P
USRE49869EActiveUtilityPatentIndex 58

Group-III nitride devices and systems on IBAD-textured substrates

Assignee: IBEAM MAT INCPriority: Feb 10, 2015Filed: Mar 26, 2021Granted: Mar 12, 2024
Est. expiryFeb 10, 2035(~8.6 yrs left)· nominal 20-yr term from priority
Inventors:MATIAS VLADIMIRYUNG CHRISTOPHER
H10P 14/3416H10P 14/3258H10P 14/3251H10P 14/3238H10P 14/3216H10P 14/2923H10P 14/24H10P 14/36H10P 14/3241H10P 14/2922H10P 14/2925H10H 20/856H10H 20/815H10H 20/8583H10H 20/01335H10H 20/818H10F 99/00H10F 77/16H10F 71/1278H10F 77/1698H10H 20/825H10H 20/814H01L 33/32H01L 21/02425H01L 21/02458H01L 21/02488H01L 21/02505H01L 21/02516H01L 21/0254H01L 21/0262H01L 31/00H01L 31/036H01L 33/007H01L 33/18H01L 33/644H01L 33/12H01L 33/60
58
PatentIndex Score
0
Cited by
108
References
43
Claims

Abstract

A multilayer structure including a hexagonal epitaxial layer, such as GaN or other group III-nitride (III-N) semiconductors, a <111>oriented textured layer, and a non-single crystal substrate, and methods for making the same. The textured layer has a crystalline alignment preferably formed by the ion-beam assisted deposition (IBAD) texturing process and can be biaxially aligned. The in-plane crystalline texture of the textured layer is sufficiently low to allow growth of high quality hexagonal material, but can still be significantly greater than the required in-plane crystalline texture of the hexagonal material. The IBAD process enables low-cost, large-area, flexible metal foil substrates to be used as potential alternatives to single-crystal sapphire and silicon for manufacture of electronic devices, enabling scaled-up roll-to-roll, sheet-to-sheet, or similar fabrication processes to be used. The user is able to choose a substrate for its mechanical and thermal properties, such as how well its coefficient of thermal expansion matches that of the hexagonal epitaxial layer, while choosing a textured layer that more closely lattice matches that layer. Electronic devices such as LEDs can be manufactured from such structures. Because the substrate can act as both a reflector and a heat sink, transfer to other substrates, and use of external reflectors and heat sinks, is not required, greatly reducing costs. Large area devices such as light emitting strips or sheets may be fabricated using this technology.

Claims

exact text as granted — not AI-modified
What is claimed is: 
     
       1. An electronic or optoelectronic device comprising a substrate on which an active region of the device was grown, said substrate acting as a reflector, the device further comprising an epitaxial hexagonal crystal layer and a layer of a cubic material having a <111> out of plane orientation and having an in-plane crystalline texture with a full width half maximum (FWHM) less than or equal to approximately  15 ; 12°. 
 wherein the layer of cubic material has an in-plane crystalline texture having a FWHM of less than or equal to approximately 12°. 
 
     
     
       2. The device of  claim 1  selected from the group consisting of LED, MOSFET, MESFET, HEMT, Heterojunction FET, heterojunction bipolar transistor (HBT), thin-film transistor, sensor, memristor, laser diode (LD), SAW device, spintronic device, photodetector, and photovoltaic (PV) diode. 
     
     
       3. The device of  claim 1  wherein said substrate is a heat sink. 
     
     
       4. The device of  claim 3  wherein said substrate has a thermal conductivity greater than approximately 25 W/m·K. 
     
     
       5. The device of  claim 4  wherein said substrate has a thermal conductivity greater than approximately 50 W/m·K. 
     
     
       6. The device of  claim 1  wherein said substrate comprises a metal or alloy. 
     
     
       7. The device of  claim 1  wherein said substrate is flexible. 
     
     
       8. The device of  claim 1  wherein said substrate is not a single crystal. 
     
     
       9. The device of  claim 1  comprising a light emitting region which is two-dimensional and not one or more point sources. 
     
     
       10. The device of  claim 9  in the form of a sheet or strip. 
     
     
       11. The device of  claim 1  comprising an LED on a metal substrate, wherein an operating temperature of the LED is less than approximately two thirds that of an LED on sapphire. 
     
     
       12. The device of  claim 11  wherein an operating temperature of the LED is less than approximately one half that of an LED on sapphire. 
     
     
       13. The device of  claim 1  that is cool to touch during operation. 
     
     
       14. The device of  claim 1  integrated into an electronic system. 
     
     
       15. The device of  claim 14  wherein said electronic system is selected from the group consisting of an LED-based luminaire, a light emitting strip, a light emitting sheet, an optical display, and a MicroLED display. 
     
