Structure for excimer ultraviolet cleaning

Abstract

The invention belongs to the technical field of semiconductor equipment, and particularly relates to an excimer ultraviolet cleaning structure which comprises an excimer ultraviolet light source, an irradiation process cavity frame, a liftable wafer bearing table and a sealing ring. And the sealing ring is arranged at the outer edge of the bottom of the liftable wafer bearing table. And the liftable wafer bearing table is driven by the corresponding lifting structure to lift relative to the irradiation process cavity frame. An air inlet channel is formed in the edge of one side of the irradiation process cavity frame, and an exhaust channel is formed in the edge of the other side of the irradiation process cavity frame. According to the invention, excimer ultraviolet cleaning can be effectively carried out on the square substrate, the cleaning rate of organic matter particles is high, and gas discharge is carried out on an irradiation process space defined by the liftable wafer bearing table, the sealing ring, the irradiation process cavity frame and the bottom of the light source shell covering the irradiation process cavity frame during use; the amount of gas needing to be exhausted is greatly reduced, time consumed by cleaning operation is effectively shortened, and the cleaning speed is increased.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor equipment technology, specifically a structure for excimer ultraviolet cleaning. Background Technology

[0002] In the manufacturing process of square substrates in the semiconductor industry, it is necessary to clean the impurity particles on the surface of the square substrates. Currently, the cleaning of square substrates generally uses either pure water cleaning or excimer ultraviolet light source cleaning. Pure water cleaning uses pressurized pure water to impact the surface of the square substrate, thereby removing particles. However, the cleaning rate for organic particles is low. If additional chemical reagents are used, a large amount of chemical reagents are consumed, and secondary pollution may occur. On the other hand, using an excimer ultraviolet light source requires significant time and a low cleaning rate because the square substrate and the conveying structure in the equipment chamber are located in the same interconnected space. During cleaning, a large amount of oxygen in this interconnected space needs to be largely expelled to achieve a sufficiently low oxygen content for subsequent photolysis reactions to achieve photo-cleaning of the square substrate. Summary of the Invention

[0003] To address the above problems, the present invention aims to provide a structure for excimer ultraviolet cleaning.

[0004] The objective of this invention is achieved through the following technical solution: A structure for excimer ultraviolet cleaning includes an excimer ultraviolet light source, the excimer ultraviolet light source includes a light source housing and a light source body, the light source body is disposed in the light source housing, and the bottom of the light source housing is provided with a light-passing window; The structure for excimer ultraviolet cleaning proposed in this invention also includes an irradiation process chamber frame, a height-adjustable substrate stage, and a sealing ring; The outer peripheral surface of the irradiation process cavity frame is fixedly connected to the applicable semiconductor equipment cavity. The middle part of the irradiation process cavity frame is recessed downward to form a basic groove for the process space. A wafer stage receiving opening is opened in the middle of the bottom surface of the basic groove for the process space. The light source housing is disposed on the upper side of the irradiation process cavity frame. The bottom of the light source housing completely covers the basic groove for the process space of the irradiation process cavity frame. The liftable substrate holder is located directly below the frame of the irradiation process cavity. The sealing ring is located at the bottom outer edge of the liftable substrate holder. The size of the outer periphery of the liftable substrate holder is smaller than the size of the substrate holder receiving opening of the irradiation process cavity frame, while the size of the outer periphery of the sealing ring is larger than the size of the substrate holder receiving opening of the irradiation process cavity frame. The liftable substrate holder is raised and lowered by the corresponding lifting structure of the applicable semiconductor equipment. The liftable substrate support is used to support the square substrate during excimer ultraviolet irradiation cleaning. When the square substrate has been supported by the liftable substrate support and is about to undergo excimer ultraviolet irradiation cleaning, the liftable substrate support is lifted by the corresponding lifting structure. The liftable substrate support and the square substrate enter the substrate support receiving port of the irradiation process cavity frame. The sealing ring abuts against the bottom surface of the irradiation process cavity frame and covers the substrate support receiving port of the irradiation process cavity frame. At this time, the liftable substrate support, the sealing ring, the irradiation process cavity frame and the bottom of the light source housing covering the irradiation process cavity frame surround to form the irradiation process space. The light from the light source housing passes through the window and faces the irradiation process space. An air intake channel is provided inside one side edge of the irradiation process chamber frame. Air intake holes are uniformly provided on the inner circumferential surface of the basic groove of the process space of the irradiation process chamber frame, corresponding to the air intake channel. Each air intake hole is connected to the air intake channel. An air intake connector is provided on the outer side surface of the irradiation process chamber frame, connected to the air intake channel and connected to an external inert gas source. An exhaust channel is provided inside the other side edge of the irradiation process chamber frame. Exhaust holes are uniformly provided on the inner circumferential surface of the basic groove of the process space of the irradiation process chamber frame, corresponding to the exhaust channel. Each exhaust hole is connected to the exhaust channel. An exhaust connector is provided on the outer side surface of the irradiation process chamber frame, connected to the exhaust channel and connected to an external negative pressure device. The air intake channel and the exhaust channel are located on opposite sides of the irradiation process chamber frame. Each air intake hole and each exhaust hole on the irradiation process chamber frame is connected to the irradiation process space.

