Nanorod field-effect transistors (FETs) that use multiple Mg-doped ZnO nanorods and a SiO2 gate insulator were fabricated and characterized. The use of multiple nanorods provides higher on-currents without significant degradation in threshold voltage shift and subthreshold slopes. It has been observed that the on-currents of the multiple ZnO nanorod FETs increase approximately linearly with the number of nanorods, with on-currents of similar to 1 mu A per nanorod and little change in off-current (similar to 4 x 10(-12)). The subthreshold slopes and on-off ratios typically improve as the number of nanorods within the device channel is increased, reflecting good uniformity of properties from nanorod to nanorod. It is expected that Mg dopants contribute to high n-type semiconductor characteristics during ZnO nanorod growth. For comparison, nonintentionally doped ZnO nanorod FETs are fabricated, and show low conductivity to compare with Mg-doped ZnO nanorods. In addition, temperature-dependent current-voltage characteristics of single ZnO nanorod FETs indicate that the activation energy of the drain current is very low (0.05-0.16 eV) at gate voltages both above and below threshold.
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机译:制作并表征了使用多个掺Mg的ZnO纳米棒和SiO2栅极绝缘体的纳米棒场效应晶体管(FET)。使用多个纳米棒可提供更高的导通电流,而不会显着降低阈值电压漂移和亚阈值斜率。已经观察到多个ZnO纳米棒FET的导通电流随纳米棒的数量近似线性增加,每个纳米棒的导通电流接近1μA,截止电流变化很小(类似于4 x 10( -12))。随着器件通道内纳米棒数量的增加,亚阈值的斜率和通断比通常会提高,这反映出纳米棒到纳米棒的特性具有良好的均匀性。预期在ZnO纳米棒的生长过程中,Mg掺杂剂有助于高n型半导体特性。为了进行比较,制造了无意掺杂的ZnO纳米棒FET,并且与掺Mg的ZnO纳米棒相比显示出低电导率。此外,单个ZnO纳米棒FET随温度变化的电流-电压特性表明,在栅极电压高于和低于阈值时,漏极电流的激活能量非常低(0.05-0.16 eV)。
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