Active Trap Determination at the Interface of Ge and In_(0.53)Ga_(0.47)As Substrates with Dielectric Layers

摘要

Due to the high carrier mobility, Ge and III-V semiconductors are attractive as active channels for post-Si metal oxide semiconductor (MOS) devices. However, integration of gate dielectrics on high-mobility substrates is frequently jeopardized by the electrical activity of traps nearby the interface. Active traps determination at the interface between the two semiconductors with gate dielectrics has been conducted with the aim to validate several electrical passivation methodologies. In particular, GeO_2 and LaGeO_x passivations of Ge are investigated by conjugating magnetic resonance spectroscopy and electrical response of the MOS capacitors. The case of In_(0.53)Ga_(0.47)As is addressed by tailoring the surface treatments and the growth parameters in the trimethyaluminum based atomic layer desposition of Al_2O_3 films. The electrical quality of the Al_2O_3/In_(0.53)Ga_(0.47)As interface is assessed by exploring the temperature dependent electrical response of the MOS capacitors and admittance spectroscopy of the active traps energetically distributed in the In_(0.53)Ga_(0.47)As bandgap.