Integration of LED driver circuit with LED
Various embodiments provide materials and methods for integrating exemplary heterostructure field-effect transistor (HFET) driver circuit or thyristor driver circuit with LED structures to reduce or eliminate resistance and/or inductance associated with their conventional connections.
1. An integrated light emitting diode (LED) device comprising:
a heterostructure field-effect transistor (HFET) driver circuit comprising an epi-layer disposed over a substrate, wherein the epi-layer comprises a first portion comprising a first dopant profile and configured to form a heterostructure and a second portion comprising a second dopant profile; and
an LED structure disposed over the second portion of the epi-layer and as an extended drain region of the HFET driver circuit, wherein the LED structure comprises a multi-quantum-well (MQW) active region.
2. The device of claim 1 , wherein the HFET driver circuit has a gate length ranging from about 0.1 μm to about 10 μm.
3. The device of claim 1 , wherein the LED structure has a width ranging from about 100 μm to 1,000 μm.
4. The device of claim 1 , wherein the substrate comprises one or more of GaN, SiC, Al 2 O 3 , Si, Si on insulator, or combinations thereof.
5. The device of claim 1 , wherein each of the HFET driver circuit and the LED structure comprises one or more materials selected from the group consisting of GaN, AlN, InN, InGaN, AlInGaN, AlGaN, InP, and combinations thereof.
6. The device of claim 1 , wherein the heterostructure of the HFET driver circuit comprises:
a cap layer over the first portion of the epi-layer; and
a 2-dimensional electron gas layer at an interface between the cap layer and the first portion of the epi-layer.
7. The device of claim 6 , wherein the cap layer has an AlN molar fraction ranging from about 5% to about 40%.
8. The device of claim 6 , wherein the cap layer has a thickness ranging from about 20 nm to about 1000 nm.
9. The device of claim 1 , wherein the second portion of the epi-layer is n-doped, and wherein the LED structure further comprises:
an n-doped layer epitaxially disposed over the n-doped second portion of the epi-layer,
the MQW active region epitaxially disposed over the n-doped layer, and
one or more p-doped layers epitaxially disposed over the MQW active region.
10. The device of claim 1 , wherein the HFET driver circuit further comprises a drain contact disposed over the second portion of the epi-layer, and the LED structure further comprises an n-contact for the MQW active region, wherein the n-contact of the LED structure is bonded with and disposed over the drain contact of the HFET driver circuit.
11. The device of claim 10 , wherein the n-contact of the LED structure is a thinned conducting substrate having a thickness ranging from about 1 μm to about 100 μm.