Results from evaluation of an immersion type single wafer cleaning tool were reported for 65nm process integration flow. This single wafer tool uses three megasonic transducers and Enhanced Marangoni Dry Technologies to address device damage and watermark issues. It has been found that the interaction between the three megasonic transducers play a major role in providing a damage-free cleaning process. With optimized megasonic configuration, damage free cleaning with corresponding particle removal efficiency (PRE) above 90% has been achieved with 65 nm gate poly-Si lines. Watermark-free performance has also been achieved for various device structures including STI and S-Poly. In addition, etch studies were conducted to evaluate the etch uniformity for ultra thin oxide removal. Sub-A level precision has been obtained for -10 A and -20 A thermal oxide etch with 3% and 1% etch uniformity [(Max-Min)/2*average]. Finally, results from metal cross contamination studies are also presented.
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