Quantum transport characteristics in single and multiple N-channel junctionless nanowire transistors

• 作 者: 王昊 韩伟华 马刘红 李小明 杨富华
• 机 构: Engineering Research Center for Semiconductor Integration Technology, Institute of Semiconductors,Ch
• 出 处: Chinese Physics B
• 发表日期: 2014年08期
• 关键词: drain confinement spacing versus possibly steps Coulomb superposition impurity f

Single and multiple n-channel junctionless nanowire transistors(JNTs) are fabricated and experimentally investigated at variable temperatures. Clear current oscillations caused by the quantum-confinement effect are observed in the curve of drain current versus gate voltage acquired at low temperatures(10 K–100 K) and variable drain bias voltages(10 mV–90 mV). Transfer characteristics exhibit current oscillation peaks below flat-band voltage(VFB) at temperatures up to 75 K,which is possibly due to Coulomb-blocking from quantum dots, which are randomly formed by ionized dopants in the just opened n-type one-dimensional(1D) channel of silicon nanowires. However, at higher voltages than VFB, regular current steps are observed in single-channel JNTs, which corresponds to the fully populated subbands in the 1D channel. The subband energy spacing extracted from transconductance peaks accords well with theoretical predication. However, in multiple-channel JNT, only tiny oscillation peaks of the drain current are observed due to the combination of the drain current from multiple channels with quantum-confinement effects.

Clear current oscillations caused by the quantum-confinement effect are observed in the curve of drain current versus gate voltage acquired at low temperatures (10 K- 100 k) and variable drain bias voltages (10 mV-90 mV). Transfer characteristics exhibit current oscillation peaks below flat-band voltage (VFB) at temperatures up to 75 K, which is possibly due to Coulomb-blocking from quantum dots, which are randomly formed by ionized dopants in the just opened n-type one-dimensional (1D) channel of silicon nanowires. However, at higher voltages than VFB, regular current steps are observed in single-channel JNTs, which corresponds to the fully populated subbands in the 1D channel. The subband energy spacing extracted from transconductance peaks accords well with theoretical predication. However, in multiple-channel JNT, only tiny oscillation peaks o f the drain current are observed due to the combination of the drain current from multiple channels with quantum-confinement effects.