Patent ID: 7682480

Claim:
An apparatus for etching a feature in an etch layer through a photoresist mask over a substrate, comprising: a plasma processing chamber, comprising: a chamber wall forming a plasma processing chamber enclosure; a substrate support for supporting a substrate within the plasma processing chamber enclosure; a pressure regulator for regulating the pressure in the plasma processing chamber enclosure; at least one electrode for providing power to the plasma processing chamber enclosure for sustaining a plasma; a gas inlet for providing gas into the plasma processing chamber enclosure; and a gas outlet for exhausting gas from the plasma processing chamber enclosure; a gas source in fluid connection with the gas inlet, comprising; an etchant source; a hydrogen containing gas source; and an at least one of a fluorocarbon and hydrofluorocarbon gas source; and a controller controllably connected to the gas source and the at least one electrode, comprising: at least one processor; and computer readable media comprising: computer readable code for conditioning the photoresist mask, comprising: computer readable code for providing a conditioning gas comprising a hydrogen containing gas with a flow rate from the hydrogen containing gas source and at least one of a fluorocarbon and a hydrofluorocarbon with a flow rate from the at least one of a fluorocarbon and hydrofluorocarbon gas source to the process chamber; and computer readable code for using the at least one electrode for energizing the conditioning gas to form the conditioning plasma; and computer readable code ramping the conditioning gas so that a ratio of the flow rate of the hydrogen containing gas and the flow rate of the at least one of the fluorocarbon and hydrofluorocarbon is ramped down; computer readable code for stopping the conditioning plasma; computer readable code for providing an etch plasma to the process chamber, wherein the etch plasma is different than the conditioning plasma; and computer readable code for etching a feature in the etch layer with the etch plasma.