Ceramic substrate

• US 20100136279A1
• Filed: 11/25/2009
• Published: 06/03/2010
• Est. Priority Date: 11/27/2008
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: FURUKAWA, Shigenobu
• Granted Patent: US 8,173,283 B2
• Time in Patent Office: Days
• US Class Current: 428/64.100
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3208 Calcium oxide or oxide-forming salts thereof, e.g. lime
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3418 Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint glass constituents C04B2235/36
• CPC Class Codes: C04B 2235/383 Alpha silicon carbide
• CPC Class Codes: C04B 2235/3878 Alpha silicon nitrides
• CPC Class Codes: C04B 2235/3895 Non-oxides with a defined oxygen content, e.g. SiOC, TiON
• CPC Class Codes: C04B 2235/5409 expressed by specific surface values
• 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 2235/656 characterised by specific heating conditions during heat treatment
• CPC Class Codes: C04B 2235/6567 Treatment time
• CPC Class Codes: C04B 2235/661 Multi-step sintering
• CPC Class Codes: C04B 2235/662 Annealing after sintering
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 2235/94 Products characterised by their shape
• CPC Class Codes: C04B 2235/95 Products characterised by their size, e.g. microceramics
• CPC Class Codes: C04B 2235/96 Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 2235/9638 Tolerance; Dimensional accuracy
• CPC Class Codes: C04B 35/111 : Fine ceramics
• CPC Class Codes: C04B 35/5755 : obtained by gas pressure sintering
• CPC Class Codes: C04B 35/5935 : obtained by gas pressure sintering
• CPC Class Codes: C04B 35/6455 : Hot isostatic pressing
• CPC Class Codes: Y10T 428/21 : Circular sheet or circular blank
• CPC Class Codes: Y10T 428/24479 : including variation in thickness

Abstract

A ceramic substrate according to one aspect of the invention comprises a main surface wherein a diameter of a first imaginary circle inscribed in a circumference of the main surface is represented by C (m), a thickness of the ceramic substrate is represented by h (m), a Poisson ratio of the ceramic substrate is represented by ν, a density of the ceramic substrate is represented by ρ(kg/m³), a Young'"'"'s modulus of the ceramic substrate is represented by E(Pa), a deflection of the ceramic substrate is represented by X (m), the deflection being measured in a condition that the ceramic substrate is supported in a region between the first imaginary circle and a second imaginary circle which is a concentric circle of the first imaginary circle and has a diameter of C-0.01 (m), wherein X≦1.5×(C⁴/h²)×A and A={3×9.807×ρ×(1−ν²)×(5+ν)}/{2⁸×(1+ν)×E} are satisfied.

Claims

1. A ceramic substrate comprising a main surface, wherein a diameter of a first imaginary circle inscribed in a circumference of the main surface is represented by C (m), a thickness of the ceramic substrate is represented by h (m), a Poisson ratio of the ceramic substrate is represented by ν

, a density of the ceramic substrate is represented by ρ

(kg/m³), a Young'"'"'s modulus of the ceramic substrate is represented by E(Pa), a deflection of the ceramic substrate is represented by X (m), the deflection being measured in a condition that the ceramic substrate is supported in a region between the first imaginary circle and a second imaginary circle which is a concentric circle of the first imaginary circle and has a diameter of C-0.01 (m), wherein following equations are satisfied.

X≦

1.5×

(C⁴/h²)×

A

A={3×

9.807×

ρ

×

(1−

ν

²)×

(5+ν

)}/{2⁸×

(1+ν

)×

E}

2. The ceramic substrate according to claim 1, wherein the first imaginary circle has an area of 0.03 m² or more.

3. The ceramic substrate according to claim 1, wherein the thickness h of the ceramic substrate is 0.002 m or less.

4. The ceramic substrate according to claim 1, wherein when the ceramic substrate is freely vibrated in a thickness direction thereof in a condition that the ceramic substrate is supported at an end thereof, a decay time of free vibration of the ceramic substrate is 2 (s) or less.

5. The ceramic substrate according to claim 1, wherein the main surface of the ceramic substrate has a circular shape.