Segmented LED with embedded transistors
A device may include a substrate having a first embedded transistor in a first region and a second embedded transistor in a second region. The first region and the second region may be separated by trench extending through at least a portion of an epitaxial layer formed on the substrate. The first embedded transistor may be connected to a first light emitting diode (LED) and the second embedded transistor may be connected to a second LED. A first optical isolation layer may be between the epitaxial layer and the first region of the substrate. A second optical isolation layer may be between the epitaxial layer and the second region of the substrate.
1. A device comprising:
a substrate;
one or more epitaxial layers on the substrate;
a first transistor embedded in a first region of the substrate; and
a second transistor embedded in a second region of the substrate, the first region and the second region separated by a trench extending entirely through the substrate and through one or more portions of the one or more epitaxial layers.
2. The device of claim 1 , wherein the first embedded transistor is coupled to a first light emitting diode (LED) formed by corresponding portions of the one or more epitaxial layers on the first region of the substrate, and the second embedded transistor is coupled to a second LED formed by corresponding portions of the one or more epitaxial layers on the second region of the substrate.
3. The device of claim 1 , further comprising:
a first optical isolation layer between the one or more epitaxial layers and the first region of the substrate; and
a second optical isolation layer between the one or more epitaxial layers and the second region of the substrate.
4. The device of claim 1 , wherein the one or more epitaxial layers include:
a first semiconductor layer;
a second semiconductor layer, with the first semiconductor layer between the substrate and the second semiconductor layer; and
an active region between the first and second semiconductor layers.
5. The device of claim 4 , wherein the trench extends through at least a portion of the first semiconductor layer.
6. The device of claim 4 , wherein the trench extends through an entire thickness of the first semiconductor layer, an entire thickness of the active region, and at least a portion of the second semiconductor layer.
7. The device of claim 1 , further comprising a common contact layer, with the one or more epitaxial layers between the substrate and the common contact layer.
8. The device of claim 7 , wherein the trench extends through an entire thickness of the one or more epitaxial layers and an entire thickness of the common contact layer.
9. The device of claim 8 , further comprising:
a contact in the trench; and
a passivation layer between the contact and the substrate and one or more portions of the one or more epitaxial layers.
10. The device of claim 7 , further comprising a wavelength converting layer, with the common contact layer between the one or more epitaxial layers and the wavelength converting layer.
11. An LED array, comprising:
a substrate;
a first transistor embedded in a first region of the substrate;
a second transistor embedded in a second region of the substrate, the first and second regions of the substrate being separated by a trench extending entirely through the substrate and through at least a portion of a first semiconductor layer on the substrate;
a first LED positioned on the first region of the substrate, coupled to the first embedded transistor, and including a portion of the first semiconductor layer; and
a second LED positioned on the second region of the substrate, coupled to the second embedded transistor, and including a portion of the first semiconductor layer.
12. The LED array of claim 11 , wherein (i) the first and second LEDs are less than about 100 μm wide, or (ii) the trench is less than about 20 μm wide.
13. The LED array of claim 11 , further comprising:
a first optical isolation layer between the first semiconductor layer and the first region of the substrate; and
a second optical isolation layer between the first semiconductor layer and the second region of the substrate.
14. The LED array of claim 13 , wherein each one of the first and second LEDs includes:
a corresponding region of the first semiconductor layer;
a corresponding region of a second semiconductor layer, with the first semiconductor layer between the substrate and the second semiconductor layer; and
a corresponding active region between the corresponding regions of the first and second semiconductor layers.
15. The LED array of claim 14 , wherein the trench extends through an entire thickness of the first semiconductor layer, an entire thickness of the active region, and a portion of the second semiconductor layer.
16. The LED array of claim 12 , further comprising a common contact layer, with the first LED and the second LED between the substrate and the common contact layer.
17. The device of claim 2 , wherein (i) the first and second LEDs are less than about 100 μm wide, or (ii) the trench is less than about 20 μm wide.