Carrier Accumulation in Silicon-On-Insulator Structures Containing Ge Nanocrystals in the Burried SiO2 Layer
Electro-physical properties of metal-oxide-silicon (MOS) structures and MOS transistors, prepared in the top silicon layer of silicon-on-insulator (SOI) structures containing Ge nanocrystals in the buried SiO2 layers, have been studied. It was obtained that carrier accumulation in MOS structures depend on the direction of built-in electrical field in MOS structures. Accumulation of the excess negative charges in the case of p-channel transistors is associated with electron trapping on Ge nanocrystals synthesized in the buried dielectric. In the case of n-channel transistor, positive charge related to the Si/SiO2 interface or to the charged oxide is accumulated. The Ge atoms diffused to the SiO2/Si interface can stimulate the formation of the excess positive charge.
B. Pichaud, A. Claverie, D. Alquier, H. Richter and M. Kittler
I. E. Tyschenko et al., "Carrier Accumulation in Silicon-On-Insulator Structures Containing Ge Nanocrystals in the Burried SiO2 Layer", Solid State Phenomena, Vols. 108-109, pp. 77-82, 2005