Method for making a light-emitting microelectronic device with semi-conducting nanowires formed on a metal substrate
A process of making a microelectronic light-emitting device, including: a) growth on a metallic support of multiple wires based on one or more semi-conducting materials designed to emit radiant light, and b) formation of at least one electrical conducting zone of contact on at least one of the wires.
1. A method for making a light-emitting microelectronic device, the method comprising:
growing, on a continuous substrate metal layer having a thickness between 10 μm and 10 mm and belonging to a metal support, a plurality of wires based on one or plural semi-conducting materials, each wire being individually configured to emit light radiation and being formed of a first portion that is based on GaN and n-doped, said first portion being in contact with the continuous substrate metal layer, each wire being further formed of a second portion on said first portion, said second portion being a quantum well portion forming a light emitting active zone, and of a third portion on said second portion, said third portion being based on GaN and p-doped, wherein the continuous substrate metal layer reflects the light radiation emitted by the plurality of wires; and
forming at least one electrically conducting contact area on at least one of the wires.
2. The method for making a light-emitting microelectronic device according to claim 1 , wherein the substrate is a metal or a metal alloy comprising one of the following materials: iron, nickel, aluminum, silver, or copper.
3. The method for making a light-emitting microelectronic device according to claim 1 , further comprising, prior to the growing, depositing a catalyst material layer on the metal support.
4. The method for making a light-emitting microelectronic device according to claim 3 , wherein the catalyst material is gold or nickel.
5. The method for making a light-emitting microelectronic device according to claim 1 , further comprising, between the growing and the forming, forming an insulating layer for encapsulating the wires.
6. The method for making a light-emitting microelectronic device according to claim 5 , further comprising forming a transparent contact layer on the insulating layer so as to cover ends of the plurality of wires extending beyond the insulating layer.
7. The method for making a light-emitting microelectronic device according to claim 6 , wherein the transparent contact layer is electrically conducting.
8. The method for making a light-emitting microelectronic device according to claim 7 , wherein the transparent contact layer includes Ti and Au.
9. The method for making a light-emitting microelectronic device according to claim 7 , further comprising forming a contact point metal area on the contact layer.
10. The method for making a light-emitting microelectronic device according to claim 9 , further comprising forming a phosphor or luminophor material layer, that converts quasi mono-chromatic light into white light, on said contact point metal area and contact layer.
11. The method for making a light-emitting microelectronic device according to claim 1 , wherein the continuous substrate metal layer has a surface area of between 100 mm 2 and 1 m 2 .
12. The method for making a light-emitting microelectronic device according to claim 1 , further comprising degreasing the continuous substrate metal layer.
13. The method for making a light-emitting microelectronic device according to claim 12 , further comprising polishing the continuous substrate metal layer.
14. The method for making a light-emitting microelectronic device according to claim 1 , wherein each wire includes a fourth portion on said third portion, said fourth portion being based on GaN and p++ doped.
15. A method for making a light-emitting microelectronic device, the method comprising:
growing, on a continuous substrate metal layer having a surface area of between 100 mm 2 and 1 m 2 belonging to a metal support, a plurality of wires based on one or plural semi-conducting materials, each wire being individually configured to emit light radiation and being formed of a first portion that is based on GaN and n-doped, said first portion being in contact with the continuous substrate metal layer, each wire being further formed of a second portion on said first portion, said second portion being a quantum well portion forming a light emitting active zone, and of a third portion on said second portion, said third portion being based on GaN and p-doped, wherein the continuous substrate metal layer reflects the light radiation emitted by the plurality of wires; and
forming at least one electrically conducting contact area on at least one of the wires.
16. The method for making a light-emitting microelectronic device according to claim 15 , further comprising, after the growing is completed, forming an insulating layer that encapsulates the wires.