is necessary to drive the wafer to rotate at a high speed to achieve uniform heating of the wafer. Therefore, further, the air-floating drive mechanism 10 is also provided with a second air-floating stator 1002, through which a certain pressure of air flow is delivered to the back of the turntable 8 to drive the turntable 8 to accelerate or maintain at a preset rotation rate. Specifically, the second air-floating stator 1002 is provided with a second air blowing port inclined toward the turntable 8, and the second air blowing port is connected to the air-floating gas supply device through a second air supply pipe 1006. The air-floating gas supply device delivers an air flow to the turntable 8 through the second air blowing port to make the turntable 8 rotate in the first direction, with the purpose of driving the turntable 8 to accelerate or maintain at a preset rotation rate. In this embodiment, the second air blowing port is inclined at a certain angle relative to the vertical direction, and it is ensured that the air flow blown out from the second air blowing port can act on the turntable 8, thereby making the turntable 8 rotate in the first direction.

[0065] After the process is completed, the rotating wafer needs to be decelerated until it stops rotating. Therefore, further, the air flotation drive mechanism 10 is also provided with a third air flotation stator 1003, through which a certain pressure of air flow is delivered to the back of the turntable 8 to decelerate the rotating turntable 8. Specifically, the third air flotation stator 1003 is provided with a third blowing port inclined toward the turntable 8, and the third blowing port is in the opposite direction of the inclination of the second blowing port. The third blowing port is connected to the air flotation gas supply device through the third air supply pipe 1004. The air flotation gas supply device delivers an air flow to the turntable 8 through the third blowing port to make the turntable 8 rotate in the opposite direction along the first direction, in order to drive the rotating turntable 8 to decelerate. In this embodiment, the third blowing port is inclined at a certain angle relative to the vertical direction, and it is ensured that the gas blown out from the third blowing port can act on the turntable 8, thereby slowing down the speed of the turntable 8 rotating in the first direction and finally stopping the rotation. Furthermore, the turntable 8 can also rotate in the opposite direction along the first direction through the third air-floating stator 1003 .

[0066] In order to facilitate the light emitted by the upper heating device 5 and the lower heating device 6 to irradiate the wafer, the main body of the air floating drive mechanism 10 and the turntable 8 are preferably made of transparent quartz material, which facilitates the light to irradiate the wafer to heat it and ensures the uniformity of the heating of the wafer.

[0067] In order to further ensure that the gas blown out by the air floating drive mechanism 10 can act on the turntable 8 when the air floating drive mechanism 10 drives the turntable 8, it is preferred that a structure for increasing the surface friction, such as fish scale-like patterns, is provided on the side of the turntable 8 facing the air floating drive mechanism 10, so as to increase the friction between the gas blown out from the air floating drive mechanism 10 and the turntable 8, thereby further improving the working efficiency.

[0068] At least three support columns 7 are provided on the turntable 8 for supporting the wafer 1 in the circumferential direction of the periphery. The present embodiment does not limit the installation structure of the support columns 7 and the turntable 8, and can be set according to actual use requirements. For example, it can be fixed on the surface of the turntable 8; at least three mounting holes can also be provided on the turntable 8, and the lower ends of the support columns 7 are inserted into the corresponding mounting holes, and the upper ends of the support columns 7 are higher than the surface of the turntable 8, in order to prevent the contact between the wafer and the turntable 8, reduce the probability of the back side of the wafer being contaminated and reduce the influence of thermal stress.

[0069] The end of the support column 7 is L-shaped, that is, the end of the support column 7 includes an L-shaped platform 701 and a vertical portion 702. The platform 701 at the L-shaped end is horizontally arranged, and is used to be placed on the edge of the back of the wafer 1 to support the wafer 1; the vertical portion 702 is located at the periphery of the wafer 1, and is used to limit the wafer 1 to prevent the wafer 1 from being relatively displaced with the support column 7 during rotation. Furthermore, the vertical portion 702 is adapted to the peripheral shape of the wafer 1, that is, it is an arc-shaped structure, which further ensures that the wafer 1 does not have a relative displacement with the support column 7 during rotation.

[0070] Since the end of the support column 7 that contacts the wafer 1 is L-shaped, the platform 701 at the L-shaped end is supported on the edge of the wafer, and the vertical part 702 is used to limit the wafer to prevent relative sliding between the support column 7 and the wafer. Therefore, the wear of the support column 7 is very small and does not need to be replaced regularly, resulting in low loss and cost savings.

[0071] Moreover, the contact area between the L-shaped end and the edge of the wafer is increased, and the L-shaped end ensures that the wafer will not collide with other parts due to deviation during rotation, causing the edge of the wafer to be worn and generate particles.

[0072] Furthermore, the wafer includes a peripheral area and a middle area within the peripheral area. Based on this, the utility model supports the support column 7 only on the peripheral circumference of the wafer, and the middle area of ​​the wafer does not contact the support column 7, that is, the middle area of ​​the wafer will not produce a cold spot, please refer to Figure 6 Therefore, the support column 7 will not affect the temperature uniformity inside the wafer, thereby ensuring the temperature uniformity of the wafer.

[0073] Although the utility model is disclosed as above, the utility model is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model. Therefore, the protection scope of the utility model shall be subject to the scope defined by the claims.

Claims

1. A rapid thermal processing device for wafers, characterized in that: The invention comprises a process chamber, wherein the process chamber is provided with an air inlet, an air outlet, an upper heating device, a lower heating device and a wafer heating treatment table; the wafer heating treatment table is arranged between the upper heating device and the lower heating device; the wafer heating treatment table is communicated with the air inlet and the air outlet, and is isolated from the airflow of the upper heating device and the lower heating device; the wafer heating treatment table is provided with an air floating drive mechanism and a turntable in sequence from the lower heating device to the upper heating device, the turntable is arranged above the air floating drive mechanism and is connected to the lower heating device through a rotating shaft, the air floating drive mechanism can drive the turntable to be in an air floating state and rotate relative to the rotating shaft, and the turntable is provided with at least three support columns for supporting the outer circumference of the wafer, the end of the support column is L-shaped, the platform at the L-shaped end is used to place the edge of the wafer, and the vertical part is used to limit the wafer.

2. The rapid thermal processing equipment according to claim 1, characterized in that: The heating sources in the lower heating device and the upper heating device are halogen tungsten lamps.

3. The rapid thermal processing equipment according to claim 2, characterized in that: Transparent quartz windows are arranged at positions of the upper heating device and the lower heating device facing the wafer heating processing station.

4. The rapid thermal processing equipment according to claim 3, characterized in that: The turntable is also made of transparent quartz material, and a surface of the turntable facing the air-floating drive mechanism is provided with fish-scale patterns.

5. The rapid thermal processing equipment according to claim 4, characterized in that: The main body of the air-floating driving mechanism is made of transparent quartz material.

6. The rapid thermal processing equipment according to claim 5, characterized in that: The air-floating drive mechanism is provided with at least three first air-floating stators for stably floating the turntable in a plane.

7. The rapid thermal processing equipment according to claim 6, characterized in that: The air-floating drive mechanism is further provided with a second air-floating stator, through which an airflow with a certain pressure is delivered to the back of the turntable to drive the turntable to accelerate or maintain a preset rotation speed.

8. The rapid thermal processing equipment according to claim 5, characterized in that: The air-floating drive mechanism is further provided with a third air-floating stator, through which an airflow with a certain pressure is delivered to the back of the turntable to decelerate the rotating turntable.

9. The rapid thermal processing equipment according to claim 4, characterized in that: The support column is clamped on the turntable, and the support column is made of transparent quartz material.

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