The Study of Boron Pre-dep Process Improved by Low-pressure Chemical Vapor Deposition Technology

• Main Authors: HUANG, JEN-CHIEH, 黃仁杰
• Other Authors: Ho, Jyh-Jier
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/28839318708398702378

碩士 === 國立臺灣海洋大學 === 電機工程學系 === 102 === Current low concentration (440 ohm/sq) boron pre-deposition processes can not achieve good uniformity performance, results in poor reproducibility and cause to additional processes &; production cycle time. This paper investigates a strategy to reduce non-uniformity of sheet resistance of wafers and that can satisfy the requirement of 1500 ohm/sq boron pre-deposition designing new devices. By applying temperature gradient to low pressure chemical Oxidation deposition (LPCVD), the shallow-diffusion process can be removed and the total boron pre-deposition processes reduced from three steps to two steps. This strategy significantly minimizes the variance from temperature unstability, reduces sheet-rho uniformity (within-tube) from 30.89% to 4.28% and standard deviation (Std Dev) from 48.24 to 5.56, decrease production cycle time and double the producting efficency. The modified processes have the capability that can achieve 1500 ohm/sq of sheet-rho with non-uniformity less than 10% and that can achieve 97% yield for new devices with ultra low concentration.