Plasma etching method for etching organic matter layer

Abstract

The invention relates to a plasma etching method for etching an organic matter layer, aiming to solve the problem that when an organic matter layer is etched, the central area and the marginal area of a substrate has non-uniform etching effects. In the etching method, a gas distributing device is utilized to supply etching gas for the central area of the substrate, and supply side wall protectivegas for the marginal area of the substrate, wherein the etching gas and the side wall protective gas are mutually isolated before entering a reaction area above the substrate in a reaction cavity. When introduced into the reaction cavity from the gas distributing device, the etching gas and the side wall protective gas are gradually dispersed and mixed, and finally, reaction gas containing the etching gas and the side wall protective gas in different mixing proportions is obtained on the surface of the substrate. The different mixing proportions ensure that the central area and the marginal area of the substrate can counteract etching effect difference caused by other factors, and finally, the central area and the marginal area have uniform etching effect.

Description

technical field [0001] The invention relates to the field of manufacturing semiconductor devices, in particular to a plasma etching method for an organic layer. Background technique [0002] The etching process refers to the process of removing unnecessary parts in the substrate or in the film layer on the surface of the substrate by using chemical solution or corrosive gas or plasma in the process of manufacturing semiconductor devices. Generally, the etching method mainly using chemical solution is wet etching, and the etching method using corrosive gas or plasma is dry etching. At present, dry etching, which can make circuit patterns finer, is more and more widely used. [0003] In wet etching, the chemical reaction of strong acid is used for isotropic etching, even the part covered by the mask can be etched. In contrast, dry etching uses reactive ion etching, in which etching is performed with a corrosive chemical gas, such as a halogen in a plasma, and plasma ions. T...

AI Technical Summary

Problems solved by technology

However, in the actual etching process, the researchers found that when such a gas composition is mixed and then fed into the reaction chamber for etching, the middle area of ​​the substrate will obtain a better etching effect, while the edge area of ​​the substrate will appear severely bowed. )Happening

Moreover, this situation is difficult to improve, because the oxygen-containing etching gas and the reaction gas that can improve the bow shape have been mixed before entering the reaction area, so the gas ratio of the two is relatively relative to the middle area and the middle area of ​​the substrate. The edge area is the same, and it is fixed and cannot be adjusted, so even adjusting the ratio of the mixed gas intake rate between the middle and the edge still cannot effectively improve this situation, and eventually the middle area and edge area of ​​the substrate appear uneven etching appearance

Images