半導體淺溝槽內之矽筍狀缺陷去除

Abstract

淺矽溝槽製程(Shadow Trench Isolation Process)正是做為半導體製程中 隔離電晶體開與關的功能,但是在製造過程當中遇到缺陷(Defect)便會影響到產品的穩定性(Reliability)及品質(Quality),這次論文要探討的就是淺矽槽製程中的其中一種缺陷---矽筍狀缺陷(Silicon Nodule Defect). 矽筍狀缺陷是一種存在於淺矽槽中的缺陷,當淺矽溝槽製程要將電晶體的主動區(Active-Area)與非主動區(Non Active-Area)隔開的同時,因為在蝕刻淺矽溝槽的過程當中,越深的矽槽中的生成反應物(by product)太多而不容易被真空幫浦(Vacuum Pump)抽走,隨著非等向性蝕刻(Anisotropic Etching)而形成矽筍狀缺陷.蝕刻淺矽槽的主要蝕刻氣體為溴化氫(Hydrogen Bromide; HBr)及六氟乙浣(Hexafluoroethane;C2F6),利用其在淺矽槽製程中提供的等向性蝕刻的離子轟擊(Ion Bombardment),由於在較深的淺矽槽中的生成反應物太多,試著降低HBr與C2F6的蝕刻氣體的比例(Etching Gas Ratio),可以消除矽筍狀缺陷.

Shallow trench silicon as the semiconductor manufacturing process is the process of isolation transistors on and off the function, but experience in the manufacturing process to product defects will affect the stability and quality,this paper is to explore shallow silicon trench process in which a defect in the nodule-like defects in Si ---. Si shoots like a flaw exists in the shallow defects in silicon slot, when the shallow trench process silicon transistor to the active region and separated at the same time non-active area because in the shallow silicon trench etching process, the deeper the generation of silicon reactant tank is not easy to be too much take away the vacuum pump, with the formation of anisotropic etching of silicon nodule-like defects. etching shallow silicon etching gas for the main tank of hydrogen bromide (HBr) and Hexafluoroethane (C2F6), using its process in a shallow groove in the silicon anisotropic etching to provide non-ion bombardment, as in the deeper formation of shallow silicon reactant tank too much, try HBr and C2F6 reduce the proportion of the etching gas, nodule-like defects in silicon can be Eliminated.