Patent ID: 9464352
Filing Date: 2016-10-11
CPC Classification: C23C,H01J,H01L

Claim Text:
1. A method for forming an oxide film by plasma-assisted cyclic processing, comprising: (i) supplying a precursor to a reaction space wherein a substrate is placed; (ii) applying a first RF power to the reaction space for a first period of time without supplying a precursor; and (iii) applying a second RF power to the reaction space for a second period of time without supplying a precursor, wherein the first RF power is lower than the second RF power, and/or the first period of time is shorter than the second period of time, wherein the first RF power is no more than 0.14 W/cm wherein the oxide film is constituted by a first oxide layer and a second oxide layer, wherein steps (i) and (ii) without step (iii) constitute a first cycle, and by repeating the first cycle, the first oxide layer is formed on the substrate, and wherein steps (i) and (iii) without step (ii) constitute a second cycle, and by repeating the second cycle, the second oxide layer is formed on top of the first oxide film, said precursors used in the first and second cycles being the same, wherein step (ii) is controlled so that the first oxide layer has a film profile showing a thickness of the first oxide layer which is thicker at a center of the first oxide layer than along a periphery of the first oxide layer, and step (iii) is controlled so that the second oxide layer has a film profile showing a thickness of the second oxide layer which is thicker along a periphery of the second oxide layer than at a center of the second oxide layer.