Study of all nitride gate stack with Metal and Insulator HfNx for high mobility channel

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560390
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: MAEDA Tatsuro 独立行政法人産業技術総合研究所, ナノエレクトロニクス研究部門, 主任研究員 (40357984)
• Co-Investigator(Kenkyū-buntansha): YASUDA Tetsuji 独立行政法人産業技術総合研究所, ナノエレクトロニクス研究部門, 研究部門長 (90220152)
• Co-Investigator(Renkei-kenkyūsha): TANAKA Masatoshi 国立大学法人横浜国立大学, 工学研究院, 教授 (90130400)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 高移動度チャネル / ゲルマニウム / ゲートスタック / 窒化物

Outline of Final Research Achievements

In this study, we investigate the material potential of HfNx films as a gate material as well as a metal gate for germanium metal-insulator-semiconductor (Ge-MIS) structure. We demonstrate the capabilities of reactive DC magnetron sputtering to control the electrical behavior of HfNx films from metal (~349uΩcm) to insulator only by changing nitrogen flow rate. To investigate the electrical properties of all nitride Ge gate stacks, we fabricate Ge MIS structures straightforwardly by sequential deposition of insulator-HfNx and metal-HfNx on Ge substrate. It is found that insulating HfNx film shows a high-k value of 15~20 with the bandgap of 2.9 eV and the insulator-HfNx/Ge interface shows an excellent interface quality with low interface trap of 4E12cm-2eV-1. We therefore address that insulating and metallic HfNx films have a high potential as gate insulator and metal in non-oxide Ge MIS structures.

Free Research Field

半導体