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CN-121992410-A - Liquid separation recovery device and method for double etching process chambers

CN121992410ACN 121992410 ACN121992410 ACN 121992410ACN-121992410-A

Abstract

The invention discloses a liquid separation recovery device and method for double etching process chambers, wherein the device comprises a multi-layer liquid separation assembly, an outer chamber liquid separation CUP, a middle chamber liquid separation CUP and an inner chamber liquid separation CUP which are nested from outside to inside, independent outer chambers, middle chambers and inner chambers are correspondingly communicated below the three-layer liquid separation CUP respectively, a lifting driving mechanism is connected with the outer chambers, the middle chambers and the inner chambers liquid separation CUP respectively and used for independently driving the CUPs of the layers to lift so as to switch a liquid medicine recovery path, a sealing assembly comprises a first sealing ring assembly and a second sealing ring assembly which are arranged at a fixed part of the chambers, the sealing assembly is tightly matched with the corresponding liquid separation CUP to realize sealing isolation among the chambers, and an overflow cleaning mechanism is arranged at the periphery of a carrying disc and used for spraying cleaning liquid at a process switching gap so as to remove residual liquid medicine. The device provided by the invention can realize high recovery rate and low doping rate at any rotation speed, and greatly avoids the pollution problem of different liquid medicine atmospheres in different chambers.

Inventors

  • YANG CHENG
  • ZHOU ZHOU

Assignees

  • 江苏峰博装备技术有限公司

Dates

Publication Date
20260508
Application Date
20260129

Claims (10)

