聚胺酯/石墨之拋光墊應用於化學機械研磨移除晶圓氧化層特性之研究

A Study On The Quality In Polyurethane/Graphite Pad Applied For Chemical Mechanical Polishing Oxide Film Of Wafer

陳秋元(Chiu-Yuan Chen)

指導教授 ： 徐開鴻 ； 蔡明義

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2011年)

摘要

化學機械拋光(Chemical mechanical polishing or planarization; CMP)為半導體製程中唯一可達到全區域平坦化的關鍵技術。
目前應用於化學機械拋光製程中的拋光墊，皆以聚胺酯(Polyurethane)發泡型高分子為主，因其發泡結構使得拋光墊表面佈滿孔洞可儲存研磨液，但也因孔洞直徑大小不一致，造成研磨液消耗過度；故本研究在聚胺酯高分子中添入兩種微米級(60μm)石墨粉末，成型後製成無孔型石墨拋光墊(No porous Graphite Pad)並搭配傳統鑽石碟(DG329)對晶圓氧化層(Oxide)進行化學機械研磨及機械性質之探討；添入60微米的石墨粉末之目的在於，石墨具備潤濕性質，可使研磨液充分的潤濕拋光墊表面，使之磨粒均勻的分佈於拋光墊上，有助於晶圓氧化層之移除。實驗結果顯示添加石墨之拋光墊移除率皆比未添加的拋光墊來得高，且晶圓氧化層表面的均勻性也較佳。

關鍵字

化學機械研磨 ； 鑽石修整器 ； 晶圓氧化層 ； 聚胺酯

並列摘要

In Chemical mechanical polishing (CMP) field, Polyurethane materials is widely use on polishing pad, because it have porous can save the slurry, but easy cause glazing, because the porous size is not average.
In this study, we add two micron (60μm) of graphite powder in the polyurethane polymer, one is the natural graphite; the other for the hydrogenation of natural graphite after heat treatment, both in polymer addition level of 0%, 8%, 16 %, 24%, after forming polishing pad made of graphite-free pass (No porous Graphite Pad) and with the conventional diamond disk (DG329) on the wafer oxide, and discuss chemical mechanical polishing and mechanical properties.
The experimental results showed that the Hydrogenated graphite pad is not removed more than highly hydrogenated graphite pad, and the wafer surface after removal of oxide layer uniformity are increasing. So we suggestion 8% addition of hydrogenated graphite oxide can achieve the best performance on the removal rate and uniformity.

並列關鍵字

chemical mechanical polishing ； diamond conditioner ； wafer oxide layer ； polyurethane

參考文獻

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