摘要
用液结光伏谱方法首次在ＰＮ４３５０光伏谱仪上对用国产ＭＯＣＶＤ设备生长的九个ｐ－ＧａＡｓ／ｎ－ＧａＡｓ外延样品ｐ型外延层的少于扩散长度Ｌｎ和掺杂浓度ＮＡ的关系作了测量和分析．结果表明，Ｌｎ－ＮＡ关系对反应管的清洁度非常敏感．如果反应管经严格清洗，并仅生长ＧａＡｓ材料，那么Ｌｎ－ＮＡ关系同前人报道的无沾污生长的样品基本一致；否则Ｌｎ值就明显偏小．用本方法测定ＧａＡｓ外延层的Ｌｎ值具有简便、准确的优点，可作为检测ＧａＡｓ外延层质量的重要手段．
Abstract in this paper, the relation of the minority carrier diffusion length Ln to acceptor doping concentration NA in p-type epilayer of 9 p-GaAs/n-GaAs samples grown by Chinese-made MOCVD system was measured and analyzed with the PN4350 liquid junction photovoltage spectrometer for the first time. The results show that Ln-NA relation is highly sensitive to the cleanliness of MOCVD chemical reaction tube. If the chemical reaction tube was washed carefuly and only GaAs was grown in it, the Ln-NA relation is in agreement with reported results in references. Otherwise, the Ln is shorter notably. This method of the measuring Ln for GaAs epilayer is simple, convenient and accurate. It is important for testing the quality of the GaAs epilayers.
