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CN-115589768-B - Exception handling method for dry etching in aluminum-based superconducting circuit

CN115589768BCN 115589768 BCN115589768 BCN 115589768BCN-115589768-B

Abstract

The invention provides an abnormality processing method for dry etching in an aluminum-based superconducting circuit, which comprises the following steps of (1) providing a sample, (2) heating the sample, etching a slotted exposed aluminum metal layer in a dry etching mode, exposing a dielectric layer in a slotted mode, immediately cleaning the etched sample by deionized water or oxalic acid, drying, etching the slotted exposed dielectric layer in a dry etching mode, (4) sequentially and circularly repeating the step (2) and the step (3) until the slotted exposed aluminum metal layer and the dielectric layer are etched, exposing a substrate, and (5) removing a residual photoresist layer. By adopting the abnormality processing method provided by the invention, the risks of abnormal morphology and blocking after deep groove etching can be effectively avoided in the dry etching process of the aluminum-based superconducting circuit, and the operation is convenient.

Inventors

  • CUI ZHIYUAN
  • XIONG KANGLIN
  • FENG JIAGUI
  • GUO FENG

Assignees

  • 材料科学姑苏实验室

Dates

Publication Date
20260505
Application Date
20221027

Claims (9)

  1. 1. An abnormality processing method of dry etching in an aluminum-based superconducting circuit is characterized by comprising the following steps: (1) Providing a sample: Forming a laminated structure comprising a plurality of aluminum metal layers and a plurality of dielectric layers on one side of a substrate, wherein the aluminum metal layers and the dielectric layers are alternately arranged, and in the laminated structure, the dielectric layer closest to the substrate and the aluminum metal layer farthest from the substrate are formed; Forming a photoresist layer on one side of the laminated structure far away from the substrate, and patterning the photoresist layer, wherein the patterned photoresist layer comprises at least one slot to obtain a sample; (2) Heating a sample, etching the aluminum metal layer exposed by slotting in the step (1) in a dry etching mode, exposing the dielectric layer by slotting, immediately cleaning the etched sample by deionized water or oxalic acid, and drying; (3) Etching the dielectric layer exposed by the grooving in a dry etching mode; (4) Sequentially and circularly repeating the step (2) and the step (3) until the aluminum metal layer and the dielectric layer exposed by the grooves are etched away to expose the substrate; (5) Removing the residual photoresist layer; and (3) cleaning the etched sample by using deionized water or oxalic acid immediately in the step (2), wherein the method specifically comprises the following steps of: The etched samples were immediately rinsed or scrubbed with deionized water 0.5-10.0 min or immediately scrubbed with oxalic acid 0.5-10.0 min.
  2. 2. The exception handling method of claim 1, wherein the heating in step (2) is performed at a temperature of 100-150 ℃ for a time of 2.0-8.0 min.
  3. 3. The anomaly handling method of claim 1, wherein the plurality of aluminum metal layers in step (1) are at least 3 aluminum metal layers, and the plurality of dielectric layers in step (1) are at least 3 dielectric layers.
  4. 4. The abnormality processing method according to claim 1, characterized in that the thickness of each of the plurality of aluminum metal layers in step (1) is each independently 0.06 to 2.0 μm.
  5. 5. The abnormality processing method according to claim 1, characterized in that the thickness of each of the dielectric layers in the step (1) is each independently 0.5 to 5.0 μm.
  6. 6. The anomaly handling method of claim 1, wherein the dielectric layer of step (1) comprises a silicon oxide layer.
  7. 7. The exception handling method according to claim 1, wherein the dry etching gas of step (2) includes Cl 2 and/or BCl 3 .
  8. 8. The abnormality processing method according to claim 1, characterized in that the dry etching gas of step (3) includes CF 4 .
  9. 9. The exception handling method according to any one of claims 1 to 8, characterized in that the exception handling method comprises the steps of: (1) Providing a sample: Forming a laminated structure comprising a plurality of aluminum metal layers and a plurality of dielectric layers on one side of a substrate, wherein the aluminum metal layers and the dielectric layers are alternately arranged, and in the laminated structure, the dielectric layer closest to the substrate and the aluminum metal layer farthest from the substrate are formed; Forming a photoresist layer on one side of the laminated structure far away from the substrate, and patterning the photoresist layer, wherein the patterned photoresist layer comprises at least one slot to obtain a sample; (2) Heating the sample at 100-150 ℃ to 2.0-8.0 min, etching the aluminum metal layer exposed by the grooving in the step (1) by using gas Cl 2 and/or BCl 3 , exposing the dielectric layer by grooving, and then immediately flushing or scrubbing the etched sample by using deionized water to 0.5-10.0 min, or immediately scrubbing the etched sample by using oxalic acid to 0.5-10.0 min, flushing by using deionized water, and drying; (3) Etching the dielectric layer exposed by the grooving by using CF 4 gas; (4) Sequentially and circularly repeating the step (2) and the step (3) until the aluminum metal layer and the dielectric layer exposed by the grooves are etched away to expose the substrate; (5) And removing the residual photoresist layer.

