Abstract: The disclosed hybrid microlens enables the economical production of large diameter, high numerical aperture refractive microlens by microfabrication. The hybrid microlens has a combination of a refractive microlens formed on a thin layer of high index material such as silicon and a spacer layer of a low index material such as fused silica. Advantages include substantially reduced lens sag, fast etching of the microlens, small wafer stack thickness, large diffraction angle in the low index spacer, large optical beam diameter, high optical performance, and low cost. Also disclosed is a design for substantially reduced optical return signal and small polarization dependent optical loss from an optical fiber which is perpendicular to and butt-coupled to a planar optical surface. This design is to form a small slanted surface on the planar optical surface in the vicinity of the optical fiber core and fill the space between the fiber and the slanted surface with an index-matching optical epoxy.

Abstract: A hybrid deposition system includes a reactor chamber, at least one heating unit, a first reagent gas source, a metallo-organic source, a second reagent gas source, and a valve unit for stopping flow of gas from the metallo-organic source. The hybrid incorporates features of both metal-organic chemical vapor deposition (MOCVD) and hydride vapor-phase epitaxy (HVPE). The hybrid system may be operated in MOCVD mode, in HVPE mode, or in both MOCVD and HVPE mode simultaneously. The system may be switched between deposition modes without interrupting deposition, or removing the sample from the reactor chamber. The at least one heating unit may be moved relative to the reactor chamber, or vice versa, for easily and rapidly adjusting the temperature of the reactor chamber. A method for forming at least one epitaxial layer of a III-V compound on a non-native substrate in which deposition is performed by two different techniques in the same reactor chamber.