Abstract: An improved GaAs MESFET includes a source contact ohmically coupled to a buffer layer or substrate to stabilize band bending at the interface of the active layer and buffer layer or substrate when an RF signal is applied to a gate electrode.

Abstract: An improved GaAs MESFET includes a source contact ohmically coupled to a buffer layer or substrate to stabilize band bending at the interface of the active layer and buffer layer or substrate when an RF signal is applied to a gate electrode.

Abstract: There is disclosed a method of making an LED array head capable of simplifying an electrical wiring arrangement process between an individual electrode of each LED component and an external wiring upon formation of the LED array on a ceramic substrate. The inventive method includes the steps of: forming an external wiring on a portion of top surface of a substrate having a recess and an internal wiring on an entire top surface of said recess; bonding a respective LED component into said recess; forming an insulating film on the entire top surface of the substrate and the LED component; forming contact windows by selectively etching said insulating film so as to make access to the external wiring and an individual electrode disposed on the top surface of said LED component; and forming secondary wiring for electrically coupling the individual electrode with the external electrode through said contact windows.

Abstract: A monolithic laser diode and photo diode is provided in a process in which a mesa is formed on a substrate, the mesa including two regions having different upper surface widths. A photoactive layer serving eventually as the active layer of the laser diode and the light detecting layer of the photo diode is formed on the mesa by means of a liquid phase epitaxy process in which the rate of growth of the layer is faster on the mesa region of greater surface width. This results in different layer thicknesses on the two mesa regions. The region with the thinner layer is thereafter incorporated into the laser diode, and the region with the thicker layer is incorporated into the photo diode. The thicker photo diode layer enhances the light capturing capacity of the photo diode.