Description

Exception handling method for dry etching in aluminum-based superconducting circuit Technical Field The invention belongs to the technical field of superconducting circuit etching, relates to an abnormality processing method for dry etching in an aluminum-based superconducting circuit, and in particular relates to an abnormality processing method capable of avoiding the occurrence of a column in the dry etching process of the aluminum-based superconducting circuit, thereby avoiding the blocking of a slot. Background In the preparation process of the multi-layer metal wiring of the aluminum-based superconducting circuit, the etching slotting process is particularly complex, a narrow slot needs to be precisely etched, an ideal structure diagram before etching and an ideal structure diagram after etching are respectively shown in fig. 1 and 2, and due to the fact that the depth-to-width ratio is large, and the vertical direction of the slot is a complex film layer structure with 3 pairs or more of overlapped aluminum metal layers and dielectric layers, multiple alternate etching of the aluminum metal layers and the dielectric layers can be involved. Since aluminum oxide particles generated by aluminum corrosion often appear in etching aluminum metal layers, and the aluminum oxide particles act as etching photomasks, when continuing to etch the underlying film layers, high "posts" in the trenches are left in close proximity to the sidewalls due to masking, and in severe cases, the "posts" plug the trenches directly. Accordingly, in the art, it is desirable to develop an abnormality processing method that can avoid the occurrence of "pillars" during dry etching of an aluminum-based superconducting circuit. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide an abnormality processing method for dry etching in an aluminum-based superconducting circuit, in particular to an abnormality processing method which can avoid the occurrence of a column in the dry etching process of the aluminum-based superconducting circuit, thereby avoiding the blocking of a slot. By adopting the abnormality processing method provided by the invention, the occurrence of a column which is higher and is tightly attached to the side wall and is caused by aluminum corrosion and the like in a slot can be avoided in the dry etching process of the aluminum-based superconducting circuit, and the slot is prevented from being blocked. In order to achieve the aim of the invention, the invention adopts the following technical scheme: in a first aspect, the present invention provides an abnormality processing method of dry etching in an aluminum-based superconducting circuit, the abnormality processing method comprising the steps of: (1) Providing a sample: Forming a laminated structure comprising a plurality of aluminum metal layers and a plurality of dielectric layers on one side of a substrate, wherein the aluminum metal layers and the dielectric layers are alternately arranged, and in the laminated structure, the dielectric layer closest to the substrate and the aluminum metal layer farthest from the substrate are formed; Forming a photoresist layer on one side of the laminated structure far away from the substrate, and patterning the photoresist layer, wherein the patterned photoresist layer comprises at least one slot to obtain a sample; (2) Heating a sample, etching the aluminum metal layer exposed by slotting in the step (1) in a dry etching mode, exposing the dielectric layer by slotting, immediately cleaning the etched sample by deionized water or oxalic acid, and drying; (3) Etching the dielectric layer exposed by the grooving in a dry etching mode; (4) Sequentially and circularly repeating the step (2) and the step (3) until the aluminum metal layer and the dielectric layer exposed by the grooves are etched away to expose the substrate; (5) Removing the residual photoresist layer; and (3) cleaning the etched sample by using deionized water or oxalic acid immediately in the step (2), wherein the method specifically comprises the following steps of: The etched sample may be rinsed immediately with deionized water or scrubbed for 0.5-10.0min (e.g., 0.5min, 1min, 1.5min, 2.0min, 2.5min, 3.0min, 3.5min, 4.0min, 5.0min, 6.0min, 7.0min, 8.0min, 9.0min, or 10.0min, etc.), or the etched sample may be scrubbed immediately with oxalic acid for 0.5-10.0min (e.g., 0.5min, 1min, 1.5min, 2.0min, 2.5min, 3.0min, 3.5min, 4.0min, 5.0min, 6.0min, 7.0min, 8.0min, 9.0min, or 10.0min, etc.). In the dry etching process in an aluminum-based superconducting circuit, aluminum oxide particles generated due to aluminum corrosion often appear in etching an aluminum metal layer, and the aluminum oxide particles can serve as etching micro-masks, when the lower film layer is continuously etched, high 'posts' which are closely attached to the side walls are left in the grooves due to shielding effect, and in severe cases, the 'pos