Method for deposition compact SiO2 with low damnification PECVD

Abstract

The invention discloses a low damage PECVD depositing compact SiO2 mask layer method, comprising the following steps: step 1: rinsing GaN substrate: the GaN substrate is rinsed with cleaning liquid and is dried; step 2: depositing SiO2 mask layer: the rinsed and dried GaN substrate is put in the PECVD vacuum chamber to deposit SiO2; step 3: after depositing SiO2, N2 is constantly added, and when the temperature of the chamber reduces the GaN substrate draws from the vacuum chamber to the pre-chamber, and the GaN substrate deposited with SiO2 mask layer is taken out; step 4: using an ellipsometer to measure the thickness of the growing SiO2 mask layer.

Description

Technical field The invention is used in the technical field of optoelectronic device manufacturing, and specifically relates to a low-damage PECVD deposition of dense SiO in the preparation process of gallium nitride (GaN)-based power light-emitting diodes (LEDs). 2 Methods. Background technique In the process of preparing GaN-based LEDs, inductively coupled plasma (ICP) dry etching technology is usually used to form the mesa and electrodes. Generally, the etching is relatively deep. Therefore, the GaN-based material has a high risk of etching the masking layer material. The selection ratio is very important. Currently, there are three main types of masks commonly used for ICP dry etching: photoresist, SiO 2 / SiN X and metallic materials such as Ni. The production process of photoresist is simple, but the photoresist uses plasma C 12 and B.C. 13 The selectivity ratio of etching gas to AZ9260 photoresist is lower than 0.6:1, and after ICP etching, the remaining photore...

AI Technical Summary

Problems solved by technology

Currently used PECVD deposited SiO 2 method, generally in order to increase the deposition of SiO 2 Density and insulation strength, reduce the damage to the material during the ICP etching process, usually deposited under the radio frequency power greater than 80W, causing the radio frequency power to damage the material itself during the deposition process, resulting in increased leakage current and reduced luminous intensity of the device , affecting the reliability of power LEDs, however, too low PECVD deposition power will lead to SiO 2 Reduced density and insulation of the masking layer

Therefore, existing deposition methods cannot reduce the low damage of PECVD deposition process while having SiO 2 High compactness and dielectric strength

Images