Advantage Timely Energized Bubble Oscillation Megasonic Nano-Spray Method to Eliminate Surface Particle Defect in Lightly Doped Drain 28NM

After lightly Doped Drain (LDD) photoresist wet strip, the random surface particles were often detected by wafer inspection, especially in the 28 nm IC technology and beyond. Sensitive pattern structures were very easily damaged by traditional violent clean, therefore it was more difficult to remove random defects completely within LDD loop. In this study, an advantage Timely Energized Bubble Oscillation Megasonic Nano-spray (TEBO Nano-spray) wet clean method was introduced to remove unwanted surface particle defect within LDD loop in a single wafer clean tool. Remarkable particle remove efficiency (PRE) was as high as 90 % with pattern damage free by using the new wet clean method. At the same time the device reliability was qualified. The cleaning condition and related substrate loss were also taken into consideration.