Diffusion device and method for reducing wafer surface defects

Abstract

The present invention discloses a diffusion device and method for reducing surface defects of wafers, which relates to the field of semiconductor manufacturing technology, and includes a chamber body, a gas circulation mechanism and a transmission mechanism, wherein the gas circulation mechanism is fixedly installed on the right side wall of the chamber body, the height of the gas circulation mechanism is flush with the top of the chamber body, the bottom end of the outer wall of the chamber body is fixedly installed with a transmission mechanism, the horizontal center line of the transmission mechanism coincides with the vertical center line of the chamber body, and the chamber body and the gas circulation mechanism are provided with an intercommunication cavity. The present invention realizes uniform distribution of gas in the chamber through the gas circulation mechanism, solves the problem of impurities in the gas being deposited on the surface of the wafer, and a pure and evenly distributed gas environment helps to reduce impurity deposition and chemical reactions on the surface of the wafer, thereby improving the quality and performance of the wafer.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a diffusion device and method for reducing surface defects of a wafer. Background Art

[0002] Wafers are important materials for manufacturing integrated circuits, and their surface quality directly affects the performance and yield of chips. Devices that reduce the diffusion of defects on the wafer surface play a vital role in the semiconductor manufacturing process. These devices mainly control the environment in which the wafer is located to reduce the diffusion of impurities, particles and other defect sources on the wafer surface.

[0003] In the prior art, the plasma treatment process may introduce new impurities, and the causes of surface defects include uneven air flow, temperature fluctuations and uneven concentration.

[0004] Therefore, it is necessary to propose a diffusion device and method for reducing wafer surface defects in the present application to solve the problems mentioned in the background.

[0005] Patent document CN113707543B discloses a wafer processing method and a wafer processing device. The above patent saves the time of the diffusion machine for wafer processing and improves the efficiency of the furnace tube process for wafer processing, but the above patent cannot achieve uniform distribution of gas in the chamber.

[0006] Patent document CN106356318B discloses a gas distribution diffusion plate and plasma processor. The above patent ensures that the concentration of gas molecules and atomic radicals in the reaction gas involved in wafer processing is basically stable, thereby ensuring the stability of the wafer processing process, and further improving the quality and performance of wafer processing. The stable surface temperature can reduce the risk of solid particles falling on the surface of the processed wafer due to the deposition of reaction byproducts on the surface of the diffusion plate during the process, thereby improving the product yield, but the above patent cannot realize the transportation of wafers inside and outside the device and between different height positions in the chamber.

[0007] Patent document CN102043354B discloses a developing device and a developing method. The above patent realizes that even if the surface of the substrate is highly water-resistant, a developing film can be formed on the entire surface of the substrate, which can reduce development defects. However, the above patent cannot realize the transportation of wafers inside and outside the device and between different height positions in the chamber.

[0008] Patent document CN105185731B discloses a wafer scheduling control method and system for semiconductor heat treatment equipment. The above patent realizes the wafer scheduling management function of semiconductor diffusion equipment that is not equipped with a wafer loading device storage bin, but the above patent cannot realize dual monitoring of gas and wafer surface.

[0009] In summary, the above patents cannot achieve uniform distribution of gas in the chamber, transportation of wafers inside and outside the device and between different height positions in the chamber, fine filtration of impurities in the gas, and dual monitoring of gas and wafer surfaces, resulting in impurities in the gas being deposited on the wafer surface, wafers colliding during transportation, incomplete filtration of complex impurities, and opaque process information;

[0010] To this end, the present application proposes a diffusion device and method for reducing wafer surface defects that can achieve uniform distribution of gas in the chamber, transportation of wafers inside and outside the device and between different height positions in the chamber, fine filtering of impurities in the gas, and dual monitoring of the gas and wafer surfaces. Summary of the invention

[0011] The object of the present invention is to provide a diffusion device and method for reducing wafer surface defects, so as to solve the technical problems raised in the above-mentioned background technology, namely, the inability to achieve uniform distribution of gas in the chamber, transportation of wafers inside and outside the device and between different height positions in the chamber, fine filtering of impurities in the gas and dual monitoring of the gas and wafer surfaces, resulting in impurities in the gas being deposited on the wafer surface, collisions of wafers during transportation, incomplete filtration of complex impurities, and opaque process information.

[0012] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a diffusion device for reducing surface defects of wafers, comprising a chamber body, a gas circulation mechanism and a transmission mechanism, wherein the gas circulation mechanism is fixedly installed on the right side wall of the chamber body, the height of the gas circulation mechanism is flush with the top of the chamber body, the bottom end of the outer wall of the chamber body is fixedly installed with the transmission mechanism, the horizontal center line of the transmission mechanism coincides with the vertical center line of the chamber body, and the chamber body and the gas circulation mechanism are provided with a mutual cavity;

[0013] The gas circulation mechanism includes an air inlet, a gradient filter and an adsorption reaction unit, the air inlet includes an air inlet No. 1 and an air inlet No. 2, the air inlet No. 1 is located directly above the air inlet No. 2, the gas density mass introduced into the air inlet No. 1 is greater than that of the air inlet No. 2, the connecting pipe at the air inlet is configured as a telescoped tube, a gradient filter is fixedly installed inside the telescoped tube, a support tube is sleeved on the outer wall of the telescoped tube, a clamp is arranged inside the support tube, the clamp provides a pre-tightening force to fix the gradient filter, an adsorption reaction unit is fixedly installed on the curved surface where the tail end of the telescoped tube is located, an adsorption subunit is arranged inside the adsorption reaction unit, the adsorption subunit adopts a non-uniform molecular sieve, the molecular sieve is filled with adsorbent, a signal adjustment circuit is integrated on the circuit of the adsorption subunit, and the signal adjustment circuit receives an adsorption start signal transmitted by a control center.