  1. 1. A liquid separation recovery device for a dual etching process chamber, comprising: The multi-layer liquid separation assembly comprises an outer cavity liquid separation CUP (2), a middle cavity liquid separation CUP (3) and an inner cavity liquid separation CUP (4) which are nested from outside to inside, wherein independent outer cavities (9), middle cavities (8) and inner cavities (7) are correspondingly communicated below the three-layer liquid separation CUP respectively; The lifting driving mechanism is respectively connected with the outer cavity, the middle cavity and the inner cavity liquid separating CUP and is used for independently driving each layer of CUP to lift so as to switch the liquid medicine recovery path; The sealing assembly comprises a first sealing ring assembly (10) and a second sealing ring assembly (11) which are arranged at the fixed part of the cavity, and the sealing assembly is tightly matched with the corresponding liquid separation CUP to realize sealing and isolation between the cavities; and the overflow cleaning mechanism (6) is arranged at the periphery of the carrying disc (5) and is used for spraying cleaning liquid at the process switching gap so as to remove residual liquid medicine.
  2. 2. The liquid separating and recovering device for double etching process chambers according to claim 1, wherein the first sealing ring assembly (10) and the second sealing ring assembly (11) have the same structure and are formed by combining a sealing ring with an L-shaped cross section and a sealing ring with a U-shaped cross section.
  3. 3. The liquid separating and recovering device for double etching process chamber of claim 2, wherein when the middle chamber liquid separating CUP (3) or the inner chamber liquid separating CUP (4) is at the descending position, the end parts of the middle chamber liquid separating CUP (3) or the inner chamber liquid separating CUP are simultaneously compressed to form an L-shaped sealing ring and a U-shaped sealing ring, and are matched with the outer end parts of the L-shaped sealing ring and the outer end parts of the U-shaped sealing ring to form bidirectional sealing between the side surfaces and the end surfaces.
  4. 4. A liquid separating and recovering device for a double etching process cavity according to claim 1, wherein a flow guiding channel (17) is arranged at a fixed installation position of the first sealing ring assembly (10) and the second sealing ring assembly (11) and used for guiding a small amount of liquid medicine leaking from a sealing interface to an inner cavity (7) so as to prevent doping among different etching liquids.
  5. 5. The liquid separating and recycling device for double etching process chambers according to claim 1, wherein the overflow cleaning mechanism (6) is annularly arranged and sleeved at the bottom of the carrying tray (5), the liquid separating and recycling device comprises a plurality of water supply interfaces (15) arranged at the bottom end and overflow surfaces (16) obliquely arranged in the radial direction, and each water supply interface (15) is communicated with the overflow surface (16) at the top.
  6. 6. The liquid separation and recovery device for the double etching process cavity according to claim 1, wherein the lifting driving mechanism comprises motors (12) symmetrically arranged on two sides of each CUP and corrugated pipes (13) directly connected with the motors (12), push rods (14) are arranged in the corrugated pipes (13) in a telescopic mode, the tops of the push rods (14) are connected with the inner walls of the corresponding liquid separation CUPs, and the motors (12) drive the push rods (14) to stretch and retract so as to drive the liquid separation CUPs to vertically lift.
  7. 7. A liquid separation and recovery device for a double etching process chamber according to any one of claims 1 to 6, wherein the carrying tray (5) is used for carrying wafers (1) with different sizes, and the device realizes liquid medicine recovery under a static state or any rotating speed by adjusting the height position of each liquid separation CUP.
  8. 8. The liquid separation and recovery device for the double etching process chamber according to claim 1, wherein independent recovery flow passages are respectively arranged at the bottoms of the outer chamber (9), the middle chamber (8) and the inner chamber (7), and controlled switches are arranged at the positions of the flow passages and used for classifying and recovering different liquid medicines.
  9. 9. The liquid separation and recovery device for the double etching process chambers according to claim 1, wherein the middle chamber liquid separation CUP (3) is arranged in the outer chamber liquid separation CUP (9), the inner chamber liquid separation CUP (4) is arranged in the middle chamber liquid separation CUP (3), and gaps for flowing liquid medicine are reserved among the middle chamber liquid separation CUP (3) and the middle chamber liquid separation CUP and the inner chamber liquid separation CUP in the radial direction.
  10. 10. A liquid separation recovery method for a double etching process chamber, using the liquid separation device according to any one of claims 1 to 9, comprising the steps of: Step one, initializing a recovery path, namely driving a push rod (14) to adjust the vertical heights of an outer cavity liquid separation CUP (2), a middle cavity liquid separation CUP (3) and an inner cavity liquid separation CUP (4) through a motor (12) according to the type of liquid medicine to be sprayed, so that the inner wall of a target liquid separation CUP is aligned to a liquid drop throwing path at the edge of a wafer (1); In the first step, if the middle cavity liquid separation CUP (3) or the inner cavity liquid separation CUP (4) is at a descending position where liquid medicine does not need to be collected, the bottom end surface and the side wall of the middle cavity liquid separation CUP are synchronously pressed to form a corresponding first sealing ring assembly (10) or second sealing ring assembly (11), and sealing and blocking of a non-target recovery cavity are realized through compound deformation of an L-shaped sealing ring and a U-shaped sealing ring; Spraying etching liquid or cleaning liquid to the wafer (1), enabling the liquid to enter a target liquid separation CUP under the action of gravity or weak centrifugal force, and enabling the liquid to flow into a corresponding outer chamber (9), middle chamber (8) or inner chamber (7) for classified recovery; in the third step, if a small amount of liquid medicine permeates into the sealing area, the liquid medicine is guided to the inner cavity (7) in a directional way through a guide channel (17) arranged at the fixing position of the sealing assembly so as to prevent the liquid medicine from entering other recovery cavities to cause doping; Step five, process switching cleaning, namely driving all the outer, middle and inner three-layer liquid separation CUPs to rise after the recovery of the current type of liquid medicine and before the switching of the next process liquid medicine, spraying deionized water to the surface of the sealing assembly and the overflow inclined plane through the overflow cleaning mechanism (6), flushing the residual liquid medicine into the inner cavity (7), and completing the online cleaning of the liquid separation path.

