摘要
在p型硅 (10 0 )衬底上 ,采用衬底负偏压微波等离子体CVD方法进行了p型异质外延金刚石膜的生长 .用O2等离子体刻蚀技术将金刚石膜刻蚀成长条形 ,利用四探针法在 0— 5T的磁场范围内测量了样品的磁阻 .实验结果表明 ,p型异质外延金刚石膜可以产生较大的磁阻 .在Fuchs Sondheimer(F S)薄膜理论的基础上考虑晶格散射、杂质散射和表面散射 ,通过求解Boltzmann方程 ,利用并联电阻模型研究了p型异质外延金刚石膜的磁阻效应 ,给出了磁阻和金刚石膜厚度、迁移率、空穴密度及磁场的关系 .讨论了表面散射和价带形变对p型异质外延金刚石膜磁阻的影响 。
The heteroepitaxial diamond films were grown on the p-type Si (100) substrate by microwave plasma chemical vapor deposition (CVD). The diamond films were patterned to strip types with the oxygen plasma etching technology. The magnetoresistance measurements have been carried out in a magnetic field ranging from 0 to 5 T, using the four-probe method. It was shown that the heteroepitaxial diamond films may produce fairly big magnetoresistance. Based on the Fuchs and Sondheimer thin film theory I mixed scattering by lattice vibration, ionized impurities and surfaces is considered. Taking the parallel connection resistance model, a theoretical description of the magnetoresistive effect in heteroepitaxial diamond films is presented by solving the Boltzmann transport equation in the relaxation time approximation. A relationship between the magnetoresistance and the film thickness, magnetic field, mobility and hole density is developed. The influence of valence deformation and surface scattering to the magnetoresistance of heteroepitaxial diamond films is discussed. A possible cause is proposed to explain the fairly big magnetoresistance of the films.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2001年第8期1616-1622,共7页
Acta Physica Sinica
基金
国家自然科学基金 (批准号 :1990 40 16 )资助的课题&&
关键词
金刚石膜
异质外延
磁阻效应
电导率
半导体
diamond films
heteroepitaxial
magnetoresistive effect
conductivity
