ALUMINA SINTERED BODY AND BASE SUBSTRATE FOR OPTICAL DEVICE

• US 20180230020A1
• Filed: 03/01/2018
• Published: 08/16/2018
• Est. Priority Date: 09/30/2015
• Status: Active Grant

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: MATSUSHIMA, Kiyoshi, Watanabe, Morimichi, Sato, Kei, Nanataki, Tsutomu
• Granted Patent: US 10,427,949 B2
• Time in Patent Office: Days
• CPC Class Codes: C01F 7/02 Aluminium oxide; Aluminium hydroxide; Aluminates
• CPC Class Codes: C01P 2002/60 Compounds characterised by their crystallite size
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2002/80 defined by measured data other than those specified in group C01P2002/70
• CPC Class Codes: C01P 2004/02 obtained by optical microscopy
• CPC Class Codes: C01P 2006/16 Pore diameter
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/5292 Flakes, platelets or plates
• CPC Class Codes: C04B 2235/5296 with a defined aspect ratio, e.g. indicating sphericity
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/5445 submicron sized, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2235/5472 Bimodal, multi-modal or multi-fraction
• CPC Class Codes: C04B 2235/6025 Tape casting, e.g. with a doctor blade
• CPC Class Codes: C04B 2235/6567 Treatment time
• CPC Class Codes: C04B 2235/6586 Processes characterised by the flow of gas
• CPC Class Codes: C04B 2235/72 Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
• CPC Class Codes: C04B 2235/724 Halogenide content
• CPC Class Codes: C04B 2235/786 Micrometer sized grains, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/787 Oriented grains
• CPC Class Codes: C04B 35/115 Translucent or transparent products
• CPC Class Codes: C04B 35/632 : Organic additives
• CPC Class Codes: C04B 35/6342 : Polyvinylacetals, e.g. polyvinylbutyral [PVB]
• CPC Class Codes: C04B 35/638 : Removal thereof
• CPC Class Codes: C04B 35/645 : Pressure sintering
• CPC Class Codes: G02B 1/02 : made of crystals, e.g. rock-salt, semi-conductors G02B1/08 takes precedence
• CPC Class Codes: H01L 33/007 : comprising nitride compounds
• CPC Class Codes: H01L 33/0087 : with a substrate not being a II-VI compound

Abstract

An alumina sintered body of the present invention has a degree of c-plane orientation of 5% or more, which is determined by a Lotgering method using an X-ray diffraction profile in a range of 2θ=20° to 70° obtained under X-ray irradiation, and an XRC half width of 15.0° or less in rocking curve measurement, an F content of less than 0.99 mass ppm when measured by D-SIMS, a crystal grain diameter of 15 to 200 μm, and 25 or less pores having a diameter of 0.2 μm to 1.0 μm when a photograph of a viewing area 370.0 μm in a vertical direction and 372.0 μm in a horizontal direction taken at a magnification factor of 1000 is visually observed.

Claims

1. An alumina sintered body having:

a degree of c-plane orientation of 5% or more, which is determined by a Lotgering method using an X-ray diffraction profile in a range of 2θ

=20°

to 70°

obtained under X-ray irradiation, and an XRC half width of 15.0°

or less in rocking curve measurement;

an F content of less than 0.99 mass ppm when measured by D-SIMS;

a crystal grain diameter of 15 to 200 μ

m; and

25 or less pores having a diameter of 0.2 μ

m to 1.0 μ

m when a photograph of a viewing area 370.0 μ

m in a vertical direction and 372.0 μ

m in a horizontal direction taken at a magnification factor of 1000 is visually observed.

2. The alumina sintered body according to claim 1,

wherein, the F content is 0.1 mass ppm or less.

3. The alumina sintered body according to claim 1,

wherein, the crystal grain diameter is 20 to 200 μ

m.

4. The alumina sintered body according to claim 1,

wherein, the number of the pores is 15 or less.

5. The alumina sintered body according to claim 1,

wherein, the F content is 0.1 mass ppm or less,

the crystal grain diameter is 20 to 200 μ

m, and

the number of the pores is 10 or less.

6. The alumina sintered body according to claim 5,

wherein, the degree of c-plane orientation is 60% or more, and the XRC half width is 5.0°

or less,

the crystal grain diameter is 40 to 95 μ

m, and

the number of the pores is 7 or less.

7. The alumina sintered body according to claim 6,

wherein, the crystal grain diameter is 45 to 95 μ

m, and

the number of the pores is 5 or less.

8. The alumina sintered body according to claim 7,

wherein, the degree of c-plane orientation is 96% or more, and the XRC half width is 2.6°

or less, and

the number of the pores is 3 or less.

9. The alumina sintered body according to claim 1,

wherein, the alumina sintered body having a thickness of 0.5 mm has an in-line transmittance of 78% or more at 300 to 1000 nm.

10. A base substrate for optical device, comprising the alumina sintered body according to claim 1.