Description

Liquid separation recovery device and method for double etching process chambers Technical Field The invention relates to the field of semiconductor manufacturing equipment, in particular to a liquid separation recovery device and method for a double etching process cavity. Background In advanced packaging processes of semiconductors (such as wafer level packaging and 2.5D/3D packaging), precise etching of multi-layer metal wiring structures is a key element for achieving chip miniaturization and high performance. In order to solve the problems of insufficient adhesion and diffusion of copper wiring and a substrate, a copper-titanium composite layer structure, which uses a titanium film as a substrate layer to strengthen adhesion and block copper diffusion, is commonly adopted in the industry, and fine molding of wiring patterns is realized through an etching process. The difference of chemical activities of copper and titanium is remarkable, so that the etching time difference of copper and titanium is huge, the capacity matching of the two processes is difficult, the capacity matching problem can be solved if the two processes are realized in the same cavity at the same time, the capacity can be greatly improved, the etching liquid of copper and titanium also has acid-base difference, and if the chemical reaction of acid and base occurs in the doping of liquid medicine or the doping of atmosphere, the process is influenced. At present, copper and titanium etching is separately carried out in the market, so that doping during recycling is avoided, and the cost and the occupied area are increased. The prior recovery technology mainly relies on a high-rotation-speed spin-drying-collecting tank recovery mode, namely, centrifugal force is generated by high-speed rotation of 2000-5000rpm, so that etching liquid on the surface of a wafer is separated from the collecting tank and is thrown into the side wall of the chamber. However, the technology has the fatal defects in a low-rotation-speed process (such as fine circuit etching needs to be controlled below 500rpm to avoid circuit damage) or a Puddle process (the liquid medicine stays on the surface of a wafer in a liquid film form to realize isothermal etching), namely, firstly, the liquid medicine has insufficient kinetic energy to cause flow disturbance, part of the liquid medicine is adhered to dead corners of a cavity or forms liquid drop splashing, the recovery rate is generally lower than 60 percent and is far lower than the level of more than 90 percent under a high-rotation-speed working condition, secondly, the residual liquid medicine forms a 'cross contamination source' in the cavity, namely, sulfate ions in copper etching liquid react with titanium ions to generate insoluble precipitation if mixed into the titanium etching liquid, so that the etching rate is reduced by more than 30 percent, and fluorine ions in the titanium etching liquid cause hydrogen peroxide decomposition failure if doped into the copper etching liquid, so that the side etching quantity of the circuit exceeds the standard (> 2 mu m), and the yield is reduced to be less than 70 percent. More seriously, existing recovery systems lack an effective mechanism for isolating the fluid. When the etching liquid type is switched in the cavity, residual precursor liquid medicine in the equipment cannot be thoroughly removed, and the residual precursor liquid medicine and newly injected liquid medicine are mixed in the collecting tank, so that the impurity content of the regenerated liquid exceeds the standard to the ppm level, and the multiplexing value is completely lost. Although research is attempted to purify the recovery liquid by an adsorption method or a membrane separation method, the problems of quick saturation of the adsorbent, easy corrosion of the membrane material and the like are solved, so that the purification cost is increased by more than 40%, and the industrialization requirement is difficult to meet. Therefore, how to realize high recovery rate and low cross contamination of etching liquid under the conditions of low rotation speed and Puddle process has become a key technical bottleneck for restricting the control of semiconductor packaging cost and process upgrading. Disclosure of Invention The invention provides a high-precision liquid separation recovery device and method for a double etching process cavity, and aims to solve the problems that when a semiconductor process is cleaned or etched, various liquid medicines are not thoroughly separated, the recovery rate is low, the doping rate is high, and the liquid medicine recovery under the condition of pure or extremely low rotation speed cannot be realized. The invention is realized by the following technical scheme: the invention provides a liquid separation and recovery device for a double etching process chamber, which comprises the following components: The multi-layer liquid separation assembly comprises an o