[0014] Preferably, a clamping structure is fixedly installed at the top of the outer wall of the transmission mechanism, the transmission mechanism includes a circulation chamber, a lifting bucket and a No. 2 tray, a lifting bucket is arranged inside the circulation chamber, an electric push rod is fixedly installed at the bottom end of the inner wall of the lifting bucket, the No. 2 tray is fixedly installed at the bottom end of the outer wall of the circulation chamber, a lifting bucket is fixedly installed at the top of the outer wall of the No. 2 tray, a transition ring is fixedly installed at the top end of the outer wall of the lifting bucket, the circulation chamber is butted with the opening at the bottom of the chamber body, and the piston rod of the electric push rod passes through the bottom of the lifting bucket and is connected to the nut seat;

[0015] A nut seat is fixedly installed on the top of the outer wall of the electric push rod, a bearing seat is fixedly installed on the top of the outer wall of the nut seat, a ball bearing is fixedly installed inside the bearing seat, a hollow partition is set between the turnover cavity and the lifting barrel, and transmission holes are opened on the front of the turnover cavity and the lifting barrel, and the bottom edge of the transmission hole is 100 mm away from the top of the outer wall of pallet No. 2.

[0016] Preferably, a monitoring mechanism is fixedly installed on the front side of the outer wall of the chamber body, an electromagnetic valve is arranged between the monitoring mechanism and the chamber body, the monitoring mechanism comprises a sampling port, an absorption detection unit and an in-situ scanning mirror, a sampling port is opened at the joint between the chamber body and the monitoring mechanism, an absorption detection unit is fixedly installed on the inner wall of a polytetrafluoroethylene pipe connected to the sampling port, an in-situ scanning mirror is fixedly installed on the top of the outer wall of the absorption detection unit, a carrying plate is fixedly installed on the side of the inner wall of the in-situ scanning mirror, a No. 2 positioning plate is fixedly installed on the side of the outer wall of the sample pool, a detection element is fixedly installed on the side of the outer wall of the No. 2 positioning plate, and an exhaust pipe is fixedly installed on the side of the outer wall of the detection element.

[0017] Preferably, the clamping structure includes a chassis, conductive fins and an electrostatic probe, the chassis is fixedly installed on the top of the outer wall of the bearing seat, the conductive fins are fixedly installed on the top of the outer wall of the chassis, the conductive fins are in a ring array, the electrostatic probe is fixedly installed in the middle of the conductive fins, a linear module is fixedly installed on the bottom of the outer wall of the chassis, limit baffles are fixedly installed at both ends of the linear module, the driver of the linear module is connected to the Wi-Fi module, and the Wi-Fi module is wirelessly connected to the remote control terminal.

[0018] Preferably, a throttling element is fixedly installed on the top of the inner wall of the chamber body, a flange is fixedly installed on the bottom of the outer wall of the throttling element, an accelerator is fixedly installed on the bottom of the outer wall of the flange, a nozzle is fixedly installed in the middle of the inner wall of the accelerator, and a fixing frame is fixedly installed on the top of the outer wall of the throttling element;

[0019] A main air guide plate is fixedly installed on the side surface of the outer wall of the accelerator, and a secondary air guide plate is fixedly installed on the other end of the side surface of the outer wall of the accelerator.

[0020] Preferably, a lower base is fixedly installed on the edge of the outer wall of the chassis, a carrying plate is fixedly installed on the top of the outer wall of the lower base, the edge of the carrying plate is set as an arc guide angle, a magnetic sheet is fixedly installed on the side of the inner wall of the carrying plate, an upper base is fixedly installed on the top of the outer wall of the carrying plate, a positioning pin is arranged between the upper base and the lower base, a cover plate is fixedly installed on the top of the outer wall of the turnover cavity, and a No. 1 tray is fixedly installed on the bottom end of the outer wall of the lower base.

[0021] Preferably, a metal substrate is laid at the bottom of the conductive fin, the metal substrate is connected to direct current, and a buffer pad is fixedly installed on the contact surface between the conductive fin and the wafer;

[0022] The metal substrate is grounded through a wire, the electrostatic probe is connected to the electrostatic neutralizer, the contact surfaces of the turnover cavity, the lifting bucket and the chassis are provided with conductive rubber gaskets, and the lead pins on the side of the chassis are connected to the grounding wire of the metal substrate.

[0023] Preferably, the absorption detection unit includes a sample pool, a light-emitting element and a detection element. The sample pool is fixedly installed on the outer wall side of the detection element. The light-emitting element is fixedly installed on the outer wall side of the sample pool. A positioning plate is fixedly installed on the outer wall side of the light-emitting element. The detection element transmits electrical signals through a data line connected to a signal processing circuit based on optical principles.

[0024] Preferably, S1, first, place the wafer on the second tray and align it with the upper base and the lower base through positioning pins;

[0025] S2, the signal conditioning circuit receives the adsorption start signal transmitted by the control center, pre-treats the wafer surface, and uses low-temperature plasma to remove particulate contamination and chemical residues on the wafer surface;

[0026] S3. Introduce gases of different densities and masses through the No. 1 and No. 2 inlets. The gradient filter in the stacked tube performs multi-stage filtration on the incoming gas. The non-uniform molecular sieve and adsorbent in the adsorption reaction unit further purify the gas by utilizing the physical and chemical properties of the substance itself.

[0027] S4. The multi-layer airflow distribution system and temperature sensor monitor the airflow distribution in the circulation chamber and transmit signals to the control center. The control center feeds back and adjusts the temperature and airflow distribution in the chamber. The treated gas enters the chamber body through the interconnected cavity. The throttling element at the top of the inner wall of the chamber body performs preliminary throttling on the gas. Then the gas enters the accelerator through the flange. The nozzle in the accelerator accelerates the gas to spray out. At the same time, the main air guide plate and the auxiliary air guide plate guide the airflow direction.

