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CN-117046681-B - Device and method for controlling uniform spraying of center thickness of photosensitive coating on surface of wafer

CN117046681BCN 117046681 BCN117046681 BCN 117046681BCN-117046681-B

Abstract

The invention discloses a device and a method for controlling uniform spraying of the central thickness of a photosensitive coating on the surface of a wafer, which relate to the technical field of wafer processing and have the technical scheme that the device also comprises a processor and a reciprocating telescopic mechanism, wherein the output end of the processor is connected with the input end of a controller, and the output end of the controller is connected with the input end of the reciprocating telescopic mechanism; the device comprises a spray head device, a controller, a processor, a reciprocating telescopic mechanism and a reciprocating telescopic mechanism, wherein the spray head device is used for carrying out spray coating on the wafer surface, the processor is used for generating a driving signal representing the change of spray coating spacing along with time according to the to-be-processed parameters of the wafer to be processed and the actual spray coating parameters of the spray head device, and the reciprocating telescopic mechanism is used for responding to the driving signal transmitted by the controller and then adjusting the spray coating spacing between the spray head device and a bearing table, so that the central thickness of the photosensitive coating on the wafer surface is uniformly sprayed by changing the impact force when the photoresist is sprayed on the surface of the wafer to be processed. The invention effectively weakens the influence of weaker centrifugal force of the center of the wafer to be processed, and can improve the uniformity of 10-20mm in the center area of the wafer, thereby improving the quality of the wafer in the center area.

Inventors

  • LI XIANGHUA
  • Lin Zhongji

Assignees

  • 成都高真科技有限公司

Dates

Publication Date
20260512
Application Date
20220507

Claims (8)

  1. 1. The device for controlling the uniform spraying of the central thickness of the photosensitive coating on the surface of the wafer comprises a bearing table (2), a spray head device (1) and a controller, wherein the controller is used for controlling the bearing table (2) to rotate and controlling the spray head device (1) to spray photoresist on the wafer to be processed on the bearing table (2), and is characterized by further comprising a processor and a reciprocating telescopic mechanism (3), wherein the output end of the processor is connected with the input end of the controller, and the output end of the controller is connected with the input end of the reciprocating telescopic mechanism (3); The processor is used for generating a driving signal representing the change of the spraying interval along with time according to the to-be-processed parameters of the wafer to be processed and the actual spraying parameters of the spray head device (1); the parameters to be processed comprise spraying thickness, spraying range and spraying uniformity, and the actual spraying parameters comprise photoresist viscosity, photoresist concentration, spraying speed and spraying flow; The reciprocating telescopic mechanism (3) is used for responding to a driving signal transmitted by the controller and then adjusting the spraying distance between the spray head device (1) and the bearing table (2), and the central thickness of the photosensitive coating on the surface of the wafer is uniformly sprayed by changing the impact force when the photoresist is sprayed on the surface of the wafer to be processed.
  2. 2. The device for uniformly spraying the central thickness of the photosensitive coating on the surface of the wafer according to claim 1, wherein one reciprocating telescopic mechanism (3) is adopted, and the reciprocating telescopic mechanism (3) is arranged on the bearing table (2) or the spray head device (1) along the vertical direction.
  3. 3. The device for uniformly spraying the central thickness of the photosensitive coating on the surface of the wafer according to claim 1, wherein two reciprocating telescopic mechanisms (3) are adopted, and the two reciprocating telescopic mechanisms (3) are respectively arranged on the bearing table (2) and the spray head device (1) along the vertical direction.
  4. 4. A central thickness uniformity spray control device for a photosensitive coating on a wafer surface according to claim 3, wherein the two reciprocating telescopic mechanisms (3) are synchronously driven in opposite directions or in opposite directions in response to a driving signal.
  5. 5. A central thickness uniformity spray control device for a photosensitive coating on a wafer surface according to claim 3, wherein the driving signal is composed of a first signal and a second signal, one reciprocating telescopic mechanism (3) is driven in response to the first signal, and the other reciprocating telescopic mechanism (3) is driven in response to the second signal.
  6. 6. The control method for uniformly spraying the center thickness of the photosensitive coating on the surface of the wafer is characterized in that the control method is used for the control device for uniformly spraying the center thickness of the photosensitive coating on the surface of the wafer according to any one of claims 1 to 5, and comprises the following steps: the method comprises the steps that a processor generates a driving signal representing the change of a spraying interval along with time according to a to-be-processed parameter of a wafer to be processed and an actual spraying parameter of a spray head device (1), wherein the to-be-processed parameter comprises a spraying thickness, a spraying range and spraying uniformity, and the actual spraying parameter comprises photoresist viscosity, photoresist concentration, spraying speed and spraying flow; The reciprocating telescopic mechanism (3) responds to a driving signal transmitted by the controller and then adjusts the spraying distance between the spray head device (1) and the bearing table (2), and the central thickness of the photosensitive coating on the surface of the wafer is uniformly sprayed by changing the impact force when the photoresist is sprayed on the surface of the wafer to be processed.
  7. 7. The method of claim 6, wherein the frequency information of the driving signal is inversely related to the photoresist thickness and the photoresist concentration, and is positively related to the spraying speed and the spraying flow.
  8. 8. The method of claim 6, wherein the amplitude information of the driving signal is positively correlated with the photoresist thickness, the photoresist concentration, and the spray flow rate, and inversely correlated with the spray speed.

