Bottom-up PEALD process

摘要

The present disclosure relates to a method and apparatus for performing a plasma enhanced ALD (PEALD) process that provides for improved step coverage. The process introduces a precursor gas into a processing chamber comprising a semiconductor workpiece. The first gas is ionized to from a plurality of ionized precursor molecules. A bias voltage is subsequently applied to the workpiece. The bias voltage attracts the ionized precursor molecules to the workpiece, so as to provide anisotropic coverage of the workpiece with the precursor gas. A reactant gas is introduced into the processing chamber. A plasma is subsequently ignited from the reactant gas, causing the reactant gas to react with the ionized precursor molecules that have been deposited onto the substrate to form a deposited layer on the workpiece.

主权项

1. A plasma enhanced atomic layer deposition (PEALD) system, comprising:
a precursor gas inlet configured to provide a precursor gas into a processing chamber configured to house a semiconductor workpiece; a reactant gas inlet configured to provide a reactant gas into the processing chamber; an ionizing component configured to ionize the precursor gas to form a plurality of ionized precursor molecules and to subsequently ignite a plasma from the reactant gas, wherein the plasma causes a reaction between the ionized precursor molecules and the reactant gas that forms a deposited layer; a bias element configured to apply a bias voltage to the semiconductor workpiece that anisotropically attracts the ionized precursor molecules to the semiconductor workpiece; and a control unit configured to operate valves to introduce the precursor gas and the reactant gas into the processing chamber at non-overlapping, different time periods, and to send control signals that bias the semiconductor workpiece during ionization of the precursor gas and that subsequently ignite the plasma from the reactant gas.