Silicon electrode corrosion method

Abstract

The invention discloses a silicone electrode corrosion method. The method comprises the following steps that (1) a silicone electrode is immersed and cleaned in an HF acid solution, and residual acidsolution and impurities in gas ports are cleaned in an ultrasonic way; (2) the silicon electrode is placed in a baking oven so that residual moisture in the gas ports is evaporated by hot air, and thesilicon is cooled into the room temperature and then mounted in a corrosion tool; (3) the corrosion tool is placed in a corrosion fluid to corrode the silicon electrode, the concentration and temperature of the corrosion fluid are adjusted to determine the corrosion rate, and rotating speed and corrosion time of the corrosion tool are adjusted to reach a set corrosion removal amount; and (4) thecorroded silicon electrode is placed and immersed in deionized water and rotated, spraying cleaning is carried out, and residual acid solution in the surface and gas ports of the silicon electrodes are removed in the ultrasonic way. The method of the invention can improve the surface flatness and morphology of the silicon electrode as well as the diameter uniformity of the gas ports in different position greatly.

Description

technical field [0001] The invention relates to a method for etching silicon electrodes. Background technique [0002] Generally, when manufacturing semiconductor integrated circuits, it is necessary to make an interlayer insulating layer (SiO2) formed on a silicon wafer. 2 ) for the etching process. In order to etch a silicon wafer with an insulating layer, a plasma etching device is used. In this plasma etching device, the etching gas is directed toward the silicon wafer through the through pores provided in the silicon electrode plate, and a high-frequency voltage is applied at the same time, thereby generating plasma between the silicon electrode plate for plasma etching and the silicon wafer. , the plasma acts on the silicon wafer to etch the insulating layer on the surface of the silicon wafer. In this process, the silicon wafer is placed on a stage directly below the silicon electrodes. Due to the difference in device structure or silicon wafer size, the structure...

AI Technical Summary

Problems solved by technology

[0004] The geometric shape of the silicon electrode and the air guide hole are generally completed by a machining center and a drilling center. In the existing etching process, a simple fixed tool is generally used to move the silicon electrode vertically up and down in the etching solution tank for etching. The pressure change and the difference in the temperature of the etching solution will lead to inconsistency in the amount of corrosion removal at different positions of the silicon electrode, and inconsistency in the diameter of the air hole after corrosion; the data in actual operation shows that the bottom of the silicon electrode, that is, the lower part of the etching solution, due to the high pressure, The temperature of the corrosive liquid is high, the amount of corrosion removal is large, and the diameter of the air guide hole is large, while the upper part has a small amount of corrosion removal and a small diameter of the air guide hole. There will be an obvious gradual trend in the measurement, that is, from one side of the silicon electrode to the other. On one side, the diameter of the air guide hole gradually increases or decreases, and the flatness gradually increases or decreases, resulting in the deterioration of the uniformity of the overall geometric parameters of the silicon electrode, which cannot be effectively improved through subsequent grinding, polishing and other processes

In the integrated circuit etching process, the etching effect of the fixed area will be poor, unstable, and the yield rate will be low