PULSED PLASMA CHAMBER IN DUAL CHAMBER CONFIGURATION

摘要

Embodiments for processing a substrate in a pulsed plasma chamber are provided. A processing apparatus with two chambers, separated by a plate fluidly connecting the chambers, includes a continuous wave (CW) controller, a pulse controller, and a system controller. The CW controller sets the voltage and the frequency for a first radio frequency (RF) power source coupled to a top electrode. The pulse controller is operable to set voltage, frequency, ON-period duration, and OFF-period duration for a pulsed RF signal generated by a second RF power source coupled to the bottom electrode. The system controller is operable to set parameters to regulate the flow of species between the chambers to assist in the negative-ion etching, to neutralize excessive positive charge on the wafer surface during afterglow in the OFF period, and to assist in the re-striking of the bottom plasma during the ON period.

主权项

1. A method for processing a wafer in a wafer processing apparatus with a top chamber and a bottom chamber, the method comprising:
setting first parameters for a continuous radio frequency (RF) signal generated by a first RF power source coupled to a top electrode in the top chamber, wherein the first parameters include a first voltage and a first frequency, the first RF power source configured to provide a continuous RF power during operation of the chamber; setting second parameters for a pulsed RF signal generated by a second RF power source coupled to a bottom electrode in the bottom chamber, wherein the second parameters include a second voltage, a second frequency, ON-period duration, and OFF-period duration, wherein a plate separates the top chamber and the bottom chamber, the plate having a plurality of holes that enable a flow of species from the top chamber to the bottom chamber during operation; applying the continuous RF signal to the top electrode; and applying the pulsed RF signal to the bottom electrode, wherein a bottom plasma is stricken in the bottom chamber during the ON period, wherein a potential of the bottom plasma decays during the OFF period until the potential reaches a value of substantially zero, wherein setting the first parameters and the second parameters regulates a flow of species from the top chamber to the bottom chamber during the ON period and regulates the flow of species during the OFF period, wherein regulating the flow of species assists in regulating negative-ion etching in the bottom chamber and regulating positive charge on a wafer surface in the bottom chamber during afterglow in the OFF-period, and regulating the flow of species assists in re-striking the bottom plasma in the bottom chamber during the ON period by regulating flow of electrons from the top chamber to the bottom chamber.