Abstract: A system for reducing parasitic plasma in a semiconductor process comprises a first surface and a plurality of dielectric layers that are arranged between an electrode and the first surface. The first surface and the electrode have substantially different electrical potentials. The plurality of dielectric layers defines a first gap between the electrode and one of the plurality of dielectric layers, a second gap between adjacent ones of the plurality of dielectric layers, and a third gap between a last one of the plurality of dielectric layers and the first surface. A number of the plurality of dielectric layers and sizes of the first gap, the second gap and the third gap are selected to prevent parasitic plasma between the first surface and the electrode during the semiconductor process.

Abstract: Apparatus and methods to minimize wafer-to-wafer process variation in RF-based semiconductor processing reactors with shared RF source for multiple processing areas. RF sensors associated with each processing area sends signal to the RF balance controller. The controller modifies station impedance using power adjustment mechanisms. As a result, station to station distribution of a selected RF parameter (e.g., load power) may match the station set points. Closed loop control maintains balance despite changing conditions.

Abstract: Methods and hardware for generating variable-density plasmas are described. For example, in one embodiment, a process station comprises a showerhead including a showerhead electrode and a substrate holder including a mesa configured to support a substrate, wherein the substrate holder is disposed beneath the showerhead. The substrate holder includes an inner electrode disposed in an inner region of the substrate holder and an outer electrode being disposed in an outer region of the substrate holder. The process station further comprises a plasma generator configured to generate a plasma in a plasma region disposed between the showerhead and the substrate holder, and a controller configured to control the plasma generator, the inner electrode, the outer electrode, and the showerhead electrode to effect a greater plasma density in an outer portion of the plasma region than in an inner portion of the plasma region.

Abstract: A plasma-enhanced chemical vapor deposition (PECVD) process including plasma particle extraction is described. Charged particles suspended in discharge volume are moved together with a plasma and can then be flushed away. The particle extraction process reduces unwanted particles on the wafer after deposition and reduces total process time. In some embodiments, the process can involve powering an electrode in the process chamber located away from the wafer. This electrode can be powered up as the main deposition electrode is powered down.