Continuous preparation method of large-area single-crystal (100) copper foil

Patent metadata

Field	Value
Publication number	US-12448699-B2
Application number	US-202519075353-A
Country	US
Kind code	B2
Filing date	Mar 10, 2025
Priority date	Mar 12, 2024
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

Disclosed is a continuous preparation method of a large-area (100) single-crystal copper foil, a poly-crystal copper foil is connected to a reel-to-reel device, a carbon-based substrate is placed below the copper foil, and the large-area (100) single-crystal copper foil is prepared by applying a stress in a heat treatment process in a reducing/protective atmosphere under an environment with a temperature gradient. According to the invention, the stress is applied to the copper foil for the first time, and strain energy of the copper foil is accurately regulated and controlled, so as to make the strain energy become a main influence factor of grain boundary migration and lattice rotation, so that the strain energy in a growth process of the single-crystal copper foil is controlled to be dominant, and the large-area (100) single-crystal copper foil is controllably prepared through heat treatment in the reducing atmosphere.

First claim

We claim:

1. A continuous preparation method of a large-area (100) single-crystal copper foil, wherein a commercial poly-crystal copper foil is connected to a reel-to-reel device, a carbon-based substrate is placed below the commercial poly-crystal copper foil, strain energy in a growth process of the single-crystal copper foil is controlled to be dominant by applying a stress in a heat treatment process in a reducing/productive atmosphere under an environment with a temperature gradient, so as to make the strain energy become a main influence factor of grain boundary migration and lattice rotation, and then the large-are (100) single-crystal copper foil is prepared; and the preparation method comprises the following steps:
step 1: pretreating the commercial poly-crystal copper foil to remove an organic layer, an oxide layer and impurities;
step 2: connecting the pretreated commercial poly-crystal copper foil to the reel-to-reel device to send the copper foil into a multi-temperature-zone tube furnace, and using the carbon-based substrate placed on a corundum plate or a quartz plate as a support below the commercial poly-crystal copper foil;
step 3: vacuumizing an interior of the multi-temperature-zone tube furnace, and introducing reducing/protecting gas to reach a preset pressure; and
step 4: heating the copper foil under the condition of continuously introducing the reducing/protecting gas until a highest temperature in a center of the copper foil is 980° C. to 1070° C., applying a stress of 80 N to 100 N per square centimeter of cross-sectional area by tightening reels of the reel-to-reel device for 10 minutes to 30 minutes, subjecting the copper foil to heat preservation for 4 hours to 15 hours at the same time, and naturally cooling the copper foil to room temperature, so as to obtain the (100) single-crystal copper foil.

2. The preparation method according to claim 1 , wherein a thickness of the commercial poly-crystal copper foil is 10 μm to 100 μm.

3. The preparation method according to claim 1 , wherein the temperature gradient is 1° C. to 10° C. per centimeter.

4. The preparation method according to claim 1 , wherein a range of the applied stress is 80 N to 100 N per square centimeter of cross-sectional area.

5. The preparation method according to claim 1 , wherein a method of the pretreating in the step 1 comprises soaking the commercial poly-crystal copper foil in dilute sulfuric acid or dilute hydrochloric acid, then washing the copper foil with deionized water and anhydrous ethanol or anhydrous methanol or anhydrous acetone alternately, and drying the copper foil by cold air blowing or dust-free paper suction, wherein a concentration of the dilute sulfuric acid or the dilute hydrochloric acid is 0.2 mol/L to 1 mol/L.

6. The preparation method according to claim 1 , wherein the carbon-based substrate in the step 2 is commercial carbon paper, carbon cloth and carbon felt, or a substrate with a plane, which is made of a carbon material by a pressing or film extracting method.

7. The preparation method according to claim 1 , wherein the reducing/protecting gas in the step 3 and the step 4 is mixed gas of hydrogen and argon or hydrogen and nitrogen, a proportion of the hydrogen is 10% to 50%, and a total gas flow is 100 sccm to 800 sccm.

8. The preparation method according to claim 1 , wherein the preset pressure in the step 3 is 1 atmospheric pressure.

Assignees

• Univ Nankai
• Nankai Cangzhou Bohai New Area Green Chemical Res Co Ltd

Inventors

• Chen Jun
• Hao Zhimeng
• Yan Zhenhua
• Li Haixia

Classifications

• C22F1/02

  in inert or controlled atmosphere or vacuum (adjusting the composition of the atmosphere C21D1/76) · CPC title

• C22F1/08

  of copper or alloys based thereon · CPC title

• C30B29/64

  Flat crystals, e.g. plates, strips or discs · CPC title

• C30B1/02 Primary

  by thermal treatment, e.g. strain annealing (C30B1/12 takes precedence) · CPC title

• C30B1/12

  by pressure treatment during the growth · CPC title