Patent ID: 9093607
Filing Date: 2015-07-28
Classification: B82Y,H01L,Y10S

Abstract:
1. A light-emitting diode comprising: a plurality of nanowires formed directly on a substrate, said nanowires being made of an unintentionally doped semiconductor material, wherein said nanowires form an active semiconductor area, along an entire height of each of said nanowires, for radiative recombination of electron-hole pairs; a continuous first semiconductor area for radially injecting holes into each of said nanowires and partially coats a portion of each of said nanowires opposite to said substrate without contacting said substrate, said continuous first semiconductor area being made of a doped semiconductor material having a first conductivity type and having a bandgap that is greater than a bandgap of the unintentionally doped semiconductor material forming said nanowires; and a second semiconductor area for axially injecting electrons into each of said nanowires, said second semiconductor area being made of a doped semiconductor material having a second conductivity type that is opposite to that of the first conductivity type; an upper ohmic electrode formed on the continuous first semiconductor area and a lower electrode formed in contact with the substrate; wherein the active semiconductor area for the radiative recombination of electron-hole pairs is made of a single semiconductor material; wherein the single semiconductor material of the active semiconductor area for the radiative recombination of electron-hole pairs is one of a III-V type semiconductor material, a II-VI type semiconductor material and a III-N type semiconductor material: wherein the continuous first semiconductor area for radially idectin holes is formed of p-doped GaN or p-doped InGaN; wherein the second semiconductor area for axially injecting electrons is formed of n-doped Si or n-doped GaN; and wherein the height of the active semiconductor area for the radiative recombination of electron-hole pairs has a minimum value determined according to the following relationship: wherein F is the nanowire filling factor, J overflow is the maximum current density withstood by said nanowires with no electron saturation, N C is the effective density of states of the conduction band of the nanowire material, e is the elementary charge. B is the bimolecular recombination coefficient of the nanowire material, and W DH is the minimum value of the height of the active semiconductor area, and the height of the active semiconductor area for the radiative recombination of electron-hole pairs of said nanowires ranges between 40 nanometers and 5 micrometers.