High κ/InGaAs for Ultimate CMOS - Interfacial Passivation, Low Ohmic Contacts, and Device Performance

摘要

In-situ atomic layer deposited (ALD)-HfO_2 has been used to passivate In_(0.53)Ga_(0.47)As. Atom-to-atom interactions for the interfacial electronic/chemical characteristics of in-situ ALD-HfO_2 on pristine molecular beam epitaxy (MBE) grown In_(0.53)Ga_(0.47)As surface have been studied using synchrotron-radiation photoemission (SRPES). ALD-HfO_2/ In_(0.53)Ga_(0.47)As metal-oxide-semiconductor capacitors (MOSCAPs) have exhibited excellent capacitance-voltage (C-V) characteristics. The interfacial trap density spectra in absence of mid-gap peaks were attained. Moreover, 1μm-gate-length self-aligned inversion-channel In_(0.53)Ga_(0.47)As MOS field-effect-transistors (MOSFETs) using in-situ ALD-HfO_2 as the gate dielectric have achieved record-high maximum drain current (I_D) of 1.5 mA/μm and peak transconductance (G_m) of 0.84 mS/μm. Moreover, low contact resistivity (ρ_c) of 6.7×10~(-9) Ω-cm~2 by inserting a 0.6 nm ZnO dielectric layer between titanium metal and InGaAs (with Si doping concentration of 1.5×10~(19) cm~(-3)) has been demonstrated; this contact structure was employed in the source/drain on the implant-free In_(0.53)Ga_(0.47)As quantum-well MOSFETs to obtain peak G_m of 1.25 mS/μm and low source/drain resistance of 190 Ω-μm.