The characteristics of Si rich silicon nitride/silicon crystal film in SONOS NVM device application

• Main Authors: Hsu wen-ming, 許文銘
• Other Authors: Hwang huey liang
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/13670058102580508770

碩士 === 國立清華大學 === 電子工程研究所 === 93 === In this thesis, we studied the characteristics of Si rich silicon nitride/silicon crystal film in MONOS NVM application. We produced Si rich silicon nitride/silicon crystal film by PECVD and the precursor gas are the mixture of silane diluted to a concentration of 5% in argon and nitrogen gas at purity in excess of 99.9999% under room temperature or 300C ambience. We kept the SiH4 precursor gas flow at 40 sccm and changed the N2 precursor gas flow rates for varying the Si content in SiNx thin film. In electrical characteristics measurement, we measured the initial threshold voltage, program/erase performance, endurance (program/erase cycle), and data retention. Because of the thick ONO stack film (min. ~800 Å), we used the uniform FN tunneling mechanism for program/erase. We found some characteristics are as follows. 1.The initial Vt is increased with raising N2 precursor gas flow rates. This is due to EOT (equipment gate oxide thickness) increased in less Si content of SiNx thin film. 2.The program/erase window (�幀T) is increased with reducing N2 precursor gas flow rates. 3.The endurance performance is less sensitivity with N2 precursor gas flow rates. This is due to uniform FN program/erase mechanism. 4.The data retention performance is improved with raising N2 precursor gas flow rates.