Research On Deposition Of SiO₂ And Si₃N₄ Thin Films By PECVD And The Application In Semiconductor Optoelectronic Device

The research included in this thesis is supported by the National Basic Research Program of China undertaken by Prof. Ren Xiaomin: Basic Research on Compatible Heterogeneous Integration and Functional-Microstructure Assemblage for the Development of Novel Optoelectronic Devices (No.2010CB327600), Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0609) and the second construction projects of 111 project (No. B07005).The silicon nitride thin films and the silicon dioxide thin films are materials with good physical and chemical performance which have been widely applied to semiconductor optoelectronic devices. The silicon nitride thin films and the silicon dioxide thin films are commonly deposited through plasma enhanced chemical vapor deposition (PECVD). PECVD method has the advantages of low deposition temperature, rapid deposition velocity and high compactness etc. In this thesis, the deposition of thin films by using PECVD method is investigated and the influences of deposition parameters are summarized. The application of the silicon nitride thin films and the silicon dioxide thin films in semiconductor photoelectron device is researched. Deposition parameters when using HQ-3 PECVD device to deposit the silicon nitride thin films and the silicon dioxide thin films have been researched. The main work of the dissertation is listed below:1. A series of silicon nitride thin films and silicon dioxide thin films samples are deposited on Si substrate (100) by changing the deposition parameters such as radio frequency (RF) power, deposition temperature, deposition duration and gas flow rate when using HQ-3 PECVD device.2. The silicon nitride thin films samples are tested to obtain the thickness and refractive index. The deposition parameters are optimized according to the test results to obtain silicon nitride thin films with good performance, wherein the thickness of the thin films is about 350 nm and the refractive index of the thin films is about 2.0.3. The silicon dioxide thin films samples are tested to obtain the thickness and refractive index. The deposition parameters are optimized according to the test results to obtain silicon dioxide thin films with good performance wherein the thickness of the thin films is about 250 nm and the refractive index of the thin films is about 1.5.