[0028] S5. Open the solenoid valve between the monitoring mechanism and the chamber body. The gas in the chamber body enters the polytetrafluoroethylene pipe through the sampling port and passes through the absorption detection unit. The light emitting element emits light. The light passes through the gas sample in the sample pool. The detection element detects the change of light based on optical principles, and the in-situ scanning mirror scans the wafer surface.

[0029] Preferably, S11, connect the linear module to the remote control terminal through the Wi-Fi module, debug the linear module, control the lifting of the lifting bucket by the electric push rod, use the transmission hole to transport the wafer from the outside to the No. 2 tray in the turnover cavity, operate the electric push rod again, adjust the height of the lifting bucket, use the electrostatic probe in the middle of the conductive fin to electrostatically adsorb the wafer, and at the same time, connect the bottom of the conductive fin to a metal substrate with direct current for auxiliary fixation, and use a buffer pad to prevent damage to the wafer surface.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention realizes uniform distribution of gas in the chamber through the gas circulation mechanism, solves the problem of impurities in the gas being deposited on the surface of the wafer, and the pure and uniformly distributed gas environment helps to reduce impurity deposition and chemical reactions on the surface of the wafer, thereby improving the quality and performance of the wafer;

[0032] 2. The present invention realizes the transportation of wafers inside and outside the device and between different height positions in the chamber through the transmission mechanism, solves the problem of wafer collision during transportation, and the efficient and safe transportation and precise positioning and fixing method make the conversion of wafers between different process links faster;

[0033] 3. The present invention uses a gradient filter to achieve fine filtration of impurities in the gas, solves the problem of incomplete filtration of complex impurities, improves the purity of the gas, and reduces the risk of corrosion and clogging of equipment by impurities;

[0034] 4. The present invention realizes dual monitoring of gas and wafer surface through the monitoring mechanism, solves the problem of opaque process information, timely discovers wafer surface defects and takes measures to reduce the scrap rate caused by surface defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a front view structural schematic diagram of the present invention;

[0036] Figure 2 It is a schematic diagram of the gas circulation mechanism structure of the present invention;

[0037] Figure 3 It is a schematic diagram of the transmission mechanism structure of the present invention;

[0038] Figure 4It is a schematic diagram of the structure of the gradient filter of the present invention;

[0039] Figure 5 It is a schematic diagram of the structure of the monitoring mechanism of the present invention;

[0040] Figure 6 It is a schematic diagram of the clamping structure of the present invention;

[0041] Figure 7 It is a schematic diagram of the linear module structure of the present invention;

[0042] Figure 8 It is a schematic diagram of the structure of the adsorption reaction unit of the present invention.

[0043] In the figure: 1. Chamber body; 2. No. 1 air inlet; 3. Gradient filter; 4. Adsorption reaction unit; 5. Cover plate; 6. No. 1 tray; 7. Positioning pin; 8. Carrying plate; 9. No. 2 air inlet; 10. Conductive fin; 11. Electrostatic probe; 12. Buffer pad; 13. Magnetic sheet; 14. Overlap tube; 15. Support tube; 16. No. 1 positioning plate; 17. No. 2 positioning plate; 18. Turnover chamber; 19. No. 2 tray; 20. Lifting bucket; 2 1. Transition ring; 22. Nut seat; 23. Bearing seat; 24. Linear module; 25. Chassis; 26. Limit baffle; 27. Metal substrate; 28. Lower base; 29. ​​Upper base; 30. Sample pool; 31. In-situ scanning mirror; 32. Throttling element; 33. Exhaust pipe; 34. Auxiliary air guide plate; 35. Light-emitting element; 36. Detection element; 37. Flange; 38. Accelerator; 39. Nozzle; 40. Fixed frame; 41. Main air guide plate. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] See also Figure 1-Figure 8 , an embodiment provided by the present invention: a diffusion device for reducing surface defects of wafers, comprising a chamber body 1, a gas circulation mechanism and a transmission mechanism, wherein the gas circulation mechanism is fixedly mounted on the right side wall of the chamber body 1, the height of the gas circulation mechanism is flush with the top of the chamber body 1, the transmission mechanism is fixedly mounted on the bottom end of the outer wall of the chamber body 1, the horizontal center line of the transmission mechanism coincides with the vertical center line of the chamber body 1, and the chamber body 1 and the gas circulation mechanism are provided with an intercommunication cavity;

[0048] The method of use comprises the following steps: S1, first, placing the wafer on the second tray 19, and aligning it with the upper base 29 and the lower base 28 through the positioning pins 7;

[0049] S2, the signal conditioning circuit receives the adsorption start signal transmitted by the control center, pre-treats the wafer surface, and uses low-temperature plasma to remove particulate contamination and chemical residues on the wafer surface;

[0050] S3, introducing gases of different densities and masses through the first gas inlet 2 and the second gas inlet 9, the gradient filter 3 in the stacked tube 14 performs multi-stage filtration on the incoming gas, and the non-uniform molecular sieve and adsorbent in the adsorption reaction unit 4 further purify the gas by utilizing the physical and chemical properties of the substance itself;

[0051] S4, the multi-layer airflow distribution system and the temperature sensor monitor the airflow distribution of the turnover chamber 18 and transmit the signal to the control center. The control center feeds back and adjusts the temperature and airflow distribution in the chamber. The treated gas enters the chamber body 1 through the interconnected cavity. The throttling element 32 at the top of the inner wall of the chamber body 1 performs preliminary throttling on the gas. Then the gas enters the accelerator 38 through the flange 37. The nozzle 39 in the accelerator 38 accelerates the gas to be ejected. At the same time, the main air guide plate 41 and the auxiliary air guide plate 34 guide the airflow direction.

