Thermal control for formation and processing of aluminum nitride

Patent metadata

Field	Value
Publication number	US-2021108336-A1
Application number	US-202017082611-A
Country	US
Kind code	A1
Filing date	Oct 28, 2020
Priority date	Nov 10, 2017
Publication date	Apr 15, 2021
Grant date	—

Abstract

In various embodiments, controlled heating and/or cooling conditions are utilized during the fabrication of aluminum nitride single crystals and aluminum nitride bulk polycrystalline ceramics. Thermal treatments may also be utilized to control properties of aluminum nitride crystals after fabrication.

First claim

What is claimed is:

1 .- 73 . (canceled)

74 . A single-crystal AlN substrate having (i) a diameter of at least approximately 30 mm and (ii) an ultraviolet (UV) transparency metric ranging from approximately 5 cm 3 to approximately 5000 cm 3 at a wavelength of interest of 265 nm, the UV transparency metric being defined in cm 3 as:

d

10
×
FWHM
×

α
2

wherein d is a diameter of the AlN substrate in mm, FWHM is a full-width at half-maximum of an x-ray diffraction curve of the AlN substrate in radians, and α is an absorption coefficient of the AlN substrate at the wavelength of interest.

75 . The AlN substrate of claim 74 , wherein the diameter of the AlN substrate is at least approximately 50 mm.

76 . The AlN substrate of claim 74 , wherein a diameter of the AlN substrate is no greater than approximately 150 mm.

77 . The AlN substrate of claim 74 , wherein a thermal conductivity of the AlN substrate is approximately 290 W/m·K or greater at room temperature.

78 . The AlN substrate of claim 74 , wherein a crystalline orientation of the AlN substrate is substantially parallel to a c-axis.

79 . The AlN substrate of claim 74 , wherein a crystalline orientation of the AlN substrate is angled at least approximately 10° relative to a c-axis.

80 . The AlN substrate of claim 74 , further comprising a light-emitting device disposed thereover.

81 . The AlN substrate of claim 80 , wherein the light-emitting device is configured to emit ultraviolet light.

82 . The AlN substrate of claim 80 , wherein the light-emitting device comprises a light-emitting diode or a laser.

83 . The AlN substrate of claim 74 , wherein a density of threading edge dislocations in the AlN substrate is less than 5×10 3 cm −3 .

84 . The AlN substrate of claim 74 , wherein a density of threading screw dislocations in the AlN substrate is less than 10 cm −3 .

85 . The AlN substrate of claim 74 , wherein a silicon concentration of the AlN substrate is less than 1×10 17 cm −3 .

86 . The AlN substrate of claim 74 , wherein an oxygen concentration of the AlN substrate is less than 1×10′ cm −3 .

87 . The AlN substrate of claim 74 , wherein a carbon concentration of the AlN substrate is less than 3×10 17 cm −3 .

88 . The AlN substrate of claim 74 , wherein a ratio of the carbon concentration of the AlN substrate to the oxygen concentration of the AlN substrate is less than 0.5.

89 . The AlN substrate of claim 74 , wherein a thickness of the substrate is 100 μm or greater.

90 . The AlN substrate of claim 74 , wherein a thickness of the substrate is 200 μm or greater.

91 . The AlN substrate of claim 74 , wherein a thickness of the substrate is 2 mm or greater.

92 . The AlN substrate of claim 74 , further comprising an epitaxial semiconductor layer disposed thereover.

Assignees

• Bondokov Robert T
• Chen Jianfeng
• Yamaoka Keisuke
• Wang Shichao
• Rao Shailaja P
• Suzuki Takashi
• Schowalter Leo J

Inventors

• Bondokov Robert T
• Chen Jianfeng
• Yamaoka Keisuke
• Wang Shichao
• Rao Shailaja P
• Suzuki Takashi
• Schowalter Leo J

Classifications

• H10P14/2908

  Nitrides · CPC title

• H10H20/0137 Primary

  the light-emitting regions comprising nitride materials · CPC title

• C01B21/072

  with aluminium · CPC title

• C30B23/002

  Controlling or regulating · CPC title

• H01S5/0217

  Removal of the substrate · CPC title