Abstract: Apparatus for semi-sealed diffusion of semiconductor materials includes a quartz tube with a quartz stopper at one end to facilitate the loading and unloading of semiconductor materials, the other end of the quartz tube having an inlet passage with a quartz stopcock. The stopper includes quartz pressure release valve.The process involves loading semiconductor material to be diffused into the tube with a source of diffusion. The semiconductor material, e.g., in the form of wafers, is first coated with an oxide layer. The stopper is inserted to seal the tube, the interiors being then purged with an inert gas supplied to the inlet passage which is subsequently closed prior to placing the tube in a furnace to initiate the diffusion process. After diffusion, the ampoule is quenched, the stopper removed and the tube unloaded. The oxide layer is then stripped off revealing a diffused, damage-free surface.

Abstract: A luminescent solid state status indicator including at least first and second light emitting diodes of different colors which may be mounted on a single header. One side of each of the diodes is connected in common to one side of a source of energizing voltage subject to variation in magnitude. The other sides of the diodes are interconnected with the electrodes of a transistor which has one electrode connected to the other side of the DC energizing voltage. The transistor is adapted selectively to energize the first and second light emitting diodes to display colors corresponding respectively to discrete magnitudes of said energizing voltage.

Abstract: An integrated LED display array wherein light is emitted and observed through a light-transmissive substrate, i.e., single crystal, which carries a plurality of optically isolated LED assemblies. Scattering of light from individual assemblies is prevented by an optically absorbing doped region which optically isolates each assembly. Light is generated at the back of the single crystal and viewed through the crystal. The LED assemblies, preferably multicolor, are directly mated to energizing electronic circuitry, e.g., a monolithic integrated circuit, via appropriate interconnections sandwiched between the two. The energizing electronic circuitry comprise an array of circuit elements which provide the energizing currents for respective ones of the LED assemblies.