Structural and transport characterization of AlGaAs/GaAs quantum wires formed by selective doping mechanism

摘要

We have fabricated the lateral n-i-p-i heterojunction quantum wire structures by utilizing the selective doping mechanism of amphoteric silicon dopant by molecular beam epitaxy.The quantum wire structure was investigated by electrostatic force microscope (EFM) and the electrical transport properties were investigated by magnetoresistance characteristics and the field effect quantum wire transistor characteristics.The EFM measurements revealed that the estimated quantum wire width to be approx approx 800A which was consistent with the estimation based on Shubnikov-de Haas oscillations.Effective electron mobilities of the quantum wire were estimated to be 4,900cm~2/Vs,16,300cm~2/Vs,15,700cm~2/Vs at room temperature,80K,and 2.1Krespectively,based on transistor characteristics.These high-field results suggest that the reasonably high quality quantum wire can be obtained using present method of selective doping.