[0005] The top surface of the liftable support platform is provided with several support protrusions, each of which is used to directly support the square substrate, and the top of each support protrusion forms a point contact with the square substrate.

[0006] The liftable support platform is also provided with a number of support pin through holes, each of which is used for a corresponding support pin to pass through.

[0007] The inner circumferential contour of the basic groove of the process space is generally square with rounded corners. The projection of the center point of the basic groove of the process space onto the horizontal plane coincides with the projection of the center point of the receiving opening of the plate stage onto the horizontal plane.

[0008] At least one air inlet hole is also provided at two rounded corners near the air inlet channel on the inner circumferential surface of the basic groove of the process space, and at least one exhaust hole is also provided at the other two rounded corners near the exhaust channel on the inner circumferential surface of the basic groove of the process space.

[0009] On the bottom surface of the basic groove of the process space, an annular guide flange is provided on the outer periphery of the receiving port of the substrate. The top surface of the annular guide flange gradually slopes downward from the inner side near the receiving port of the substrate to the outer side away from the receiving port of the substrate. The projection of the center point of the annular guide flange on the horizontal plane coincides with the projection of the center point of the receiving port of the substrate on the horizontal plane.

[0010] The positions of each air inlet and each air outlet correspond one-to-one.

[0011] The advantages and positive effects of this invention are as follows: This invention can effectively perform excimer ultraviolet cleaning on square substrates, achieving a high cleaning rate for organic particles. During use, only the gas needs to be discharged from the irradiation process space formed by the liftable substrate stage, sealing ring, irradiation process chamber frame, and the bottom of the light source housing covering the irradiation process chamber frame. The amount of gas to be discharged is greatly reduced, effectively reducing cleaning time, increasing cleaning speed, preventing secondary pollution, and the structure is simple and easy to assemble and disassemble. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the irradiation process cavity frame and the liftable plate support stage of the present invention in use. Figure 2 This is a top view schematic diagram of the overall structure of the liftable support platform and sealing ring of the present invention; Figure 3 This is a schematic diagram illustrating the application of the present invention on the applicable semiconductor device.

[0013] In the figure: 1 is the frame of the irradiation process chamber, 101 is the basic groove of the process space, 102 is the air inlet channel, 103 is the air inlet hole, 104 is the exhaust channel, 105 is the exhaust hole, 106 is the annular guide protrusion, 2 is the liftable support platform, 201 is the support PIN needle through hole, 3 is the sealing ring, and 4 is the receiving protrusion. 001 is a square substrate, 002 is a semiconductor device cavity, 003 is a corresponding lifting structure, and 004 is an excimer ultraviolet light source. Detailed Implementation

[0014] The following is in conjunction with the appendix Figures 1-3 The present invention will be described in further detail below.

[0015] A structure for excimer ultraviolet cleaning. Figures 1-3 As shown, this embodiment includes an excimer ultraviolet light source 004, which includes a light source housing and a light source body. The light source body is disposed within the light source housing, and a light-passing window is provided at the bottom of the light source housing. In this embodiment, the excimer ultraviolet light source 004 uses a commercially available 172nm excimer ultraviolet light source product, and its operation is controlled by the control system of the applicable semiconductor device.

[0016] The structure for excimer ultraviolet cleaning in this embodiment also includes an irradiation process chamber frame 1, a liftable substrate stage 2, and a sealing ring 3.

