Title:
WELDING PROCESS FOR CLADDING COPPER ON BACK SURFACE OF WAFER
Document Type and Number:
WIPO Patent Application WO/2021/056778
Kind Code:
A1
Abstract:
Disclosed is a welding process for cladding copper on the back surface of a wafer, belonging to the technical field of wafer manufacturing. The process comprises the following steps: S1, grinding; S2, cleaning; S3, annealing; S4, grinding and cleaning for the second time, involving: repeating steps S1 and S2 on an annealed copper sheet (2); S5, printing, involving: printing a solder paste on the upper surface of the copper sheet (2); S6, welding, involving: placing a wafer (5) on the copper sheet (2) on which the solder paste printing is completed, wherein the back surface of the wafer (5) is in contact with the copper sheet (2), an upper substrate (1) is placed above the wafer (5) and a lower substrate (3) is placed below the copper sheet (2) to form a welding mechanism, the welding mechanism is placed in a vacuum welding furnace for welding at a welding temperature of 290ºC, and cooling is carried out after welding; S7, cleaning, involving: soaking the wafer (5), on which the copper sheet (2) is welded, by using bromopropane, then carrying out ultrasonic cleaning, and then soaking same by using alcohol and carrying out ultrasonic cleaning; and S8, carrying out hole detection. The present invention is used for solving the technical problems in the prior art of the temperature of a chip rising, and the chip being prone to breakage during packaging.
Inventors:
ZHANG RU (CN)
ZANG TIANCHENG (CN)
JIANG WEIBIN (CN)
AN YONG (CN)
JIN HAO (CN)
ZANG TIANCHENG (CN)
JIANG WEIBIN (CN)
AN YONG (CN)
JIN HAO (CN)
Application Number:
PCT/CN2019/119752
Publication Date:
April 01, 2021
Filing Date:
November 20, 2019
Export Citation:
Assignee:
YANTAI TAIXIN ELECTRONIC TECH CO LTD (CN)
International Classes:
H01L21/60
Foreign References:
| CN208240652U | 2018-12-14 | |||
| CN107498128A | 2017-12-22 | |||
| CN103785991A | 2014-05-14 | |||
| US20050040513A1 | 2005-02-24 |
Attorney, Agent or Firm:
BEIJING ZHONGCHUANG BOTEN INTELLECTUAL PROPERTY AGENCY (GENERAL PARTNERSHIP) (CN)
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