Title |
A Study on the Nitride Residue and Pad Oxide Damage of Shallow Trench Isolation(STI)-Chemical Mechanical Polishing(CMP) Process |
Authors |
이우선(Lee, U-Seon) ; 서용진(Seo, Yong-Jin) ; 김상용(Kim, Sang-Yong) ; 장의구(Jang, Ui-Gu) |
Keywords |
STI(shallow trench isolation) ; CMP(chemical mechanical polishing ) ; nitride residue, pad oxide damage ; within- wafer- non-uniformity(WIWNU) ; reverse moat etch |
Abstract |
In the shallow trench isolation(STI)-chemical mechanical polishing(CMP) process, the key issues are the optimized thickness control, within-wafer-non-uniformity, and the possible defects such as pad oxide damage and nitride residue. The defect like nitride residue and silicon (or pad oxide) damage after STI-CMP process were discussed to accomplish its optimum process condition. To understand its optimum process condition, overall STI related processes including reverse moat etch, trench etch, STI fill and STI-CMP were discussed. Consequently, we could conclude that law trench depth and high CMP thickness can cause nitride residue, and high trench depth and over-polishing can cause silicon damage. |