Author(s): Zhang, D (Zhang, Di); Yuan, GD (Yuan, Guodong); Zhao, S (Zhao, Shuai); Lu, J (Lu, Jun); Luo, JW (Luo, Junwei)

Source: JOURNAL OF PHYSICS D-APPLIED PHYSICS Volume: 55 Issue: 35 Article Number: 355110 DOI: 10.1088/1361-6463/ac7366 Published: SEP 1 2022

Abstract: Thermal budget is a vital element of Si-based superlattice material processing. In this work, a novel n-type ohmic contact scheme with a low thermal budget process is developed by combining high-dose ion implantation and low-temperature alloying techniques. The optimized specific contact resistivity (rho (c)) is reduced to 6.18 x 10(-3) omega cm(2) at a low thermal budget of 400 degrees C, and this is a result of the efficient low-temperature electrical activation of amorphous substances. It is indicated that both the high doping concentration and the formation of a NiSi(Ge) alloy phase contribute to the linear ohmic contact behavior. The ohmic contact resistance dependence on processing temperature is further revealed by a detailed Ni/Si(Ge)alloying model. A minimum rho (c) of 2.51 x 10(-4) omega cm(2) is achieved at a thermal budget of 450 degrees C, which is related to the high bonding intensity at the metal-semiconductor interface. Note that this technique is compatible with standard Si-based CMOS process flows and can be applied in high-performance insulated-gate field-effect transistor (IGFET) fabrication. Furthermore, it is verified that the Si/Ge superlattice structures in our IGFETs can serve as an efficient potential barrier to constrain electrons.

Accession Number: WOS:000813916200001

ISSN: 0022-3727

eISSN: 1361-6463

Full Text: https://iopscience.iop.org/article/10.1088/1361-6463/ac7366