Method for ultrasonic cleaning of polished sapphire substrate wafer

Abstract

The invention relates to a method for ultrasonic cleaning of a polished sapphire substrate wafer and provides a method for conducting cleaning through ultrasound and a solution to remove particles and metal ions and then conducting cleaning through ultrasound and oxidation liquid to remove organic matters. According to removal of the particles and the metal ions, an FA / O type chelating agent and two kinds of non-ionic surface active agents including JFC and AEO are selected and prepared to mixed liquid in proportion and the ultrasonic action is added so that cleaning can be conducted; anodic oxidation liquid obtained through electrolysis of a diamond film (BDD) is selected to remove organic pollution, the oxidation liquid is high in oxidation function, and therefore most organic matters are resolved. According to the method, comprehensive cleaning of the particles, the organic matters and metal impurities is conducted, the number of steps is small, operation is simple, and the method can satisfy the requirement of the new-period micro-electronic cleaning technology.

Description

technical field [0001] The invention belongs to the cleaning technology of wafer surface after CMP, in particular to an ultrasonic cleaning method after polishing of sapphire substrate wafer. [0002] Background technique [0003] As the third-generation semiconductor material after Si and GaAs, GaN has undoubtedly become a milestone in the development process of the LED chip manufacturing industry. At present, vigorously developing GaN-based LED light-emitting materials has become the development trend and focus of the lighting industry in recent years. Since GaN is difficult to prepare bulk materials, thin films must be grown on other substrate materials, so for the manufacture of GaN-based LED chips, the choice of substrate is the primary consideration. There are many kinds of GaN substrate materials, including sapphire, silicon carbide, silicon, magnesium oxide, zinc oxide, etc. Among many materials, sapphire substrate material has become the preferred material for ...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to solve the problem that the existing sapphire cleaning technology has many steps, consumes a lot of chemicals and deionized water, and the use of strong acid, strong alkali and strong oxidant is not only dangerous to operate, but also volatile to cause environmental pollution and physical injury to operators. To provide an ultrasonic cleaning method for sapphire substrate wafers after polishing, which avoids the use of strong acid and strong alkali, reduces environmental pollution, and has high cleaning efficiency