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Selenium Segregation for Lowering the Contact Resistance in Ultrathin-Body MOSFETs With Fully Metallized Source/Drain

Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore, Singapore
IEEE Electron Device Letters (Impact Factor: 2.79). 11/2009; DOI: 10.1109/LED.2009.2028660
Source: IEEE Xplore

ABSTRACT We report the first integration of selenium (Se) segregation contact technology in ultrathin-body (UTB) n-MOSFET featuring Ni fully silicided source and drain. During the Ni silicidation process, the implanted Se segregated at the NiSi-n-Si interface, leading to significant reduction of Schottky barrier height and contact resistance. The UTB n-MOSFETs integrated with Se segregation (SeS) contact technology show significant external series resistance reduction and drive current performance enhancement. Drain-induced barrier lowering and gate leakage current density are not adversely affected by the SeS process.

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