半导体外延掺杂的深度分布——“修正的”余误差分布  

Impurity Concentration Profile in Doped Semiconductor Epitaxial Layer:"Modified" Complementary Error Function

作　　者：杨恒青[1] 宋毅锋[1] 

机构地区：[1]复旦大学材料科学系,上海200433

出　　处：《复旦学报（自然科学版）》2008年第1期8-13,共6页Journal of Fudan University：Natural Science

摘　　要：在制造半导体器件的外延工艺中,外延生长时通常要掺入杂质.如果杂质的扩散系数很小,杂质在外延层中的深度分布是均匀的;如果杂质的扩散系数较大,半导体在外延生长过程中,杂质还有较明显的扩散,也会扩散到衬底中去.杂质浓度随深度分布不仅和杂质的扩散系数有关,还和外延生长速度及外延生长时间有关.从理论上推导出掺杂外延生长时杂质浓度深度分布表达式——"修正的"余误差分布;并根据该表达式绘出不同扩散系数和不同外延生长条件下的杂质浓度深度分布图;讨论了由杂质浓度深度分布确定扩散系数的实验条件.During epitaxy growth impurity atoms will diffuse in the epitaxial layer, even though it into the substrate. The impurity concentration profile depends on the speed of epitaxy growth,growth time and impurity diffusion ooeffident. The expression of irapurity concentration profile-＂modified＂complementary error function is theoretically derived. Then the impurity concentration profiles are drawn for different diffusion coefficient,epitaxy growth speed and growth time. If the actual distribution of the impurity concentration in the epitaxial layer is measured by some technique, the impurity diffusion coefficient can be determined by fitting the measurement result with ＂modified＂complementary error function. The experiment conditions for determining the knpurity diffusion coeffident from the profile of impurity concentration are also discussed.

关 键 词：材料科学 半导体外延 杂质扩散 杂质浓度深度分布 

分 类 号：TN304.02[电子电信—物理电子学] TN304.054