[0052] S5, open the solenoid valve between the monitoring mechanism and the chamber body 1, the gas in the chamber body 1 enters the polytetrafluoroethylene pipe through the sampling port, passes through the absorption detection unit, the light emitting element 35 emits light, the light passes through the gas sample in the sample pool 30, the detection element 36 detects the change of light based on the optical principle, and the in-situ scanning mirror 31 scans the wafer surface;

[0053] Further, the wafer is placed on the second tray 19, and the positioning pins 7 are aligned with the upper base 29 and the lower base 28. Then, the signal conditioning circuit receives the adsorption start signal from the control center, and pre-treats the surface of the wafer, and the low-temperature plasma technology removes particulate contamination and chemical residues on the surface of the wafer;

[0054] Gas introduction: Gases of different densities and masses are introduced through the first gas inlet 2 and the second gas inlet 9, respectively. Before entering the chamber body 1, the gas first passes through the gradient filter 3 in the stacked tube 14 for multi-stage filtration to preliminarily remove impurities in the gas. Subsequently, the gas enters the adsorption reaction unit 4, where the non-uniform molecular sieve and adsorbent utilize their own physical and chemical properties to further purify the gas.

[0055] The multi-layer airflow distribution system and temperature sensor monitor the airflow distribution in the turnover chamber 18 and transmit signals to the control center. The control center adjusts the temperature and airflow distribution in the chamber according to the data feedback. The processed gas enters the chamber body 1 smoothly through the interconnected cavity. In the chamber body 1, the gas is first throttled at the throttling element 32 at the top of the inner wall, and then enters the accelerator 38 through the flange 37. The nozzle 39 in the accelerator 38 accelerates the gas to eject it. At the same time, the main air guide plate 41 and the auxiliary air guide plate 34 guide the direction of the airflow, so that the gas can act on the wafer surface evenly and stably.

[0056] See also Figure 1 , Figure 2 and Figure 8, an embodiment provided by the present invention: a diffusion device for reducing surface defects of a wafer, the gas circulation mechanism comprising an air inlet, a gradient filter 3 and an adsorption reaction unit 4, the air inlet comprising a No. 1 air inlet 2 and a No. 2 air inlet 9, the No. 1 air inlet 2 is located directly above the No. 2 air inlet 9, the density and mass of the gas introduced into the No. 1 air inlet 2 is greater than that of the No. 2 air inlet 9, the connecting pipe at the air inlet is set as a stacked tube 14, the gradient filter 3 is fixedly installed inside the stacked tube 14, the outer wall of the stacked tube 14 is sleeved with a support tube 15, a card block is arranged inside the support tube 15, the card block provides a pre-tightening force to fix the gradient filter 3, the curved surface where the tail end of the stacked tube 14 is located is fixedly installed with the adsorption reaction unit 4, the adsorption reaction unit 4 is arranged inside an adsorption subunit, the adsorption subunit adopts a non-uniform molecular sieve, the molecular sieve is filled with an adsorbent, the circuit of the adsorption subunit is integrated with a signal adjustment circuit, and the signal adjustment circuit receives an adsorption start signal transmitted by the control center;

[0057] A nut seat 22 is fixedly installed on the top of the outer wall of the electric push rod, a bearing seat 23 is fixedly installed on the top of the outer wall of the nut seat 22, a ball bearing is fixedly installed inside the bearing seat 23, a hollow partition is set between the turnover cavity 18 and the lifting bucket 20, and a transmission hole is opened on the front of the turnover cavity 18 and the lifting bucket 20, and the bottom edge of the transmission hole is 100 mm away from the top of the outer wall of the second tray 19;

[0058] Furthermore, the control center sends an adsorption start signal to the signal conditioning circuit, which then triggers the low-temperature plasma generator, and forms a low-temperature plasma environment on the wafer surface using the glow discharge principle. Based on the principle of fluid dynamics, the No. 1 air inlet 2 is located directly above the No. 2 air inlet 9, and the density of the gas entering is greater than that of the No. 2 air inlet 9, forming a stable stratified airflow structure. From the outer 10μm pore size metal mesh to the inner 0.1μm pore size ceramic membrane, impurities of different particle sizes are graded and filtered based on the screening effect and adsorption effect.

[0059] The support tube 15 provides a pre-tightening force for the gradient filter 3 through the elastic block inside, ensuring that the filter will not be displaced or deformed during the high-speed flow of gas, effectively intercepting more than 95% of the impurity particles with a particle size greater than 0.1 μm in the gas, and the gas after preliminary filtration enters the adsorption reaction unit 4. The adsorption subunit adopts a non-uniform molecular sieve with a micro-channel structure to selectively adsorb the target impurity molecules. The molecular sieve is filled with an adsorbent based on a metal organic framework material, which uses its high specific surface area and abundant active sites to further remove trace impurities in the gas through a combination of physical adsorption and chemical adsorption;

[0060] The signal conditioning circuit adjusts the working parameters of the adsorption subunit, such as temperature and electric field strength, according to the instructions of the control center. After purification, the impurity concentration in the gas is reduced to below 1ppm.

