First Insights into Electro-Thermal Stress Driven Time-Dependent Permanent Degradation Failure of CVD Monolayer MoS2 Channel

• Published in: 2020 IEEE International Reliability Physics Symposium (IRPS) pp. 1 - 4
• Main Authors: Ansh, Ansh, Sheoran, Gaurav, Kumar, Jeevesh, Shrivastava, Mayank
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.04.2020
• Subjects: CVD MoS 2; Degradation; Materials reliability; Metals; Photoluminescence; Resistance; Silicon; Sulfur; Transition Metal Dichalcogenides (TMDs)
• ISSN: 1938-1891
• DOI: 10.1109/IRPS45951.2020.9129173

This work reports, for the first time, time dependent degradation and failure of CVD monolayer MoS 2 based field-effect transistor channel under DC voltage stress, which seem to have originated from its unique molecular description. Degradation was found to be permanent, which takes place at fields lower than critical field for breakdown and have been discovered to be a strong function of channel temperature and e-field. Strong dependence of channel current on self-heating across the channel has also been observed, which resulted in significant drop in channel current under stress, which however recovers when stress was removed. Reversal in degradation trends and permanent channel failure was observed at lower (77-150K) channel temperatures. Unique localized low resistance regions as well as field assisted physical damage result in overall (ON and OFF state) performance degradation of MoS 2 transistors. Micro-Raman and Photoluminescence investigations, as a function of stress time, are performed to investigate the micro-origin of permanent degradation and failure.