硅基单电子晶体管的可控制备

Controllable Fabrication of Silicon Based Single-Electron Transistors

采用电子束曝光、感应耦合等离子体刻蚀和热氧化等工艺技术,通过独特的图形反转设计,即在电子束曝光时采用负的曝光图形,并以电子束曝光的光刻胶作为掩膜进行干法刻蚀,通过后续的干法热氧化等工艺,在磷离子重掺杂的绝缘体上硅基底上成功地制备出单电子晶体管。该方法具有高精度、结构可控、可重复和加工成本低的优点,可作为一种批量制备单电子晶体管的工艺技术。所制备的单电子晶体管在2.6 K到100 K的温度范围内呈现出明显的库仑阻塞效应,导通电阻小于100 kΩ。该单电子晶体管将成为高速、高灵敏度射频电路的关键器件。

Single-electron transistors（SETs） were fabricated on phosphorus doped silicon-on-insulator（SOI） substrate with the electron beam lithography,inductively-coupled plasma etching,thermal oxidation and other processes.The unique design of the pattern inversion was used,i.e.the SET pattern was transferred as a negative in an electron beam（e-beam） lithography step.The photoresist of the electron beam lithography was served as the mask in the dry etching,followed by the dry thermal oxidation and other processes.The method offers advantages of good accuracy,controllability,reproducibility and low cost,allowing for the SET fabrication in batch.The prepared SET exhibits strong Coulomb blockade effect at the temperatures from 2.6 K to 100 K.The on-resistance is less than 100 kΩ,which makes the SET advantageous to be the key device for the high speed and high sensitivity radio-frequency（RF） circuit.