[0061] See also Figure 1 , Figure 5 and Figure 7 , an embodiment of the present invention: a diffusion device for reducing surface defects of a wafer, wherein a monitoring mechanism is fixedly installed on the front of the outer wall of the chamber body 1, an electromagnetic valve is arranged between the monitoring mechanism and the chamber body 1, the monitoring mechanism comprises a sampling port, an absorption detection unit and an in-situ scanning mirror 31, a sampling port is provided at the joint between the chamber body 1 and the monitoring mechanism, an absorption detection unit is fixedly installed on the inner wall of a polytetrafluoroethylene pipe connected to the sampling port, an in-situ scanning mirror 31 is fixedly installed on the top of the outer wall of the absorption detection unit, a carrier plate 8 is fixedly installed on the side of the inner wall of the in-situ scanning mirror 31, a second positioning plate 17 is fixedly installed on the side of the outer wall of the sample pool 30, a detection element 36 is fixedly installed on the side of the outer wall of the second positioning plate 17, and an exhaust pipe 33 is fixedly installed on the side of the outer wall of the detection element 36;

[0062] A throttling element 32 is fixedly mounted on the top of the inner wall of the chamber body 1, a flange 37 is fixedly mounted on the bottom of the outer wall of the throttling element 32, an accelerator 38 is fixedly mounted on the bottom of the outer wall of the flange 37, a nozzle 39 is fixedly mounted in the middle of the inner wall of the accelerator 38, and a fixing frame 40 is fixedly mounted on the top of the outer wall of the throttling element 32; a main air guide plate 41 is fixedly mounted on the side of the outer wall of the accelerator 38, and a secondary air guide plate 34 is fixedly mounted on the other end of the side of the outer wall of the accelerator 38;

[0063] The method of use further includes the following steps: S11, connecting the linear module 24 to the remote control terminal through the Wi-Fi module, debugging the linear module 24, the electric push rod controlling the lifting and lowering of the lifting bucket 20, using the transmission hole to transport the wafer from the outside to the No. 2 tray 19 in the turnover cavity 18, operating the electric push rod again, adjusting the height of the lifting bucket 20, using the electrostatic probe 11 in the middle of the conductive fin 10 to electrostatically adsorb the wafer, and at the same time connecting the metal substrate 27 with direct current at the bottom of the conductive fin 10 to assist in fixing, and the buffer pad 12 prevents damage to the wafer surface;

[0064] Further, the wafer is transported from the outside to the No. 2 tray 19 in the turnover cavity 18 through the transmission hole. After that, the electric push rod is operated again to adjust the height of the lifting barrel 20. The electrostatic probe 11 in the middle of the conductive fin 10 induces opposite charges on the surface of the wafer based on the principle of electrostatic adsorption, thereby electrostatically adsorbing the wafer. At the same time, the metal substrate 27 connected to direct current at the bottom of the conductive fin 10 provides additional auxiliary fixation for the wafer. The buffer pad 12 is made of polytetrafluoroethylene polymer material to buffer the impact force on the wafer surface that may be caused by electrostatic adsorption or other external forces.

[0065] The purified gas enters the chamber body 1 through the interconnected cavity. At the top of the inner wall of the chamber body 1, the throttling element 32 performs preliminary throttling on the gas based on the Bernoulli principle, stabilizes the airflow pressure, and reduces the fluctuation of the airflow speed. The throttling element 32 is tightly connected to the upper fixed frame 40. Then, the gas enters the accelerator 38 through the flange 37. The nozzle 39 in the accelerator 38 adopts a Laval nozzle structure design. According to the principle of gas dynamics, the gas is accelerated to a supersonic state and ejected by controlling the size of the contraction section and the expansion section of the nozzle. At the same time, the main guide plate 41 and the auxiliary guide plate 34 on the side of the outer wall of the accelerator 38 guide the high-speed airflow according to the streamlined design principle in aerodynamics, ensuring that the airflow hits the wafer surface at a uniform angle and speed, achieving uniform deposition of diffused substances on the wafer surface, and effectively avoiding wafer surface defects caused by uneven airflow.

[0066] See also Figure 1 , Figure 3 and Figure 6 , an embodiment of the present invention provides: a diffusion device for reducing surface defects of wafers, wherein a clamping structure is fixedly installed on the top of the outer wall of the transmission mechanism, the transmission mechanism comprises a circulation chamber 18, a lifting bucket 20 and a No. 2 tray 19, a lifting bucket 20 is arranged inside the circulation chamber 18, an electric push rod is fixedly installed on the bottom end of the inner wall of the lifting bucket 20, a No. 2 tray 19 is fixedly installed on the bottom end of the outer wall of the circulation chamber 18, a lifting bucket 20 is fixedly installed on the top end of the outer wall of the No. 2 tray 19, a transition ring 21 is fixedly installed on the top end of the outer wall of the lifting bucket 20, the circulation chamber 18 is docked with the opening at the bottom of the chamber body 1, and the piston rod of the electric push rod passes through the bottom of the lifting bucket 20 and is connected to the nut seat 22;

[0067] The bottom plate 25 is fixedly mounted with a lower base 28 on the outer wall edge, a carrier plate 8 is fixedly mounted on the outer wall top of the lower base 28, the edge of the carrier plate 8 is set as an arc chamfer, a magnetic sheet 13 is fixedly mounted on the inner wall side of the carrier plate 8, an upper base 29 is fixedly mounted on the outer wall top of the carrier plate 8, a positioning pin 7 is arranged between the upper base 29 and the lower base 28, a cover plate 5 is fixedly mounted on the outer wall top of the turnover cavity 18, and a No. 1 tray 6 is fixedly mounted on the outer wall bottom of the lower base 28;

[0068] Furthermore, the lifting bucket 20 inside the turnover chamber 18 controls the wafer lifting and lowering through the electric push rod installed at the bottom. The driving motor of the electric push rod has a closed-loop control system. The height of the lifting bucket 20 is adjusted according to the preset instructions. The positioning accuracy can reach ±0.05mm. The wafer is sent into the turnover chamber 18 by the external handling equipment through the No. 2 tray 19. The top of the outer wall of the No. 2 tray 19 is tightly connected with the lifting bucket 20. When the wafer is placed on the No. 2 tray 19, the electric push rod is operated to make the lifting bucket 20 rise. The transition ring 21 guides and buffers the height of the lifting bucket 20. When the lifting bucket 20 rises to dock with the opening at the bottom of the chamber body 1, the cover plate 5 at the top of the outer wall of the turnover chamber 18 is automatically closed to form a closed environment.

