Measurement of cross-sectional potential of compound semiconductor heterostructures in vacuum condition by Kelvin probe force microscopy

摘要

Cross-sectional contact potential images of the GaAs pn junction and InAlAs/InGaAs layered structure's have been successfully obtained by Kelvin probe force microscopy (KFM) both in air condition and in vacuum condition. The results showed that the contact potential difference of these materials in vacuum condition were much higher than that in air condition. The spatial resolution of the present KFM was investigated by measuring the InAlAs/InGaAs layered structures with various thicknesses. The lateral resolution of contact potential was improved to be approximately 20 nm in vacuum condition.