Windowing-based double-sided thick copper film electroplating process

Abstract

The invention discloses a windowing-based double-sided thick copper film electroplating process and belongs to the field of wafer processing. The process comprises the following steps of: S1, sequentially plating an adhesion layer, a barrier layer and a copper seed layer on the back surface of a wafer; S2, bonding a glass carrier plate; S3, grinding and etching the back surface of the wafer; S4, performing a manufacturing process; S5, plating Ti / Ni / Cu is; S6, performing windowing; S7, performing a lithography imaging process on the front surface of the wafer; S8, performing a lithography imaging process on the back surface of the wafer; S9, removing a photoresist layer after double-sided thick film electroplating; S10, removing the Ti / Ni / Cu on the two sides by etching; S11, etching a silicon cutting channel by using SF6 plasma until exposing the adhesive layer; S12, carrying out thin film deposition operation; S13, etching silicon oxide or silicon nitride to form a side wall; S14, carrying out cleaning and etching; S15, enabling the wafer to be attached to a blue film frame; S16, removing the glass carrier plate from the wafer; and S17, cleaning the adhesive layer on the wafer. Therefore, the wafer is bonded with the glass carrier plate to form an ultrathin wafer, and a glass carrier plate window is formed at the contact point of the front surface of the wafer, so that the problem of electric leakage between thick film copper and a packaging material is solved.

Description

technical field [0001] The invention relates to the field of wafer processing, and more specifically relates to a double-sided electroplating thick copper film process with window openings. Background technique [0002] In the design and structure of high-power, high-voltage / current semiconductor components, it is very important to use thick-film copper heat sink (Cuheat Sink), otherwise the components will cause serious reliability problems due to local damage caused by overheating, and super Thin wafers are extremely important for low-resistance and high-frequency operation. How to combine ultra-thin wafers with double-sided electroplated thick-film copper heat dissipation wires and the structure and installation method of the protection of the side walls of the cutting surface are the core of the present invention. . Existing technology. Shortcomings of the prior art: 1. If the thick-film copper plating on the back of the ultra-thin wafer is done, due to the stress and t...

AI Technical Summary

Problems solved by technology

Existing technology. Shortcomings of the prior art: 1. If the thick-film copper plating on the back of the ultra-thin wafer is done, due to the stress and the difference between the coefficient of thermal expansion Cu and Si are large, there will be problems of layering and warping Crack; 2. Electroplating thick Cu film on the front and back at the same time cannot be implemented without the technology of opening windows on the glass substrate. If the front side is implemented first, the wafer stress problem will make it impossible to electroplate the thick Cu film on the back; It is very difficult to use traditional cutting and plasma cutting processes on the circle; 4. It is also very difficult to debond the double-sided thick film Cu on the glass carrier after cutting, and it is also very difficult when cutting ultra-thin wafers or transferring them to Dicing Frame The possibility of fragmentation is very high; 5. The current cutting technology cannot implement sidewall protection for the separated crystal grains, and it is difficult to avoid the reliability problem of current leakage (leakage Problem) in high-power operation of packaging materials and thick-film wires

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