[0069] During the diffusion process, the solenoid valve between the monitoring mechanism and the chamber body 1 is opened, and the gas in the chamber body 1 enters the polytetrafluoroethylene pipe through the sampling port. The absorption detection unit fixedly installed on the inner wall of the pipe detects specific components in the gas based on the principle of molecular absorption spectroscopy. The light emitting element 35 emits light, and when the light passes through the gas sample in the sample pool 30, it interacts with the gas molecules. The detection element 36 detects the light changes based on the Lambert-Beer law, inverts the gas composition and concentration changes, and transmits the data to the control system in real time.

[0070] See also Figure 1 , Figure 4 and Figure 7 , an embodiment of the present invention provides: a diffusion device for reducing surface defects of a wafer, the clamping structure comprises a chassis 25, a conductive fin 10 and an electrostatic probe 11, the chassis 25 is fixedly mounted on the top of the outer wall of the bearing seat 23, the conductive fin 10 is fixedly mounted on the top of the outer wall of the chassis 25, the conductive fin 10 is in a ring array, the electrostatic probe 11 is fixedly mounted in the middle of the conductive fin 10, a linear module 24 is fixedly mounted on the bottom of the outer wall of the chassis 25, and limited baffles 26 are fixedly mounted at both ends of the linear module 24, the driver of the linear module 24 is connected to the Wi-Fi module, and the Wi-Fi module is wirelessly connected to the remote control terminal;

[0071] The bottom of the conductive fin 10 is paved with a metal substrate 27, the metal substrate 27 is connected to direct current, and a buffer pad 12 is fixedly installed on the contact surface between the conductive fin 10 and the wafer;

[0072] The metal substrate 27 is grounded through a wire, the electrostatic probe 11 is connected to the electrostatic neutralizer, the contact surfaces of the turnover cavity 18, the lifting bucket 20 and the chassis 25 are provided with conductive rubber gaskets, and the side lead pins of the chassis 25 are connected to the ground wire of the metal substrate 27;

[0073] The absorption detection unit includes a sample pool 30, a light emitting element 35 and a detection element 36. The sample pool 30 is fixedly mounted on the outer wall side of the detection element 36. The light emitting element 35 is fixedly mounted on the outer wall side of the sample pool 30. A first positioning plate 16 is fixedly mounted on the outer wall side of the light emitting element 35. The detection element 36 transmits electrical signals through a data line connected to a signal processing circuit based on an optical principle;

[0074] Furthermore, the light emitting element 35 emits light, and the light passes through the gas sample in the sample pool 30 and interacts with the gas molecules, causing the light intensity and wavelength to change. The detection element 36 detects the change of the light based on the Lambert-Beer law, and converts the detected light signal into an electrical signal, which is transmitted to the signal processing circuit through the data line. After the signal processing circuit performs a series of processing such as amplification, filtering, analog-to-digital conversion, etc. on the electrical signal, it inverts the gas composition and concentration changes, and transmits the data to the control system in real time;

[0075] The No. 1 positioning plate 16 on the side of the outer wall of the sample pool 30 provides positioning for the light-emitting element 35. The detection element 36 is based on optical sensor technology to realize real-time monitoring of changes in gas component concentrations. The in-situ scanning mirror 31 uses atomic force microscopy technology to perform real-time scanning of the wafer surface with nanometer-level resolution. It is installed on the top of the outer wall of the absorption detection unit and stably supports the wafer through the carrier plate 8. During the scanning process, the weak interaction force between the AFM probe and the atoms on the wafer surface is measured to obtain the microscopic morphology information of the wafer surface. Once defects such as scratches, pits or impurity particles are detected on the wafer surface, the system immediately feeds back the defect information to the control system. The control system adjusts the process parameters in real time according to the process standards and algorithms, and adjusts the gas flow, temperature, and air flow speed for correction. At the same time, the No. 2 positioning plate 17 on the side of the outer wall of the sample pool 30 provides target positioning for the detection element 36, and the exhaust pipe 33 on the side of the outer wall of the detection element 36 timely discharges the detected gas to maintain the gas flow and pressure balance in the system.

[0076] Working principle: the electric push rod controls the lifting and lowering of the lifting bucket 20, and uses the transmission hole to transport the wafer from the outside to the No. 2 tray 19 in the turnover cavity 18. The electric push rod is operated again to adjust the height of the lifting bucket 20. The linear module 24 is debugged by the remote control terminal through the Wi-Fi module to adjust the position of the conductive fin 10. The electrostatic probe 11 in the middle of the conductive fin 10 electrostatically adsorbs the wafer. At the same time, the metal substrate 27 connected to the direct current at the bottom of the conductive fin 10 assists in fixing. The buffer pad 12 on the contact surface with the wafer prevents damage to the wafer surface. In addition, the arc-shaped chamfer at the edge of the carrier plate 8 protects the wafer surface. The magnetic sheet 13 on the side of the inner wall further fixes the wafer. The upper base 29 and the lower base 28 are aligned through the positioning pin 7.

