Hi, All, I need to obtain a uniform layer of random pyramids on the (100) mirror-polished Si surface. I have been trying the NaOH (1-3%) + Ethyl Glycol(0.6%) + Isopropanol (5-10%) at 78 C. Here is my questions: 1. I have already HF the sample just before the etch, so that it is hydrophobic. But I found out that more often than not, it does not etch. Or it just etches part of the sample. My samples ranges from 2x2cm to 5x5cm. 2. I have found out that if I RCA clean the sample before the NaOH etch, it is harder to etch the sample. 3. If I use some diamond paste (for polishing) with grit size ranging from 3 - 9 um to rub the sample surface, the etch begins right away. Anybody with experience in texture etching the (100) silicon surface with NaOH? Thanks! Dave