Device physics and design of FD-SOI JLFET with step-gate-oxide structure to suppress GIDL effect

【摘要】 A novel n-type junctionless field-effect transistor（JLFET） with a step-gate-oxide（SGO） structure is proposed to suppress the gate-induced drain leakage（GIDL） effect and off-state current I_off.Introducing a 6-nm-thick tunnel-gateoxide and maintaining 3-nm-thick control-gate-oxide,lateral band-to-band tunneling（L-BTBT） width is enlarged and its tunneling probability is reduced at the channel-drain surface,leading the off-state current I_off to decrease finally.Also,the thicker tunnel-gate-oxide can reduce the influence on the total gate capacitance of JLFET,which could alleviate the capacitive load of the transistor in the circuit applications.Sentaurus simulation shows that I_off of the new optimized JLFET reduced significantly with little impaction on its on-state current I_on and threshold voltage V_TH becoming less,thus showing an improved I_on/I_off ratio（5×10⁴） and subthreshold swing（84 mV/dec）,compared with the scenario of the normal JLFET.The influence of the thickness and length of SGO structure on the performance of JLFET are discussed in detail,which could provide useful instruction for the device design.更多还原

【Abstract】 A novel n-type junctionless field-effect transistor（JLFET） with a step-gate-oxide（SGO） structure is proposed to suppress the gate-induced drain leakage（GIDL） effect and off-state current I_off.Introducing a 6-nm-thick tunnel-gateoxide and maintaining 3-nm-thick control-gate-oxide,lateral band-to-band tunneling（L-BTBT） width is enlarged and its tunneling probability is reduced at the channel-drain surface,leading the off-state current I_off to decrease finally.Also,the thicker tunnel-gate-oxide can reduce the influence on the total gate capacitance of JLFET,which could alleviate the capacitive load of the transistor in the circuit applications.Sentaurus simulation shows that I_off of the new optimized JLFET reduced significantly with little impaction on its on-state current I_on and threshold voltage V_TH becoming less,thus showing an improved I_on/I_off ratio（5×10⁴） and subthreshold swing（84 mV/dec）,compared with the scenario of the normal JLFET.The influence of the thickness and length of SGO structure on the performance of JLFET are discussed in detail,which could provide useful instruction for the device design.更多还原