[0077] According to the physical properties and reaction characteristics of the gas, gases of different densities and masses are introduced from the No. 1 gas inlet 2 and the No. 2 gas inlet 9 located at different positions. The gas is filtered in multiple stages in the stacked tube 14 by a gradient filter 3 composed of multiple layers of filter materials with different pore sizes according to the screening effect and surface adsorption principle to remove impurity particles with a particle size greater than 0.1 μm, making their content less than 0.01 mg / m³, and then enters the adsorption reaction unit 4, where the non-uniform molecular sieve and the adsorbent based on metal organic framework materials use a combination of physical adsorption and chemical adsorption to deeply purify trace impurities in the gas;

[0078] The treated gas enters the chamber body 1 through the interconnected cavity. The throttling element 32 at the top of the inner wall of the chamber body 1 preliminarily throttles the gas based on the Bernoulli principle, stabilizes the airflow pressure, and reduces the speed fluctuation. Then the gas enters the accelerator 38 through the flange 37. The nozzle 39 in the accelerator 38 adopts a Laval nozzle structure design, and accelerates the gas to a supersonic state and ejects it according to the principle of gas dynamics. At the same time, the main air guide plate 41 and the auxiliary air guide plate 34 on the side of the outer wall of the accelerator 38 guide the high-speed airflow according to the streamlined design principle in aerodynamics. The solenoid valve between the monitoring mechanism and the chamber body 1 is opened, and the gas in the chamber body 1 enters the polytetrafluoroethylene pipe through the sampling port. In the absorption detection unit, the light emitting element 35 emits light of a specific wavelength. The light passes through the gas sample in the sample pool 30 and interacts with the gas molecules to cause changes in light intensity and wavelength. The detection element 36 detects light changes in real time based on the Lambert-Beer law through high-precision spectral analysis technology, and converts the light signal into an electrical signal, which is transmitted to the signal processing circuit via the data line, accurately inverts the gas composition and concentration changes, and transmits them to the control system.

[0079] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and range of equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A diffusion device for reducing wafer surface defects, characterized in that: The chamber body (1) comprises a chamber body (1), a gas circulation mechanism and a transmission mechanism, wherein the gas circulation mechanism is fixedly mounted on the right side wall of the chamber body (1), the height of the gas circulation mechanism is flush with the top of the chamber body (1), the transmission mechanism is fixedly mounted on the bottom end of the outer wall of the chamber body (1), the horizontal center line of the transmission mechanism coincides with the vertical center line of the chamber body (1), and the chamber body (1) and the gas circulation mechanism are provided with a mutual cavity; The gas circulation mechanism comprises an air inlet, a gradient filter (3) and an adsorption reaction unit (4), wherein the air inlet comprises a first air inlet (2) and a second air inlet (9), wherein the first air inlet (2) is located directly above the second air inlet (9), the gas density mass introduced into the first air inlet (2) is greater than that of the second air inlet (9), the connecting pipe at the air inlet is arranged as a telescoped tube (14), the gradient filter (3) is fixedly installed inside the telescoped tube (14), the outer wall of the telescoped tube (14) is provided with a support tube (15), a clamping block is arranged inside the support tube (15), the clamping block provides a pre-tightening force to fix the gradient filter (3), the adsorption reaction unit (4) is fixedly installed on the curved surface where the tail end of the telescoped tube (14) is located, the adsorption reaction unit (4) is arranged inside the adsorption reaction unit (4), the adsorption subunit adopts a non-uniform molecular sieve, the molecular sieve is filled with an adsorbent, and the circuit of the adsorption subunit is integrated with a signal adjustment circuit, and the signal adjustment circuit receives an adsorption start signal transmitted by a control center.

2. A diffusion device for reducing wafer surface defects according to claim 1, characterized in that: A clamping structure is fixedly installed at the top of the outer wall of the transmission mechanism, and the transmission mechanism comprises a circulation chamber (18), a lifting bucket (20) and a second tray (19). The lifting bucket (20) is arranged inside the circulation chamber (18), and an electric push rod is fixedly installed at the bottom end of the inner wall of the lifting bucket (20). The second tray (19) is fixedly installed at the bottom end of the outer wall of the circulation chamber (18), and the lifting bucket (20) is fixedly installed at the top of the outer wall of the second tray (19). A transition ring (21) is fixedly installed at the top end of the outer wall of the lifting bucket (20). The circulation chamber (18) is connected to the opening at the bottom of the chamber body (1), and the piston rod of the electric push rod passes through the bottom of the lifting bucket (20) and is connected to the nut seat (22); A nut seat (22) is fixedly installed at the top of the outer wall of the electric push rod, a bearing seat (23) is fixedly installed at the top of the outer wall of the nut seat (22), a ball bearing is fixedly installed inside the bearing seat (23), a hollow partition is set between the turnover cavity (18) and the lifting bucket (20), and a transmission hole is opened on the front of the turnover cavity (18) and the lifting bucket (20), and the bottom edge of the transmission hole is 100 mm away from the top of the outer wall of the second tray (19).

3. A diffusion device for reducing wafer surface defects according to claim 1, characterized in that: A monitoring mechanism is fixedly mounted on the front side of the outer wall of the chamber body (1), a solenoid valve is arranged between the monitoring mechanism and the chamber body (1), the monitoring mechanism comprises a sampling port, an absorption detection unit and an in-situ scanning mirror (31), a sampling port is provided at the joint between the chamber body (1) and the monitoring mechanism, an absorption detection unit is fixedly mounted on the inner wall of a polytetrafluoroethylene pipe connected to the sampling port, an in-situ scanning mirror (31) is fixedly mounted on the top of the outer wall of the absorption detection unit, a carrier plate (8) is fixedly mounted on the inner wall side of the in-situ scanning mirror (31), a second positioning plate (17) is fixedly mounted on the outer wall side of the sample pool (30), a detection element (36) is fixedly mounted on the outer wall side of the second positioning plate (17), and an exhaust pipe (33) is fixedly mounted on the outer wall side of the detection element (36).

