Abstract: A beam expander for providing coupling between a semiconductor optical device and an optical fiber comprises a double layer structure that may be integrated with the optical device. The first, underlying layer of the expander comprises a relatively high refractive index material (e.g., 3.34), thus providing improved coupling efficiency between the optical device and the fiber. The second, covering layer of the expander comprises a relatively low refractive index material (e.g., 3.28), for providing the large mode size desired at the fiber input. The parameters of each layer can be adjusted independently, allowing for the two criteria (coupling efficiency and mode size) to be separately optimized.

Abstract: A beam expander for providing coupling between a semiconductor optical device and an optical fiber comprises a double layer structure that may be integrated with the optical device. The first, underlying layer of the expander comprises a relatively high refractive index material (e.g., 3.34), thus providing improved coupling efficiency between the optical device and the fiber. The second, covering layer of the expander comprises a relatively low refractive index material (e.g., 3.28), for providing the large mode size desired at the fiber input. The parameters of each layer can be adjusted independently, allowing for the two criteria (coupling efficiency and mode size) to be separately optimized.

Abstract: A bond pad having reduced capacitance is disclosed which is useful in fabricating integrated circuit and communications devices. The bond pad is disposed within a select bond pad area and comprises a ribbon of conductive material within the select pad area and a two-phased region of air and conductive material. Also, at least one interconnect area is disposed within the bond pad area. The ribbon is coupled to the two-phased region, and the interconnect is coupled to the ribbon and to the device. Inclusion of air within the bond pad structure reduces the capacitance of the device, while the surface area of the bonding pad is maintained to at least substantially retain the adhesive properties of the pad.

Abstract: A stable, reliable ohmic contact, and improved semiconductor articles and opto-electronic circuits incorporating same, are disclosed. According to an illustrative embodiment of the invention, an ohmic contact having a plurality of thermodynamically-stable layers and layer interfaces is formed by providing a structure comprising multiple, appropriately-thick and specifically-organized layers of suitably-selected material, and exposing the structure to heat to cause reaction to take place between the various layers. Due to the thermodynamic stability of the resulting reacted layers and the interfaces between such layers, there is substantially no tendency for further reaction to occur within the ohmic contact.