Plasma etching apparatus and plasma etching method

摘要

A plasma etching apparatus 11 includes a mounting table that holds a semiconductor substrate W thereon; a first heater 18a that heats a central region of the semiconductor substrate W held on the mounting table 14; a second heater 18b that heats an edge region around the central region of the semiconductor substrate W held on the mounting table 14; a reactant gas supply unit 13 that supplies a reactant gas for a plasma process toward the central region of the semiconductor substrate W held on the mounting table 14; and a control unit 20 that performs a plasma etching process on the semiconductor substrate W while controlling the first heater 18a and the second heater 18b to heat the central region and the edge region of the processing target substrate W held on the mounting table 14 to different temperatures.

主权项

1. A plasma etching apparatus comprising:
a processing chamber that performs therein a plasma process on a processing target substrate; a mounting table that is provided within the processing chamber and holds the processing target substrate thereon; a first heater that heats a central region of the processing target substrate held on the mounting table; a second heater that heats an edge region around the central region of the processing target substrate held on the mounting table; a microwave generator that generates a microwave for plasma excitation; a dielectric plate that is provided at a position facing the mounting table and introduces the microwave generated by the microwave generator into the processing chamber; a reactant gas supply unit that supplies a reactant gas for a plasma process toward only the central region of the processing target substrate held on the mounting table; and a control unit that performs a plasma etching process on the processing target substrate while controlling the first heater and the second heater to heat the central region and the edge region of the processing target substrate held on the mounting table to different temperatures, wherein a CD (Critical Dimension) bias at the edge region of the processing target substrate is affected by a reaction product generated by the plasma etching process performed on the central region of the processing target substrate, and the control unit is configured to control the first heater and the second heater in consideration of the reaction product, such that a CD bias at the central region of the processing target substrate and the CD bias at the edge region of the processing target substrate are substantially the same, wherein the reactant gas supply unit is located in an upper recess formed in an upper surface of the dielectric plate, with a bottom surface of the reactant gas supply unit being recessed from a bottom surface of the dielectric plate, such that a processing space between the processing target substrate and the dielectric plate is extended to the bottom surface of the reactant gas supply unit recessed from the bottom surface of the dielectric plate, and a sealing member is provided between a bottom surface of the reactant gas supply unit and an upper surface of a part of the dielectric plate supporting the reactant gas supply unit.