From transistors to light emitters

摘要

The report at the 1962 IRE Solid-State Device Research Conferencen(July, Durham, NH) of the generation and long-range transmission (andndetection) of a recombination-radiation signal from a simple Zn-diffusednGaAs p-n junction, a startling report, began the race to construct ansemiconductor laser. The visible-spectrum II-V alloy GaAs1-xPnx was in the middle of this activity and was (fall of 1962),nwith GaAs, a first semiconductor laser, not to mention the first lasernin a semiconductor alloy or crystal that could be “tuned” innenergy gap (and wavelength) from direct gap to indirect gap. The ternarynGaAs1-xPx, the prototype of all present-day III-Vnalloys used in heterojunction and quantum-well devices, establishednuniquely the importance of a direct gap for a laser and inevitably fornlight emitting diodes (LEDs). The events leading to the GaAs1-xnPx laser, as well as, in slightly different form, thenfirst practical LED, are described. The significance of the work ofn1962-1963 in launching the semiconductor laser is described, and thenreasons why the semiconductor laser (an “ultimate lamp”) isnpredominant over all other forms of lasers