Description

Device and method for controlling uniform spraying of center thickness of photosensitive coating on surface of wafer Technical Field The invention relates to the technical field of wafer processing, in particular to a device and a method for controlling uniform spraying of the center thickness of a photosensitive coating on the surface of a wafer. Background The photolithography process of the semiconductor light guide device generally comprises the procedures of cleaning and drying the surface of a wafer, priming, spin coating photoresist, soft baking, aligning exposure, post baking, developing, hard baking, etching, detecting and the like. In spin coating of photoresist, on one hand, the wafer quality is worse than that of 200mm in the central region, and on the other hand, the weak centrifugal force in the central region causes uniformity unevenness, thereby causing abnormal wafer pattern and cd variation, and the photoperiod uniformity of the semiconductor light guide device has the problem that the area diameter of 10-20mm in the central region is uneven, so that the yield of the central region of the wafer is lower than that of 200mm, as shown in fig. 1. When traditional photoresist is sprayed, the spray head device is mainly used for spraying the central area of the alignment wafer, and then the bearing table is controlled to rotate so as to uniformly coat the photoresist under the action of centrifugal force. In order to overcome the problem of non-uniformity in the central area of the wafer, it has been described that by controlling the nozzle device to swing left and right in the vertical plane, the photoresist can be distributed more evenly along the entire radial direction of the wafer during the ejection. However, since the susceptor is in a rotating state during photoresist spraying, the uniformity of the distribution of the photoresist in the circumferential direction during spraying is poor compared with that during direct spraying from the center, the amount of the photoresist in the unit time needs to be adjusted and the rotation time of the susceptor needs to be prolonged. Therefore, how to study and design a device and a method for uniformly spraying the center thickness of the photosensitive coating on the surface of the wafer, which can overcome the defects, is an urgent problem to be solved at present. Disclosure of Invention In order to solve the defects in the prior art, the invention aims to provide the device and the method for uniformly spraying the central thickness of the photosensitive coating on the surface of the wafer, which can improve the uniformity of 10-20mm in the central area of the wafer, thereby improving the quality of the wafer in the central area. The technical aim of the invention is realized by the following technical scheme: In a first aspect, a control device for uniformly spraying the center thickness of a photosensitive coating on the surface of a wafer is provided, and comprises a bearing table, a spray head device, a controller, a processor and a reciprocating telescopic mechanism, wherein the controller is used for controlling the bearing table to rotate and controlling the spray head device to spray photoresist on the wafer to be processed on the bearing table, the output end of the processor is connected with the input end of the controller, and the output end of the controller is connected with the input end of the reciprocating telescopic mechanism; The processor is used for generating a driving signal representing the change of the spraying interval along with time according to the to-be-processed parameters of the wafer to be processed and the actual spraying parameters of the spray head device; The reciprocating telescopic mechanism is used for responding to the driving signal transmitted by the controller and then adjusting the spraying distance between the spray head device and the bearing table, and the central thickness of the photosensitive coating on the surface of the wafer is uniformly sprayed by changing the impact force when the photoresist is sprayed on the surface of the wafer to be processed. Further, the reciprocating telescopic mechanism is arranged on the bearing table or the spray head device along the vertical direction. Furthermore, two reciprocating telescopic mechanisms are adopted, and the two reciprocating telescopic mechanisms are respectively arranged on the bearing table and the spray head device along the vertical direction. Further, the two reciprocating telescopic mechanisms are synchronously driven in opposite directions or in opposite directions after responding to the driving signals. Further, the driving signal is composed of a first signal and a second signal, one reciprocating telescopic mechanism is driven in response to the first signal, and the other reciprocating telescopic mechanism is driven in response to the second signal. In a second aspect, there is provided a control method for uniform spraying of a ce