Patent ID: 6133590
Filing Date: 2000-10-17
Classification: H01L,H01S

Abstract:
A semiconductor device comprising an active layer (4) of p-type or n-type material forming a junction with a first layer of doped n-type material (5), a second layer of doped n-type material (11) adjacent to a layer of doped p-type material (2), which may be adjacent to, or separated from by other layers, the active layer (4) of p-type or n-type material, and means for providing electrical contact with the device including means for providing electrical contact, via the second layer of doped n-type mater (11), with the adjacent layer of doped p-type material (2),wherein the second layer of doped n-type material (11) has a doping concentration of between 1.times.10.sup.18 cm.sup.-3 and less than 1.times.10.sup.19 cm.sup.-3 and in that the semiconductor energy band-gap of the active layer (4) is less than 0.5 eV and is transparent to radiation, of energy greater than that of the band-gap, which is emitted or absorbed by the device.