Photoresist mask-free oxide define region (ODR)

摘要

Defining an oxide define region (ODR) without using a photomask is disclosed. Pad oxide and a stop layer are deposited over peaks of a substrate of a semiconductor wafer. The pad oxide may be silicon oxide, whereas the stop layer may be silicon nitride. Oxide, such as high-density plasma (HDP) oxide, is deposited over the pad oxide, the stop layer, and valleys of the substrate of the semiconductor wafer. A hard mask, such as silicon nitride, is deposited over the oxide, and photoresist is deposited over the hard mask. The photoresist is etched back until peaks of the hard mask are exposed. The peaks of the hard mask and the oxide underneath are etched through to the stop layer, and the photoresist is removed. Chemical-mechanical planarization (CMP) can then be performed on the hard mask that remains and the oxide underneath through to the stop layer, and the stop layer removed.

主权项

1. A method for fabricating an oxide define region (ODR) without using a photolithographic-process photomask comprising:
depositing pad oxide and a stop layer over peaks of a substrate of a semiconductor wafer; depositing oxide over the pad oxide, the stop layer, and valleys of the substrate of the semiconductor wafer; depositing a hard mask over oxide; depositing photoresist over the hard mask; etching back the photoresist until peaks of the hard mask are exposed; etching the peaks of the hard mask and the oxide underneath the hard mask through to the stop layer; removing the photoresist; performing chemical-mechanical planarization (CMP) on the hard mask and the oxide underneath through to the stop layer; and, etching away the stop layer, resulting in the ODR on the substrate of the semiconductor wafer.