     
       16. The device of  claim 1  wherein the epitaxial hexagonal crystal layer comprises a group III-nitride semiconductor. 
     
     
       17. The device of  claim 16  wherein the epitaxial hexagonal crystal layer comprises GaN. 
     
     
       18. The device of  claim 1  wherein the layer of cubic material has been textured by ion beam-assisted deposition (IBAD). 
     
     
       19. The device of  claim 1  wherein the layer of cubic material is selected from the group consisting of MgO, CeO 2 , a bixbyite structure, Sc 2 O 3 , Y 2 O 3 , Al 2 O 3 , a fluorite structure, TiN, a rock salt structure, CaF 2 , cubic ZrO 2 , HfO 2 , ScO x , and Mn 2 O 3 . 
     
     
       20. The device of  claim 1  wherein the epitaxial hexagonal crystal layer comprises GaN and the substrate comprises molybdenum, tungsten, tantalum, alloys thereof, Mo—Cu, or TZM. 
     
     
       21. The device of  claim 1  comprising a base layer disposed between the substrate and the layer of cubic material. 
     
     
       22. The device of  claim 21  wherein the base layer comprises amorphous Al 2 O 3 , Y 2 O 3 , or SiO 2 . 
     
     
       23. The device of  claim 1  comprising one or more epitaxial buffer layers disposed between the layer of cubic material and the epitaxial hexagonal crystal layer. 
     
     
       24. The device of  claim 23  wherein the epitaxial buffer layers each have a lattice parameter that successively provides a transition from the lattice parameter of the cubic material to the lattice parameter of the epitaxial hexagonal crystal layer. 
     
     
       25. The device of  claim 24  wherein the epitaxial hexagonal crystal layer comprises GaN and the epitaxial buffer layers comprise a layer of Sc 2 O 3 , a layer of Zr, and a layer of AlN. 
     
     
       26. An electronic or optoelectronic device comprising a flexible substrate on which an active region of the device was grown epitaxially, said flexible substrate acting as a reflector;
 wherein said flexible substrate is a heat sink. 
 
     
     
       27. The device of  claim 26  selected from the group consisting of LED, MOSFET, MESFET, HEMT, Heterojunction FET, heterojunction bipolar transistor (HBT), thin-film transistor, sensor, memristor, laser diode (LD), SAW device, spintronic device, photodetector, and photovoltaic (PV) diode. 
     
     
       28. The device of  claim 26  wherein said flexible substrate has a thermal conductivity greater than approximately 25 W/m·K. 
     
     
       29. The device of  claim 28  wherein said flexible substrate has a thermal conductivity greater than approximately 50 W/m·K. 
     
     
       30. The device of  claim 26  wherein said flexible substrate comprises a metal or alloy. 
     
     
       31. The device of  claim 26  wherein said substrate is flexible. 
     
     
       32. The device of  claim 26  wherein said flexible substrate is not a single crystal. 
     
     
       33. The device of  claim 26  integrated into an electronic system. 
     
     
       34. The device of  claim 33  wherein said electronic system is selected from the group consisting of an LED-based luminaire, a light emitting strip, a light emitting sheet, an optical display, and a MicroLED display. 
     
     
       35. An electronic or optoelectronic device comprising a flexible substrate on which an active region of the device was grown epitaxially, said flexible substrate acting as a reflector;
 wherein the device comprises a light emitting region which is two-dimensional and not one or more point sources. 
 
     
     
       36. The device of  claim 35  selected from the group consisting of LED, MOSFET, MESFET, HEMT, Heterojunction FET, heterojunction bipolar transistor (HBT), thin-film transistor, sensor, memristor, laser diode (LD), SAW device, spintronic device, photodetector, and photovoltaic (PV) diode. 
     
     
       37. The device of  claim 35  wherein said flexible substrate comprises a metal or alloy. 
     
     
       38. The device of  claim 35  wherein said substrate is flexible. 
     
     
       39. The device of  claim 35  wherein said flexible substrate is not a single crystal. 
     
     
       40. The device of  claim 35  in the form of a sheet or strip. 
     
     
       41. The device of  claim 35  integrated into an electronic system. 
     
     
       42. The device of  claim 41  wherein said electronic system is selected from the group consisting of an LED-based luminaire, a light emitting strip, a light emitting sheet, an optical display, and a MicroLED display. 
     
     
       43. The device of claim 1 wherein a FWHM of an in-plane crystalline texture of the epitaxial hexagonal crystal layer is less than 1°.

Cited by (0)

No later patents cite this yet.

References (0)

No backward citations on record.