High performance sub-20-nm-channel-length extremely-thin body InAs-on-insulator tri-gate MOSFETs with high short channel effect immunity and Vth tunability

摘要

We have investigated the effects of vertical scaling and the tri-gate structure on electrical properties of extremely-thin-body (ETB) InAs-on-insulator (-OI) MOSFETs. It was found that body thickness (T_body) scaling provides better SCEs control, whereas T_body scaling causes the reduction of the mobility limited by channel thickness fluctuation (δT_body) scattering (μ_fluctuation). To achieve better SCEs control, the thickness of channel layer (T_channel) scaling is more favorable than the thickness of MOS interface buffer layer (T_buffer) scaling, indicating necessity of quantum well (QW) channel structure. Also, the Tri-gate ETB InAs-OI MOSFETs shows significant improvement of short channel effects (SCEs) control with small effective mobility (μ_eff) reduction. As a result, we have successfully fabricated sub-20-nm-L_ch InAs-OI MOSFETs with good electrostatic with S.S. of 84 mV/dec, DIBL of 22 mV/V, and high transconductance (G_m) of 1.64 mS/um. Furthermore, we have demonstrated wide-range threshold voltage (V_th) tunability in Tri-gate InAs-OI MOSFETs through back bias voltage (V_B) control.