Glass substrate for high-frequency device and circuit board for high-frequency device

Patent metadata

Field	Value
Publication number	US-11708294-B2
Application number	US-201916720979-A
Country	US
Kind code	B2
Filing date	Dec 19, 2019
Priority date	Sep 13, 2016
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

A glass substrate for a high-frequency device, which contains SiO 2 as a main component, the glass substrate having a total content of alkali metal oxides in the range of 0.001-5% in terms of mole percent on the basis of oxides, the alkali metal oxides having a molar ratio represented by Na 2 O/(Na 2 O+K 2 O) in the range of 0.01-0.99, and the glass substrate having a total content of alkaline earth metal oxides in the range of 0.1-13% in terms of mole percent on the basis of oxides, wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

First claim

The invention claimed is:

1. A glass substrate for a high-frequency device, which comprises, in terms of mole percent on the basis of oxides:
SiO 2 in the range of 60% or more;
CaO in the range of 0-1%,
alkali metal oxides in total in the range of 0.001-5%, a molar ratio represented by Na 2 O/(Na 2 O+K 2 O) being in the range of 0.75-0.98;
Al 2 O 3 and B 2 O 3 in total in the range of 25-40%, a molar ratio represented by Al 2 O 3 /(Al 2 O 3 ±B 2 O 3 ) being in the range of 0-0.45; and
alkaline earth metal oxides in total in the range of 0.1-13%,
wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

2. The glass substrate for a high-frequency device according to claim 1 , which has a content of B 2 O 3 in the range of 9-30% and a content of Al 2 O 3 in the range of 0-10%, in terms of mole percent on the basis of oxides.

3. The glass substrate for a high-frequency device according to claim 1 , which has a content of Fe, in terms of Fe 2 O 3 , of 0.012% or less in terms of mole percent on the basis of oxides.

4. The glass substrate for a high-frequency device according to claim 1 , which has the content of SiO 2 in the range of 60-75%, a content of MgO in the range of 0-13%, a content of SrO in the range of 0-13, and a content of BaO in the range of 0-10%, in terms of mole percent on the basis of oxides, and has the dielectric dissipation factor at 35 GHz of 0.003 or less.

5. The glass substrate for a high-frequency device according to claim 1 , which is amorphous.

6. The glass substrate for a high-frequency device according to claim 1 , which has a β-OH value in the range of 0.05-0.6 mm −1 .

7. The glass substrate for a high-frequency device according to claim 1 , which has a relative permittivity at 35 GHz of 10 or less.

8. The glass substrate for a high-frequency device according to claim 1 , which has an average thermal expansion coefficient over the range of from 50° C. to 350° C. in the range of 3-15 ppm/° C.

9. The glass substrate for a high-frequency device according to claim 1 , which has a Young's modulus of 40 GPa or higher.

10. The glass substrate for a high-frequency device according to claim 1 , which has a porosity of 0.1% or less.

11. The glass substrate for a high-frequency device according to claim 1 , which has a transmittance at 350-nm wavelength of 50% or higher.

12. The glass substrate for a high-frequency device according to claim 1 , which has a thickness in the range of 0.05-1 mm and a substrate area in the range of 225-10,000 cm 2 .

13. A circuit board for a high-frequency device, comprising:
the glass substrate according to claim 1 ; and
a wiring layer formed on the main surface of the glass substrate,
wherein the circuit board has a transmission loss at 35 GHz of 1 dB/cm or less.

Assignees

• Agc Inc

Inventors

• Ono Kazutaka
• Nomura Shuhei
• Kidera Nobutaka
• Takeshita Nobuhiko

Classifications

• C03B17/064

  by the overflow downdraw fusion process; Isopipes therefor · CPC title

• C03B17/02

  Forming {molten} glass coated with coloured layers; {Forming molten glass of different compositions or layers; Forming molten glass comprising reinforcements or inserts} · CPC title

• C03B19/14 Primary

  by gas- {or vapour-} phase reaction processes · CPC title

• C03B25/08

  of glass sheets · CPC title

• C03C3/089 Primary

  containing boron · CPC title