標準機械化介面之晶圓微塵減量研究

Abstract

隨著半導體製程技術已經進入到奈米世代，相對地對於污染微塵粒子要求愈來愈嚴格，標準機械化介面(Standard Mechanical Interface ; SMIF)為八吋晶圓廠晶片載卸設備主流，此設計主要為了隔絕污染粒子進入到微環境，以避免污染晶片。 本研究主要探討如何降低SMIF微環境中，晶片載卸動作過程所發生微塵掉落問題。透過田口方法設計出最佳製程參數，並利用此結果進行微調和晶舟盒支架材質改變，使得SMIF微環境可以控制在更良好的潔淨度，以降低晶片被污染的機率，進而提昇產品品質與良率。

本論文研究成果彙整如下: 1.晶舟盒當中的固定支架材質為微塵污染主要來源之一，PEEK材質支架品質較PC材質支架良好，而污染粒子發生機制是發生於晶片載卸過程當中所必然的摩擦。 2.SMIF微環境中氣流與風壓為重要影響因子，經實驗驗證SMIF內部機械參數由原本的風速0.2m/s風壓300kPa調整為0.4m/s以及360kPa後可以大幅降低晶片異常率由原本6%~10% 至0.1%以下。 3.經過實驗驗證後結果顯示，最佳製程參數可以讓微環境保持在高潔淨度，以及降低晶片異常率。

Nowadays the semiconductor engineering technical has came to the nanometer generation, thus the demanding to the size of polluted particle has became strictly critical. Standard mechanical interface system is now the main stream in 8 inch wafer transferring device, This design is used for isolating the particle to pollute the mini-environment.

The main purpose of this research is to study the airflow’s effects on SMIF carrier module and to study the problem cause on the transferring process of wafer cassette. With the Taguchi methodology to get the best precise mechanical parameter and then to control well the cleanliness of the SMIF mini-environment and reduce the pollute rate on chips by the means of amend the device parameter and change the material of wafer lock from PC to PEEK.

The summary of this thesis : 1.The material of the wafer lock in the POD is the key point to anti-pollution and the material which made of PEEK can get the better quality than PC. It’s also the main pollution source when wafer lock touches the wafer edge in the movement of SMIF load/unload. 2.Air flow and wind pressure are the main factors to affect the mini-environment. Through the verification of the experiments, they affirm that can control the cleanness level in a certain way and reduce the rate of abnormal production by adjusting the SMIF parameter from 0.5m/s and 300kPa to 0.4m/s and 360kPa. Which also could reduce the failure rate of the chip production from 6%~10% to 0.1% such brilliant figure.

3.Through the validation of our experiment design, the results show the best set of mechanical parameter can keep the mini-environment in the highest cleanliness and reduce failure rates of processing wafers.