| abstract |
PROBLEM TO BE SOLVED: To improve a side wall shape of a contact via formed by etching a dielectric layer, and to maintain a state of a process chamber in a state of reducing undesirable residues and polymer by-products. Following a dielectric etching process of a semiconductor structure having an upper dielectric layer with openings formed by etching, the semiconductor structure is reacted with oxygen, a nitrogen-containing gas, and a reactive gas comprising hydrogen, carbon and fluorine. Exposure to plasma generated from the gas. |