Method for etching chip

Abstract

The invention provides a chip etching method. The chip consists of a protective layer, a metal layer, an oxide layer and a bottom layer. The method includes a breakthrough step, a main etching step and an over etching step; wherein, the breakthrough step completes the etching of the protective layer; the main etching step completes the etching of the metal layer; the over etching step completes the etching of the oxide layer; the main etching step can be divided into a first main etching step and a second main etching step; the first main etching step controls the completion of etching by controlling the time of etching; the second main etching step controls the completion of etching via a signal returned from the end point of the metal layer. As different etching controlling methods are used in the two steps of the main etching step in the etching method, the consistence of the chip surface can be enhanced, and the pipe trenches generated in the oxide layer in the past can be eliminated so as to improve the yield of the chip.

Description

technical field [0001] The invention belongs to the field of chip design and relates to a chip etching method. Background technique [0002] With the rapid development of modern social life, various electronic products have been integrated into the life of modern society one after another, bringing a lot of convenience to users. These electronic products are equipped with different chips, and the chip is to gather circuit elements such as transistors, diodes, resistors and capacitors on the chip to form a complete logic circuit to achieve functions such as control, calculation or memory, so that electronic products can be used. Its functions and handle various affairs of users are quite convenient. [0003] A chip generally includes a protective layer, a metal layer, an oxide layer, and a bottom layer, among which the protective layer, the metal layer, and a part of the oxide layer need to be etched; the breakthrough step, the main etching step, and the overetching step are...

AI Technical Summary

Problems solved by technology

In the above two steps, BCl 3 The flow rate and the energy of the lower electrode are too high, and the BCl 3 The higher the flow rate and the higher the energy of the lower electrode, the stronger the bombardment on the chip, and it is easy to cause the chip to cause trench defects

At the same time, the etching pressure of the above two steps is slightly lower, the lower the pressure, the worse the uniformity of the entire chip etching

Images