【摘要】 利用真空Kelvin探针力显微镜(KFM)研究了纳米尺度下n-AlGaN/GaN薄膜的表面电荷性质并进行了定量测量.结果表明,n-AlGaN/GaN薄膜的表面位错均为电活性的受主型表面态,所捕获电荷的区域远远大于表面位错的大小,其表面电势与GaN薄膜表面电势的最大差值达到590 mV.在光照下,n-AlGaN/GaN薄膜的表面电荷发生了明显的光生电荷重新分布现象.更多还原

【Abstract】 The surface charge characteristics of n-AlGaN/GaN heterostructures films in nano-scale were studied by means of Kelvin probe force microscopy(KFM) technique in vacuum.The results show that all the dislocations of n-AlGaN/GaN heterostructures films are negatively charged,and the maxinum contact potential difference between the dislocations and GaN is about 590 mV.Moreover the contact potential variations around the dislocations in n-AlGaN/GaN heterostructures films is much larger than that of dislocations in diameter.The photo-generated charges rediscontribution was observed under illumination.This result indicates that surface charges of semiconductor in nano-scale can be measured quantitatively by KFM in vacuum condition.更多还原