Abstract:
Plasma immersion ion implantation employing a very high RF bias voltage on an electrostatic chuck to attain a requisite implant depth profile is carried out by first depositing a partially conductive silicon-containing seasoning layer over the interior chamber surfaces prior to wafer introduction.
Abstract:
A method for processing a workpiece in a plasma reactor chamber includes coupling RF power at a first VHF frequency f1 to a plasma via one of the electrodes of the chamber, and providing a center ground return path for RF current passing directly between the ceiling electrode and the workpiece support electrode for the frequency f1. The method further includes providing a variable height edge ground annular element and providing a ground return path through the edge ground annular element for the frequency f1. The method controls the uniformity of plasma ion density distribution by controlling the distance between the variable height edge ground annular element and one of: (a) height of ceiling electrode or (b) height of workpiece support electrode.
Abstract:
In a plasma reactor chamber a ceiling electrode and a workpiece support electrode, respective RF power sources of respective VHF frequencies f1 and f2 are coupled to either respective ones of the electrodes or to a common one of the electrodes, where f1 is sufficiently high to produce a center-high non-uniform plasma ion distribution and f2 is sufficiently low to produce a center-low non-uniform plasma ion distribution. Respective center ground return paths are provided for RF current passing directly between the ceiling electrode and the workpiece support electrode for the frequencies f1 and f2, and an edge ground return path is provided for each of the frequencies f1 and f2. The impedance of at least one of the ground return paths is adjusted so as to control the uniformity of the plasma ion density distribution.
Abstract:
A method is provided for processing a workpiece in a plasma reactor chamber having electrodes including at least a ceiling electrode and a workpiece support electrode. The method includes coupling respective RF power sources of respective VHF frequencies f1 and f2 to either (a) respective ones of the electrodes or (b) a common one of the electrodes, where f1 is sufficiently high to produce a center-high non-uniform plasma ion distribution and f2 is sufficiently low to produce a center-low non-uniform plasma ion distribution. The method further includes adjusting a ratio of an RF parameter at the f1 frequency to the RF parameter at the f2 frequency so as to control plasma ion density distribution, the RF parameter being any one of RF power, RF voltage or RF current.
Abstract:
Methods and apparatus for controlling characteristics of a plasma, such as the spatial distribution of RF power and plasma uniformity, are provided herein. In some embodiments, an apparatus for controlling characteristics of a plasma includes a resonator for use in conjunction with a plasma reactor, the resonator including a source resonator for receiving an RF signal having a first frequency; a return path resonator disposed substantially coaxially with, and at least partially within, the source resonator; and an outer conductor having the source resonator and the return path resonator disposed substantially coaxially with, and at least partially within, the outer conductor, the outer conductor for providing an RF ground connection.
Abstract:
Embodiments of sensor devices for characterizing magnetic fields formed in substrate processing systems and methods of use thereof are provided herein. In some embodiments, an apparatus for characterizing a magnetic field in a substrate processing system may include a carrier having a form substantially similar to a substrate to be processed in the substrate processing system. One or more magnetic sensors are disposed on the carrier for measuring a magnitude of a magnetic field formed in the processing system in an x-, y-, and z-direction. A microprocessor is coupled to the one or more magnetic sensors to sample data representative of the magnitude of the magnetic field in the x-, y-, and z-directions proximate a position of each sensor. A memory device is coupled to the microprocessor for storing the sampled data. A power source is provided to supply power to each magnetic sensor and the microprocessor.
Abstract:
A plasma reactor for processing a semiconductor workpiece includes a reactor chamber and a set of plural parallel ion shower grids that divide the chamber into an upper ion generation region and a lower reactor region, each of the ion shower grids having plural orifices in mutual registration from grid to grid, each orifice being oriented in a non-parallel direction relative to a surface plane of the respective ion shower grid. A workpiece support in the process region faces the lowermost one of the ion shower grids. A reactive species source furnishes into the ion generation region a chemical vapor deposition precursor species. The reactor further includes a vacuum pump coupled to the reactor region, a plasma source power applicator for generating a plasma in the ion generation region and a grid potential source coupled to the set of ion shower grids. The orifices through at least some of the ion shower grids have an aspect ratio sufficient to limit ion trajectories in the reactor region to a narrow angular range about the non-parallel direction, and a resistance to gas flow sufficient to support a pressure drop between the ion generation and reactor regions of about at least a factor of 4. The grid potential source can be capable of applying different voltages to different ones of the grids.
Abstract:
A method processing a workpiece in a plasma reactor chamber in which a first one of plural applied RF plasma powers is modulated in accordance with a time-varying modulation control signal corresponding to a desired process transient cycle. The method achieves a reduction in reflected power by modulating a second one of the plural plasma powers in response to the time-varying modulation control signal.
Abstract:
A process is provided for removing polymer from a backside of a workpiece. The process includes supporting the workpiece on the backside in a vacuum chamber while leaving at least a peripheral annular portion of the backside exposed. The process further includes confining gas flow at the edge of the workpiece within a gap at the edge of the workpiece on the order of about 1% of the diameter of the chamber, the gap defining a boundary between an upper process zone containing the wafer front side and a lower process zone containing the wafer backside. The process also includes providing a polymer etch precursor gas underneath the backside edge of the workpiece and applying RF power to a region underlying the backside edge of the workpiece to generate a first plasma of polymer etch species concentrated in an annular ring concentric with and underneath the backside edge of the workpiece.
Abstract:
A method and apparatus for removing excess dopant from a doped substrate is provided. In one embodiment, a substrate is doped by surfaced deposition of dopant followed by formation of a capping layer and thermal diffusion drive-in. A reactive etchant mixture is provided to the process chamber, with optional plasma, to etch away the capping layer and form volatile compounds by reacting with excess dopant. In another embodiment, a substrate is doped by energetic implantation of dopant. A reactive gas mixture is provided to the process chamber, with optional plasma, to remove excess dopant adsorbed on the surface and high-concentration dopant near the surface by reacting with the dopant to form volatile compounds. The reactive gas mixture may be provided during thermal treatment, or it may be provided before or after at temperatures different from the thermal treatment temperature. The volatile compounds are removed. Substrates so treated do not form toxic compounds when stored or transported outside process equipment.