以電子迴旋共振化學氣相沈積技術成長矽氧膜和矽氧氮膜之研究

Abstract

本論文包括兩部份：第一部份是電子迴旋共振氣相沈沈積之矽氧膜之研 究，第二部分則為矽氧氮膜之研究.在第一部份中，我們試著從壓力，能 量，溫度，流量比及用不同氣體在沈積前事先處理晶片這些變數來觀察其 對膜之品質之影響.我們發現在低壓，較高的溫度，某一範圍之流量比的 條件下，可沈積出組成均勻且與熱 氧化成長的氧化矽膜品質差不多的矽 氧膜.在第二部份中，我們研究了壓力，能量，四氫化矽的量及氮和氧的 流量比對於沈積膜之品質之影響.我們同樣也發現了，在某一特定範圍的 氮和氧的流量比和低壓下，可成長出具有良好阻隔水汽及雜質入侵的矽氧 氮膜介質層. This thesis consists of two portions: ECR CVD oxide and ECR CVD oxynitride. In the study of ECR CVD oxide, we try to find the influences of temperature,pressure, pretreatment or nonpretreatment, power, and SiH4/O2 gas flow rate ratio on the qualities of oxide films deposited by ECR CVD techniques.The temperature is from room temperature to 300 C, pressure is from 0.5 mtorr to 6 mtorr,pretreatment uses N2 and H2 gas, power is from 200 to 350 W, and the gas flow rate ratio is from 3/9 to 0.5/11.5. From our experimental results, we find that at lower pressure(1 mtorr), optimized gas flow rate ratio (1/3 to 1/10),and higher temperature(300 C is enough) we can deposit a stoichiometric and nearthermal oxide film. The second portion of this thesis is on the study oxynitride films deposited by ECR CVD techniques. In our experiments we investigate the influence of pressure,power, SiH4 gas flow rate, and N2/O2 gas flow rate ratio on the film properties.The pressure is from 0.1 mtorr to 3 mtorr , power is from 200 to 400 W, SiH4 gas flow rate is from 0.5 to 2 sccm (at the condition of fixed total N2+ O2 gas flow rate), and N2/O2 gas flow rate ratio is from 3/1 to 39/1. We find that at lower pressure (< 1mtor),and optimized N2/ O2 gas flow rate ratio we can prepare more stochiometric and good moisture and imputities blocking film. The N2/O2 gas flow rate ratio is very important as we deposited a good dielectric film by ECR CVD.