Abstract: Methods and apparatus for reducing autodoping and backside defects on a substrate during epitaxial deposition processes are provided herein. In some embodiments, an apparatus for reducing autodoping and backside defects on a substrate includes a substrate support ring having a substrate holder structure configured to support the substrate in a position for processing along an edge defined by the backside of the substrate and a sidewall of the substrate or along a plurality of discrete points on or proximate to the edge; and a spacer ring for positioning the substrate support ring above a susceptor plate to define a substrate gap region between the susceptor plate and the backside of the substrate, the spacer ring comprising a plurality of openings formed therethrough that facilitate passage of a gas into and out of the substrate gap region.

Abstract: An epitaxial reactor enabling simultaneous deposition of thin films on a multiplicity of wafers is disclosed. During deposition, a number of wafers are contained within a wafer sleeve comprising a number of wafer carrier plates spaced closely apart. Process gases flow preferentially into the interior volume of the wafer sleeve, which is heated by one or more lamp modules. To improve uniformity, the direction of process gas flow may be varied in a cross-flow configuration and the wafers may be mounted at a small angle to the plane of the wafer carrier plates, wherein the wafers are configured in pairs along the direction of gas flow and wherein along the direction of gas flow the angular mounting of the wafers provides a smaller gap between opposed wafer surfaces on said parallel wafer carrier plates in the center of said wafer sleeve than at the periphery of said wafer sleeve.

Abstract: A pedestal positioning assembly system for use in a substrate processing system includes a pedestal rigidly attached to a pedestal shaft, a reference rigidly attached to the substrate processing system, a lateral adjustment assembly to adjust a lateral location of the pedestal relative to the reference, and a vertical adjustment assembly to adjust a tilt of the pedestal relative to the reference. The lateral adjustment assembly and the vertical adjustment assembly are external to a processing chamber and are coupled to the pedestal disposed within the processing chamber through the pedestal shaft. The reference can be a ring and the lateral adjustment assembly substantially centers the pedestal within the ring. A method of adjusting a pedestal includes leveling the pedestal, translating the pedestal, calibrating the pedestal height to a preheat ring level, and checking the level and location of the pedestal while rotating the pedestal.

Abstract: Methods and apparatus for reducing autodoping and backside defects on a substrate during epitaxial deposition processes are provided herein. In some embodiments, an apparatus for reducing autodoping and backside defects on a substrate includes a substrate support ring having a substrate holder structure configured to support the substrate in a position for processing along an edge defined by the backside of the substrate and a sidewall of the substrate or along a plurality of discrete points on or proximate to the edge; and a spacer ring for positioning the substrate support ring above a susceptor plate to define a substrate gap region between the susceptor plate and the backside of the substrate, the spacer ring comprising a plurality of openings formed therethrough that facilitate passage of a gas into and out of the substrate gap region.

Abstract: The invention pertains to a method for the selective etching of a surface layer which is automatically stopped at a subjacent layer.According to the invention, a first layer of a material containing gallium is selectively etched with respect to a second layer containing aluminium by reactive ion etching in the presence of a pure freon plasma C Cl.sub.2 F.sub.2. At low pressures (0.5 to 2.5 pascals), the etching is anisotropic and makes it possible to etch the gate recess of a field effect transistor. At a higher pressure (6 to 10 pascals), the etching is isotropic and makes it possible to sub-etch the first layer.Application to the manufacture of field effect transistors made of group III-V materials, with low access resistances.