High-voltage solid-state transducers and associated systems and methods
High-voltage solid-state transducer (SST) devices and associated systems and methods are disclosed herein. An SST device in accordance with a particular embodiment of the present technology includes a carrier substrate, a first terminal, a second terminal and a plurality of SST dies connected in series between the first and second terminals. The individual SST dies can include a transducer structure having a p-n junction, a first contact and a second contact. The transducer structure forms a boundary between a first region and a second region with the carrier substrate being in the first region. The first and second terminals can be configured to receive an output voltage and each SST die can have a forward junction voltage less than the output voltage.
1. A solid-state transducer (SST) system, comprising:
a carrier substrate;
a plurality of SST dies on the carrier substrate, wherein individual SST dies include a transducer structure having a p-n junction, a first contact, and a second contact, the transducer structure forming a boundary between a first region and a second region, wherein the first contact is at a backside of the transducer structure in the first region, wherein the second contact extends along at least a portion of a backside of the first contact and includes a buried contact that extends through a plane containing the first contact and comprises—
a via having a sidewall extending from the first region, completely through the first contact, to beyond the p-n junction,
a dielectric material along the backside of the first contact and along the sidewall of the via, wherein the dielectric material does not cover a portion of the transducer structure beyond the p-n junction, and
a conductive material extending into the via on the dielectric material and onto the portion of the transducer structure not covered by the dielectric material, wherein the dielectric material is positioned between the conductive material and the p-n junction to electrically isolate the buried contact from the p-n junction; and
at least one interconnect region in the first region between two adjacent SST dies, wherein—
a portion of the second contact of one of the plurality of SST dies extends beyond the backside of the first contact and beyond the transducer structure into the interconnect region,
the portion of the second contact electrically couples to the first contact of an adjacent SST die to electrically couple the adjacent SST dies together in series at the interconnect region, and
an opening is positioned between the transducer structures of the two adjacent SST dies to expose the portion of the second contact that extends beyond the backside of the of the first contact of one of the plurality of SST dies and a portion of the first contact of the adjacent SST die that extends beyond the backside such that the first and second contacts of the adjacent SST dies are coupled together in the opening.
2. The SST system of claim 1 wherein:
the transducer structure of the individual SST dies comprise a P-type gallium nitride (P-type GaN) facing toward the first region, an N-type gallium nitride (N-type GaN) facing toward the second region, and an indium gallium nitride (InGaN) between the P-type GaN and the N-type GaN;
the first contact is electrically coupled to the P-type GaN; and
the second contact is electrically coupled to the N-type GaN.
3. The SST system of claim 1 wherein the first contact comprises a reflective material.
4. The SST system of claim 1 , further comprising:
a first terminal electrically coupled to the first contact of a first of the plurality of SST dies; and
a second terminal electrically coupled to the second contact of a second of the plurality of SST dies, wherein the first SST die is the first SST die coupled in series and the second SST die is the last SST die coupled in series.
5. The SST system of claim 4 wherein the first and second terminals are electrically accessible from the first region.
6. The SST system of claim 1 wherein the transducer structure is configured to emit electromagnetic radiation in at least one of the ultraviolet spectrum, the visible spectrum, and the infrared spectrum.
7. The SST system of claim 1 wherein the carrier substrate is made from a non-conductive material.
8. A solid-state transducer (SST) device, comprising:
a first terminal;
a second terminal, wherein the first and second terminals are positioned to couple to a power supply;
a plurality of SST dies electrically connected in series between the first and second terminals, wherein the plurality of SST dies includes a first SST die adjacent to a second SST die, wherein the individual SST dies comprise—
a transducer structure having a p-n junction, the transducer structure forming a boundary between a first region and a second region;
a first contact in the first region and electrically connected to the p-n junction; and
a second contact electrically connected to the p-n junction, wherein the second contact extends along at least a portion of a backside of the first contact and includes a buried contact projecting through the first contact into the transducer structure beyond the p-n junction, and wherein the second contact is electrically isolated from the first contact by a dielectric material between the first contact and the second contact; and
an interconnect region between the first and second SST dies, wherein a portion of the second contact of first SST die extends beyond the backside of the first contact and beyond the transducer structure of the first SST die into the interconnect region, and wherein the portion of the second contact of the first SST die electrically couples to the first contact of the adjacent second SST die such that the first and second SST dies are electrically coupled together in series at the interconnect region,
wherein the transducer structure of the first SST die and the transducer structure of the second SST die define an opening at the interconnect region that exposes the portion of the second contact that extends beyond the backside of the of the first contact of the first SST die and a portion of the first contact of the second SST die that extends beyond the backside of the second SST die such that the second contact of the first SST die is coupled to the first contact of the second SST die in the opening.
9. The SST device of claim 8 wherein:
the transducer structure comprises a P-type gallium nitride (P-type GaN) facing toward the first region, an N-type gallium nitride (N-type GaN) facing toward the second region, and an indium gallium nitride (InGaN) between the P-type GaN and the N-type GaN;
the first contact is electrically coupled to the P-type GaN;
the second contact is electrically coupled to the N-type GaN, wherein the second contact extends through a plane containing the first contact to the N-type GaN; and
the first and second terminals are electrically accessible from the first region.
10. The SST device of claim 8 wherein the first and second terminals are electrically accessible from a surface facing away from the carrier substrate.
11. A solid-state transducer (SST) device, comprising:
a first terminal;
a second terminal;
a plurality of SST dies electrically connected in series between the first and second terminals, wherein the plurality of SST dies includes a first SST die adjacent to a second SST die, and wherein the individual SST dies comprise—
a transducer structure having a p-n junction, the transducer structure forming a boundary between a first region and a second region;
a first contact in the first region and electrically connected to the p-n junction; and
a second contact electrically connected to the p-n junction, wherein the second contact extends along at least a portion of a backside of the first contact and includes a buried contact projecting through the first contact into the transducer structure beyond the p-n junction, and wherein the second contact is electrically isolated from the first contact by a dielectric material between the first contact and the second contact;
an interconnect region between the first and second SST dies, wherein a portion of the second contact of first SST die extends beyond the backside of the first contact and beyond the transducer structure of the first SST die into the interconnect region, and wherein the portion of the second contact of the first SST die electrically couples to the first contact of the adjacent second SST die such that the first and second SST dies are electrically coupled together in series at the interconnect region; and
an isolating protrusion of dielectric material in the interconnect region between the second contacts of the adjacent first and second SST dies, wherein the isolating protrusion defines a lateral bound of the first SST die from a lateral bound of the adjacent second SST die.
12. The SST device of claim 11 wherein:
the transducer structure includes a P-type GaN facing toward the first region, an N-type GaN facing toward the second region, and InGaN between the P-type GaN and the N-type GaN;
the first contact is electrically coupled to the P-type GaN;
the second contact is electrically coupled to the N-type GaN; and
the first and second terminals are electrically accessible from the first region.
13. The SST device of claim 11 wherein:
the transducer structure includes a P-type GaN facing toward the first region, an N-type GaN facing toward the second region, and InGaN between the P-type GaN and the N-type GaN;
the first contact is electrically coupled to the P-type GaN;
the second contact is electrically coupled to the N-type GaN; and
the first terminal is electrically accessible from the second region.