InGaP wet etching method

Abstract

The invention relates to the technical field of semiconductor manufacturing, and particularly relates to an InGaP wet etching method. The method comprises the following steps: an InGaP layer grows on a substrate or an epitaxial layer; a wet etching method is adopted to etch the substrate or the epitaxial layer, and an SiN layer grows on the InGaP layer; a reactive ion beam etching method is adopted to etch the SiN layer; dilute hydrochloric acid is adopted to clean the surface of a wafer, and a surface oxide thin layer is removed; weak ammonia is adopted to clean the surface of the wafer, residual H<+> ions after the dilute hydrochloric acid processes the surface of the wafer are removed, and OH- is dangled on a dangling bond; a mixed acid solution of concentrated hydrochloric acid and phosphoric acid is adopted to etch the InGaP layer; and the weak ammonia is adopted to clean the surface of the wafer, residual H<+> ions after the wafer surface is processed by InGaP, and OH- is dangled on a dangling bond. Influences on the surface of the InGaP layer by a preceding process can be removed, and smooth going of the HBT process is ensured.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to an InGaP wet etching method. Background technique [0002] GaAs is the most important and widely used semiconductor material among III-V compound semiconductors. The electron mobility in GaAs is 6 times that of silicon (Si), and its electron peak drift velocity is 2 times that of Si. Therefore, GaAs devices have the characteristics of high frequency, high speed, low power consumption, low noise, and monolithic integration. [0003] GaAs HBT devices are widely used in smartphones and base stations, which have the following advantages (source doctoral thesis: Research on InGaP / GaAs microwave HBT devices and VCO circuits): [0004] 1. Single positive power supply operation. Unlike depletion-type FET and HEMT devices, a negative voltage must be applied to pinch off the channel. The turn-on voltages of HBT are all positive, and only one positive power supply is...

AI Technical Summary

Problems solved by technology

[0015] The embodiment of the present invention provides an InGaP wet etching method, which solves the problem that the HBT process cannot be guaranteed to proceed smoothly due to the influence of the previous process on the surface of the InGaP layer when etching the InGaP layer in the prior art.

Images