[0017] The outer periphery of the irradiation process cavity frame 1 is fixedly connected to the applicable semiconductor equipment cavity 002. The specific connection method can be any common method as required. A basic process space groove 101 is formed by a downward recess in the middle of the irradiation process cavity frame 1. A wafer stage receiving opening is provided in the middle of the bottom surface of the basic process space groove 101. The light source housing is disposed on the upper side of the irradiation process cavity frame 1, and the bottom of the light source housing completely covers the basic process space groove 101 of the irradiation process cavity frame 1. In this embodiment, the bottom of the light source housing can be sealed and fixedly connected to the irradiation process cavity frame 1 or the semiconductor equipment cavity 002. The connection method adopts existing technology, ensuring a reliable seal between the bottom of the light source housing and the irradiation process cavity frame 1.

[0018] The liftable substrate holder 2 is located directly below the irradiation process chamber frame 1. A sealing ring 3 is positioned at the bottom outer edge of the liftable substrate holder 2. The outer perimeter of the liftable substrate holder 2 is smaller than the perimeter of the substrate holder receiving opening of the irradiation process chamber frame 1, while the outer perimeter of the sealing ring 3 is larger than the perimeter of the substrate holder receiving opening of the irradiation process chamber frame 1. The liftable substrate holder 2 is raised and lowered by the corresponding lifting structure 003 of the applicable semiconductor equipment. In this embodiment, the corresponding lifting structure 003 can be arbitrarily and reasonably designed according to actual needs; for example, a cylinder can be used, and the cylinder's extension and retraction are controlled by the control system of the applicable semiconductor equipment.

[0019] The liftable substrate holder 2 is used to receive the square substrate 001 during excimer ultraviolet irradiation cleaning. When the square substrate 001 has been received by the liftable substrate holder 2 and is about to undergo excimer ultraviolet irradiation cleaning, the liftable substrate holder 2 is lifted by the corresponding lifting structure 003. The liftable substrate holder 2 and the square substrate 001 enter the substrate holder receiving opening of the irradiation process chamber frame 1. The sealing ring 3 abuts against the bottom surface of the irradiation process chamber frame 1 and covers the substrate holder receiving opening of the irradiation process chamber frame 1. At this time, the liftable substrate holder 2, the sealing ring 3, the irradiation process chamber frame 1, and the bottom of the light source housing covering the irradiation process chamber frame 1 surround and form the irradiation process space. The light from the light source housing passes through the window and faces the irradiation process space.

[0020] An air inlet channel 102 is provided inside one side edge of the irradiation process chamber frame 1. Air inlet holes 103 are evenly distributed on the inner circumferential surface of the basic groove 101 of the process space of the irradiation process chamber frame 1, corresponding to the air inlet channel 102. Each air inlet hole 103 is connected to the air inlet channel 102. An air inlet connector connected to the air inlet channel 102 is provided on the outer side surface of the irradiation process chamber frame 1. The air inlet connector is connected to an external inert gas source. An exhaust channel 104 is provided inside the other side edge of the irradiation process chamber frame 1. Exhaust holes 105 are evenly distributed on the inner circumferential surface of the basic groove 101 of the process space, corresponding to the exhaust channel 104. Each exhaust hole 105 is connected to the exhaust channel 104. An exhaust connector connected to the exhaust channel 104 is provided on the outer side of the irradiation process cavity frame 1. The exhaust connector is connected to an external vacuum device. The air inlet channel 102 and the exhaust channel 104 are located on opposite sides of the irradiation process cavity frame 1. Each air inlet hole 103 and each exhaust hole 105 on the irradiation process cavity frame 1 is connected to the irradiation process space. In this embodiment, the air inlet connector and the exhaust connector are both commercially available products. The external inert gas source and the external vacuum device are both set using existing technology. The external inert gas source and the external vacuum device are controlled by the control system of the applicable semiconductor equipment.

