Method to evaluate hemisperical grain (HSG) polysilicon surface
 A new method based on measuring the weight of a wafer (on which the layer of HSG has been deposited) before (W1) and after (W2) the surface of the HSG layer is coated with a layer of either photoresist or SOG. The difference delta W=W2-W1 provides an indicator of the roughness or smoothness of the surface of the deposited layer of HSG. This new method can also be based on measuring the weight W of rejected or dropped PR or SOG after the surface of the HSG layer has been coated with a layer of either photoresist or SOG. The weight of the rejected or dropped PR or SOG also provides an indicator of the roughness or smoothness of the surface of the deposited layer of HSG. 
Taiwan Semiconductor Manufacturing Company
H
H01L
inventional
Kuo-Ching Yu-Hua Tse-Liang Wen-Chuan
Huang Lee Ying Chiang