以低壓有機金屬化學汽相磊晶法研究化合物半導體選擇性區域成長

Abstract

本論文中，我們利用低壓有機金屬化學汽相沉積法（Low-Pressure Metalorganic Chemical Vapor Deposition），以研究化合物半導體的選 擇性區域磊晶成長。作為研究對象的化合物半導體，包括：砷化鎵（GaAs ）、磷化鎵（GaP）、磷化銦（InP）及磷化銦鎵（GaInP）。 並使用不同 的三族材料組合作為成長磷化銦鎵的起始材料（precursors），這些材料 組合包括：三甲基鎵+三甲基銦（TMG+TMI）、 三甲基鎵+二甲基一乙基銦 （TMG+EDMI）、三乙基鎵+三甲基銦（TEG+TMI）、 三乙基鎵+二甲基一乙 基銦（TEG+EDMI）。並且，以外加調變材料的方式，探討四氯化碳(CCl4 ) 對選擇性的影響。為了解析區域成長範圍內的成份比例分佈，我們利高 解析雙單晶Ｘ射線繞射測量，並配合適當的成份分佈模型，可以合理地趨 近實際的成份分佈狀況。 We have done experimebtal studies on the epitaxial growth and selective epitaxial growth ( SEG ) of GaInP by low-pressure metalorganic chemical vapor deposition ( LP-MOCVD ) using ethyldimethylindium ( EDMI ), trimethylindium ( TMI ), trimethylgallium ( TMG ), and triethylgallium ( TEG ) as the group III sources. The selective epitaxial growth of GaInP on GaAs substrate patterned with silicon nitride is also done by LP-MOCVD. The group III sources employed are the combinations of TEG+EDMI, TEG+TMI, TMG+TMI and TMG+EDMI. A modified SEG using tetrachloride ( CCl4 ) as the additional source has been studied on the nucleation of GaAs, GaP, and InP on the SiNx surface. The selectivity can be improved by the additional Cl- containing reactants which is possessed of higher diffusion coefficients. By the HRXRD simulation, a proposed model for the composition variation in the SEG area is used to simulate the experiemntal results of the composition distribution in the SEG area. The model and simulation result can give s reasonable description for the composition distribution which is caused by the different diffusive characteristics of the precursor and its thermal-decomposed fragments.