[0021] After the liftable substrate holder 2 is lifted by the corresponding lifting structure 003, allowing the liftable substrate holder 2 and the square substrate 001 to enter the substrate holder receiving opening of the irradiation process chamber frame 1, and the sealing ring 3 abuts against the bottom surface of the irradiation process chamber frame 1 to complete the sealing of the irradiation process space, the external inert gas source and the external vacuum suction device are controlled to start for a predetermined time. At this time, the inert gas enters the irradiation process space evenly through the air inlet channel 102 and each air inlet hole 103. The original oxygen-containing gas in the irradiation process space is discharged through each exhaust. Exhaust is discharged through holes 105 and exhaust channels 104. The size of the airflow in the irradiation process space must not cause the square substrate 001 to move. After the oxygen content in the irradiation process space is reduced to a certain level, the excimer ultraviolet light source 004 is controlled to work. The emitted ultraviolet light causes the gas in the irradiation process space to undergo a photolysis reaction, breaking the chemical bonds in the molecules of organic particles on the square substrate 001, causing them to decompose into smaller molecules or directly vaporize. Most particulate impurities can be quickly discharged with the airflow through the exhaust holes 105 and exhaust channels 104. Since only the irradiation process space formed by the liftable substrate stage 2, sealing ring 3, irradiation process chamber frame 1, and the bottom of the light source shell covering the irradiation process chamber frame 1 needs to be vented, the amount of gas to be vented is greatly reduced, effectively reducing the cleaning operation time and increasing the cleaning rate.

[0022] Specifically, such as Figure 2 and Figure 3 As shown, in this embodiment, four receiving protrusions 4 are evenly provided on the top surface of the liftable support stage 2. Each receiving protrusion 4 is used to directly support the square substrate 001. The top of each receiving protrusion 4 forms point contact with the bottom surface of the square substrate 001 at this time. This can minimize the contact area between the receiving protrusion 4 and the square substrate 001 during excimer ultraviolet irradiation cleaning of the square substrate 001, and leave a gap on the lower side of the square substrate 001 to allow gas to pass through, thus removing some particles from the lower side of the square substrate 001. Figure 2 As shown, in this embodiment, the liftable substrate stage 2 is also provided with four support pin through holes 201. Each support pin through hole 201 is used for a corresponding support pin to pass through, and is used in conjunction with the liftable support pin structure of the semiconductor device to facilitate the placement and removal of the square substrate 001 by the liftable substrate stage 2. The outer diameter of the support pin through hole 201 and the corresponding support pin can be made as small as possible, so that it will not have much impact on reducing the oxygen content in the irradiation process space.

[0023] Specifically, such as Figure 2 As shown, in this embodiment, the inner circumferential surface of the basic groove 101 of the process space is generally square with rounded corners. The projection of the center point of the basic groove 101 of the process space onto the horizontal plane coincides with the projection of the center point of the receiving opening of the plate holder onto the horizontal plane. At least one air inlet hole 103 is also provided at two of the rounded corners near the air inlet channel 102 on the inner circumferential surface of the basic groove 101 of the process space, and at the other two rounded corners near the exhaust channel 104 on the inner circumferential surface of the basic groove 101 of the process space. Each air inlet 103 is provided with at least one exhaust port 105, and the positions of each exhaust port 105 correspond one-to-one. An annular guide flange 106 is provided on the bottom surface of the basic groove 101 of the process space and on the outer periphery of the substrate receiving opening. The top surface of the annular guide flange 106 gradually slopes downwards from the inner side near the substrate receiving opening to the outer side away from the substrate receiving opening. The projection of the center point of the annular guide flange 106 onto the horizontal plane coincides with the projection of the center point of the substrate receiving opening onto the horizontal plane. The annular guide flange 106 serves a guiding function. Through the above specific arrangements, the gas flow field within the irradiation process space can be made relatively uniform and stable, avoiding local eddy currents and turbulence, thereby ensuring the cleaning effect on the square substrate 001.

