Effects of P addition on the Interfacial Structures and Electrical Properties of Ni Silicides

• Main Authors: Chia-Liang Wu, 吳家樑
• Other Authors: Hsun-Feng Hsu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/79944912876452267164

碩士 === 國立中興大學 === 材料科學與工程學系所 === 99 === As the dimensions of devices are reduced to the nanometer scale, flat shallow metal/Si electrical contacts must be formed in the source/drain regions of metal-oxide-semiconductor field-effect transistor (MOSFET) devices. This work demonstrates a method for the formation of epitaxial NiSi2 layers with atomically flat silicide/silicon interface by a solid-phase reaction in Ni-P (9 nm)/Si(100) samples. The mechanism of the formation of this atomically flat interface has also been investigated by observing the change of interfacial morphology in Ni-P/Si(100) samples annealing at 700°C for various durations. The results indicate that in Ni-P(9 nm)/Si(100) system, the faced silicide/silicon interface transferred to flat with the increase of the annealing duration, which is caused by a reduction in the total interface area. When the atomically flat interface formed (annealing for 10-20 s), the sheet resistance of NiSi2 layer was low due to reducing the interface scattering of conduction electron. When the Ni3P particle was precipitated (annealing for over 30 s), the sheet resistance was increased due to increasing the impurity scattering of conduction electron. Additionally, the Schottky barrier height (SBH) was reduced with the increasing of the annealing duration, because the amount of {111} interface decreased. As the atomically flat (100) interface was formed, an Ohmic junction was obtained because the precipitation of P at the silicide/silicon interface affected the electrically contact properies.