4. A diffusion device for reducing wafer surface defects according to claim 2, characterized in that: The clamping structure comprises a chassis (25), a conductive fin (10) and an electrostatic probe (11); the chassis (25) is fixedly mounted on the top of the outer wall of the bearing seat (23); the conductive fin (10) is fixedly mounted on the top of the outer wall of the chassis (25); the conductive fin (10) is arranged in a ring array; the electrostatic probe (11) is fixedly mounted in the middle of the conductive fin (10); a linear module (24) is fixedly mounted on the bottom of the outer wall of the chassis (25); limit baffles (26) are fixedly mounted at both ends of the linear module (24); a driver of the linear module (24) is connected to a Wi-Fi module; and the Wi-Fi module is wirelessly connected to a remote control terminal.

5. The diffusion device for reducing wafer surface defects according to claim 1, characterized in that: A throttling element (32) is fixedly mounted on the top of the inner wall of the chamber body (1); a flange (37) is fixedly mounted on the bottom of the outer wall of the throttling element (32); an accelerator (38) is fixedly mounted on the bottom of the outer wall of the flange (37); a nozzle (39) is fixedly mounted in the middle of the inner wall of the accelerator (38); and a fixing frame (40) is fixedly mounted on the top of the outer wall of the throttling element (32); A main air guide plate (41) is fixedly mounted on the side surface of the outer wall of the accelerator (38), and a secondary air guide plate (34) is fixedly mounted on the other end of the side surface of the outer wall of the accelerator (38).

6. A diffusion device for reducing wafer surface defects according to claim 4, characterized in that: A lower base (28) is fixedly mounted on the edge of the outer wall of the chassis (25); a carrying plate (8) is fixedly mounted on the top of the outer wall of the lower base (28); the edge of the carrying plate (8) is arranged as an arc-shaped chamfer; a magnetic sheet (13) is fixedly mounted on the side of the inner wall of the carrying plate (8); an upper base (29) is fixedly mounted on the top of the outer wall of the carrying plate (8); a positioning pin (7) is arranged between the upper base (29) and the lower base (28); a cover plate (5) is fixedly mounted on the top of the outer wall of the turnover cavity (18); and a No. 1 tray (6) is fixedly mounted on the bottom of the outer wall of the lower base (28).

7. The diffusion device for reducing wafer surface defects according to claim 4, characterized in that: A metal substrate (27) is provided at the bottom end of the conductive fin (10), the metal substrate (27) is connected to direct current, and a buffer pad (12) is fixedly mounted on the contact surface between the conductive fin (10) and the wafer; The metal substrate (27) is grounded via a wire, the static probe (11) is connected to a static neutralizer, the contact surfaces of the turnover cavity (18), the lifting bucket (20) and the chassis (25) are provided with conductive rubber gaskets, and the side lead pins of the chassis (25) are connected to the ground wire of the metal substrate (27).

8. The diffusion device for reducing wafer surface defects according to claim 3, characterized in that: The absorption detection unit comprises a sample pool (30), a light emitting element (35) and a detection element (36); the sample pool (30) is fixedly mounted on the side of the outer wall of the detection element (36); the light emitting element (35) is fixedly mounted on the side of the outer wall of the sample pool (30); a first positioning plate (16) is fixedly mounted on the side of the outer wall of the light emitting element (35); and the detection element (36) transmits an electrical signal by connecting to a signal processing circuit via a data line based on an optical principle.

9. A method for using a diffusion device for reducing wafer surface defects, applicable to a diffusion device for reducing wafer surface defects according to any one of claims 1 to 8, characterized in that: The method of use comprises the following steps: S1. First, place the wafer on the second tray (19) and align it with the upper base (29) and the lower base (28) through the positioning pins (7); S2, the signal conditioning circuit receives the adsorption start signal transmitted by the control center, pre-treats the wafer surface, and uses low-temperature plasma to remove particulate contamination and chemical residues on the wafer surface; S3, introducing gases of different densities and masses through the first gas inlet (2) and the second gas inlet (9), the gradient filter (3) in the stacked tube (14) performs multi-stage filtration on the incoming gas, and the non-uniform molecular sieve and adsorbent in the adsorption reaction unit (4) further purify the gas by utilizing the physical and chemical properties of the substance itself; S4, a multi-layer airflow distribution system and a temperature sensor monitor the airflow distribution of the circulation chamber (18) and transmit a signal to the control center. The control center feedbacks and adjusts the temperature and airflow distribution in the chamber. The treated gas enters the chamber body (1) through the interconnected cavity. The throttling element (32) at the top of the inner wall of the chamber body (1) performs preliminary throttling on the gas. Then, the gas enters the accelerator (38) through the flange (37). The nozzle (39) in the accelerator (38) accelerates the gas to be ejected. At the same time, the main air guide plate (41) and the auxiliary air guide plate (34) guide the airflow direction. S5. Open the solenoid valve between the monitoring mechanism and the chamber body (1). The gas in the chamber body (1) enters the polytetrafluoroethylene pipe through the sampling port and passes through the absorption detection unit. The light emitting element (35) emits light. The light passes through the gas sample in the sample pool (30). The detection element (36) detects the change of the light based on optical principles. The in-situ scanning mirror (31) scans the surface of the wafer.

10. The method for using the diffusion device for reducing wafer surface defects according to claim 9, characterized in that: The method of use also includes the following steps: S11, connect the linear module (24) to the remote control terminal through the Wi-Fi module, debug the linear module (24), control the lifting and lowering of the lifting bucket (20) by the electric push rod, use the transmission hole to transport the wafer from the outside to the No. 2 tray (19) in the turnover cavity (18), operate the electric push rod again, adjust the height of the lifting bucket (20), use the electrostatic probe (11) in the middle of the conductive fin (10) to electrostatically adsorb the wafer, and at the same time, connect the metal substrate (27) with direct current at the bottom of the conductive fin (10) to assist in fixing, and use the buffer pad (12) to prevent damage to the wafer surface.

Images