When a 100 nm thick Si layer was transferred onto a bare Si wafer by the hydrogen-induced-layer-transfer process, a spongy damage layer with microvoids was formed on the transferred layer because of hydrogen blistering. The surface-to-volume ratio of the damage layer was greater than that of the layer where blistering did not occur. Therefore, the damage layer was selectively etched by an HF/H(2)O(2) mixture and completely removed (the etching rates of Si at 70 degrees C for the bulk layer and damage layer were 0.45 and 13.8 nm/min, respectively). Consequently, a smooth, damage-free Si layer (root-mean-square roughness = 2.74 nm) was obtained. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3397476] All rights reserved.