Silicon wafer etching method, method for preparing antireflective texture surface on silicon wafer surface and method for etching specific patterns on silicon wafer surface

Abstract

The invention provides a silicon wafer etching method, a method for preparing an antireflective texture surface on the silicon wafer surface and a method for etching specific patterns on the silicon wafer surface, and belongs to the technical field of semiconductor etching. A solid MnO2 is used as oxidant, HF and other non-oxidizing acid are used for providing an acidic environment for enhancing the oxidizability of the solid MnO2. The solid MnO2 shows oxidation in the acidic environment and contacts the silicon wafer to oxidize the silicon, the generated SiO2 is etched by the HF acid, and the exposed new silicon surface contacts the solid MnO2 for further oxidation. As the reaction proceeds, the etched structure is formed at the position where the silicon wafer contacts the solid MnO2, and the solid MnO2 is finally reduced to the soluble Mn2+ ions. The method can be used for fixed etching at the place of the silicon wafer surface requiring etching and can also be used for preparation of the antireflective texture surface on the surface of polysilicon wafer, and the texture surface with low reflectivity can be obtained without using precious metal or nitric acid.

Description

technical field

[0001] The invention relates to the technical field of semiconductor etching, in particular to a method for etching a silicon chip, a method for preparing an anti-reflection texture on the surface of a silicon chip and a method for etching a specific pattern on the surface of a silicon chip. Background technique

[0002] Etching silicon wafers to form patterned or randomly distributed micro-nano structures is a necessary step in the manufacture of many semiconductor devices. The techniques for etching silicon wafers are mainly divided into dry etching and wet etching.

[0003] Dry etching mainly utilizes reactive gas or / and plasma to etch through chemical or / and physical action. A representative method for dry etching of silicon wafers is reactive ion etching (RIE: Reactive Ion Etching), which is usually a combination of reactive gases containing halogen atoms (such as CF 4 / O 2 , SF 6 / O 2 etc.) into the plasma electric field, combined with the chemical...

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