I used to grow materials using UHVCVD on Si wafer. To prepare the wafer, we usually did RCA cleaning followed by N2 spin dry. And the growth was successful. Recently, we want to try some growth on Si/Ge pieces, but have this surface preparation problem. The spin dry machine can only accept 4" or 6" wafer but not pieces. We tried to use N2 gun to blow the pieces after chemical treatment. But the result was not so good, especially on the peripheral part of the pieces due to the possible water residue on the edge. Do you guys have any experience on pieces sample growth and give some advices? Thank you very much!