Wafer processing method

Abstract

The invention provides a wafer processing method, being able to inhibit the concavo-convex influence on the front side while grinding the back side of a wafer, and being simple in processing after grinding. The wafer processing method includes an annular groove forming step, a close contact making step, a step of forming a wafer with a protective member, a grinding step, and a peeling step. The wafer has a device area and a peripheral marginal area surrounding the device area on the front side, and devices each having asperities are formed in the device area. In the annular groove forming step, an annular groove is formed on the front side of the wafer along the inner circumference of the peripheral marginal area, and the depth of the annular groove exceeds the finishing thickness of the wafer. I n the close contact making step, the device area and the annular groove are covered with a protective film, and the protective film is bring into close contact with the front side of the wafer. In the step of forming a wafer with a protective member, a wafer with a protective member is formed by covering the protective film and the exposed peripheral marginal area are covered with the protective member formed by hardened liquid resin. In the grinding step, the back side of the wafer is grinded to thin the wafer to the finishing thickness while the protective member side is retained. Inthe peeling step, the protective member and the protective film are peeled off from the device area.

Description

technical field [0001] The present invention relates to a wafer processing method which is used when grinding a wafer having concavities and convexities on the front surface. Background technique [0002] In order to reduce the size and weight of device chips incorporated into various electronic devices, etc., chances of thinning wafers before being divided into device chips increase. For example, the wafer can be ground and thinned by holding the front side of the wafer on which the device is installed by a chuck table and pressing a rotating grinder tool to the back side of the wafer. [0003] When grinding a wafer by the above-mentioned method, a protective member is usually attached to the front side of the wafer (for example, refer to Patent Document 1). Thereby, it is possible to prevent the device on the front side from being damaged due to force applied during grinding or the like. As the protective member, for example, an adhesive tape formed of a material such as...

AI Technical Summary

Problems solved by technology

However, since the substrate is bonded to the wafer with an adhesive such as thermoplastic wax, cumbersome operations such as dipping the substrate in a solution or heating at a high temperature are required when peeling the substrate from the ground wafer.

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