Claims

1. A structure for excimer UV cleaning, comprising an excimer UV light source (004), the excimer UV light source (004) comprising a light source housing and a light source main body, the light source main body being arranged in the light source housing, a light passing window being provided at the bottom of the light source housing; characterized in that Further comprising an irradiation process cavity frame (1), a liftable wafer supporting table (2), and a sealing ring (3); The outer periphery of the irradiation process cavity frame (1) is fixed to a semiconductor device cavity (002) as applicable, a middle portion of the irradiation process cavity frame (1) is concavely arranged to form a process space basic groove (101), a middle portion of the bottom surface of the process space basic groove (101) is provided with a wafer supporting table accommodating opening, the light source housing is arranged on the upper side of the irradiation process cavity frame (1), and the bottom of the light source housing completely covers the process space basic groove (101) of the irradiation process cavity frame (1); The liftable wafer supporting table (2) is located directly below the irradiation process cavity frame (1), the sealing ring (3) is arranged at the outer edge of the bottom of the liftable wafer supporting table (2), the outer periphery of the liftable wafer supporting table (2) is smaller than the size of the contour of the wafer supporting table accommodating opening of the irradiation process cavity frame (1), and the outer periphery of the sealing ring (3) is larger than the size of the contour of the wafer supporting table accommodating opening of the irradiation process cavity frame (1); the liftable wafer supporting table (2) is driven to be lifted by a corresponding lifting structure (003) of the semiconductor device as applicable; The liftable wafer supporting table (2) is used to support a square substrate (001) during excimer UV irradiation cleaning of the square substrate (001); when the square substrate (001) is supported by the liftable wafer supporting table (2) and is to be subjected to excimer UV irradiation cleaning, the liftable wafer supporting table (2) is lifted by the corresponding lifting structure (003), the liftable wafer supporting table (2) and the square substrate (001) jointly enter the wafer supporting table accommodating opening of the irradiation process cavity frame (1), the sealing ring (3) abuts against the bottom surface of the irradiation process cavity frame (1) and covers the wafer supporting table accommodating opening of the irradiation process cavity frame (1), at this time, the liftable wafer supporting table (2), the sealing ring (3), the irradiation process cavity frame (1), and the bottom of the light source housing covering the irradiation process cavity frame (1) surround to form an irradiation process space, and the light passing window of the light source housing faces the irradiation process space; The inner part of one side edge of the irradiation process cavity frame (1) is provided with an air inlet channel (102), the inner circumferential surface of the process space basic groove (101) of the irradiation process cavity frame (1) is uniformly provided with air inlet holes (103) corresponding to the air inlet channel (102), each air inlet hole (103) is communicated with the air inlet channel (102), the outer side surface of the irradiation process cavity frame (1) is provided with an air inlet connector communicated with the air inlet channel (102), the air inlet connector is communicated with an external inert gas source, the inner part of the other side edge of the irradiation process cavity frame (1) is provided with an air outlet channel (104), the inner circumferential surface of the process space basic groove (101) of the irradiation process cavity frame (1) is uniformly provided with air outlet holes (105) corresponding to the air outlet channel (104), each air outlet hole (105) is communicated with the air outlet channel (104), the outer side surface of the irradiation process cavity frame (1) is provided with an air outlet connector communicated with the air outlet channel (104), the air outlet connector is communicated with an external negative pressure extraction device, the air inlet channel (102) and the air outlet channel (104) are respectively located at opposite sides of the whole irradiation process cavity frame (1), and each air inlet hole (103) and each air outlet hole (105) on the irradiation process cavity frame (1) is communicated with the irradiation process space.

2. A structure for excimer UV cleaning according to claim 1, characterized in that: The top surface of the liftable piece supporting table (2) is provided with a plurality of supporting protrusions (4), each of the supporting protrusions (4) is used for directly supporting a square substrate (001), and the top end of each of the supporting protrusions (4) forms a point contact with the square substrate (001).

3. The structure for excimer UV cleaning according to claim 1, wherein: A plurality of PIN supporting through holes (201) are further formed in the liftable piece supporting table (2), and each of the PIN supporting through holes (201) is used for allowing a corresponding PIN to pass through.

4. The structure for excimer UV cleaning according to claim 1, wherein: The inner circumferential surface of the process space basic groove (101) is a square with rounded corners, and the projection of the center point of the process space basic groove (101) on a horizontal plane coincides with the projection of the center point of the piece supporting table accommodating opening on the horizontal plane.

5. A structure for excimer ultraviolet cleaning according to claim 4, wherein: At least one air inlet hole (103) is further formed in each of the two rounded corners of the inner circumferential surface of the process space basic groove (101) close to the air inlet channel (102), and at least one air outlet hole (105) is further formed in each of the other two rounded corners of the inner circumferential surface of the process space basic groove (101) close to the air outlet channel (104).

6. A structure for excimer UV cleaning according to claim 4, wherein: An annular flow guide protrusion (106) is arranged on the bottom surface of the process space basic groove (101) and outside the piece supporting table accommodating opening, the top surface of the annular flow guide protrusion (106) gradually inclines downward from the inner side close to the piece supporting table accommodating opening to the outer side away from the piece supporting table accommodating opening, and the projection of the center point of the annular flow guide protrusion (106) on a horizontal plane coincides with the projection of the center point of the piece supporting table accommodating opening on the horizontal plane.

7. The structure for excimer ultraviolet cleaning according to claim 1, wherein: The setting positions of the gas inlet holes (103) correspond to the setting positions of the gas outlet holes (105) one by one.

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