News Release
June 5, 2024
Nippon Electric Glass Co., Ltd.

Development of GC Core™ - Glass-Ceramics Core
Substrate for Next-Generation Semiconductor Packages- High-speed, crack-free and economical micro through-hole (via) processing -Nippon Electric Glass Co., Ltd. (Head Office: Otsu, Shiga, Japan; President: Akira Kishimoto;“NEG”) has developed a glass-ceramics core substrate (hereinafter referred to as the “GCCore™”), which has promising potential for use in next-generation semiconductor packages.

GC Core™ developed by NEG. Processed with a Via Mechanics laser processing machine.

■ Development backgroundIn recent years, with the growing demand for data centers and the increase in data traffic dueto the spread of technologies such as generative artificial intelligence, there has been a demandfor higher-performance and lower-power semiconductors used in the infrastructure that supports
these technologies.
To improve the performance of semiconductors, it is essential to miniaturize circuits, develop
chiplets, *1 and increase the size of substrates. However, conventional plastic core substrates *2
make it difficult to miniaturize circuits, and they also have rigidity issues, such as deformation when1

mounting multiple semiconductor chips or making the substrate larger.
For this reason, progress is being made in developing core substrates made of glass, which has
excellent electrical properties, rigidity, and flatness, as a next-generation material to replace plastic
core substrates. The GC Core™ that NEG has recently developed is a core substrate made froma composite of glass powder and ceramic powder. In addition to the properties of a core substrate
made of glass, the new material offers the advantage of being easy to machine when making micro
through-holes.

Where GC Core™ is used

■ Features of GC Core™ developed by Nippon Electric Glass(1) Capable of being drilled with a CO2 laser
Micro through-holes need to be formed in the core substrate to electrically connect the finemetal wiring formed on the front and back sides.
High-speed & crack-free
When drilling holes in ordinary glass substrates with a CO 2 laser, a certain percentage ofthem will develop cracks, which can lead to breakage of the substrate. The GC Core™ has
the properties of ceramics *3 as well, enabling high-speed, crack-free drilling.
Economical and expected to reduce mass production costs
When drilling holes in ordinary glass substrates, the most common method is to use laser
modification and etching to create holes to avoid cracks, but this method is technicallydifficult and requires capital investment. The GC Core™ is economical because the holes
can be made using a widely used CO2 laser machines, and we are expected to reduce mass
production costs.

2

Cross-section of micro through-holes in the newly developed GC Core™ (SEM image)GCC-1 □300 × t 0.4mm, Holes: φ75 µm holes at a Processing rate: over 20,000 holes/min

Processed with a Via Mechanics laser processing machine(2) Low dielectric constant and loss tangent
The glass-ceramic material uses LTCC (low temperature co-fired ceramics), a material
developed exclusively by NEG. This material has a low dielectric constant and loss tangent*4
and reduces signal delay and dielectric loss.
(3) Thin substrates available
The GC Core™ is stronger than glass substrates, allowing for thinner substrates, contributing
to thinner semiconductors. In addition, because it is less likely to break, it offers improvedease of handling during the semiconductor package production process.
(4) Easily change specifications to meet customers’ needs
The properties of the GC Core™ which depend on the composition and compounding ratioof glass and ceramics can be tailored to your needs. In addition to low-dielectric-constanttypes with excellent dielectric properties, we also offer high-expansion types that match thethermal expansion of plastic substrates and high-strength types, making it possible todevelop substrates that can be used for a wide range of applications.

TypeLow dielectric
constant

High CTEHigh mechanicalstrength

Product code

GCC-1

GCC-2

GCC-3

Losstangent

2.45GHz0.00130.00020.000440GHz

0.00160.00040.0007

Dielectricconstant

2.45GHz

3.9

7.0

7.9

40GHz

3.8

6.8

7.6

Thermal expansion
coefficient (ppm/°C)

6.1

8.9

7.4

Bending strength (MPa)1502603403■ Future plans
We have now successfully developed a 300 mm square substrate. We are currently working
on development with the aim of enlarging the substrate to 515 × 510 mm by the end of 2024.
The 300 mm square substrate will be exhibited at the JPCA Show 2024 to be held at Toky o Big
Sight from June 12 to June 14, 2024.
Exhibition Title:

JPCA Show 2024

Period:Wednesday, June 12 to Friday, June 14, 2024

Venue:

Tokyo Big Sight East Exhibition Halls

Booth No.:

6H-01

Exhibition invitation ticket
available free of charge at:https://www.jpcashow.com/show2024/en/*1. Chiplets: An advanced semiconductor packaging technology that densely mounts multiple semiconductor
chips with different functions on a single substrate, improving processing speed.
*2. Core substrate: The substrate material that serves as the base on which semiconductor chips are mounted.
*3. Properties of ceramics: Ceramics have a crystalline structure. The atoms and ions within the crystal arestrongly bonded together. Therefore, ceramics are relatively strong against external forces in terms ofdeformation and cracks.
*4. Loss tangent: A measure of energy when a dielectric substance is polarized. The smaller the loss tangent,
the lower the conversion of electromagnetic energy into heat, and as a result attenuation of signals is reduced.

4

【Company Profile】
Nippon Electric Glass Co., Ltd. is a world-class specialty glass manufacturer headquartered in Otsu
City, Shiga Prefecture. Special glass that creates novel functionality is transformed into a variety ofproducts such as sheets, tubes, threads, and powder, and is used in a wide range of fields, including
semiconductors, displays, automobiles, electronic devices, medical care, and energy. The special
glass developed using the technology and track record that we have honed over our 70-year historyis highly regarded in a wide range of fields, from everyday life to cutting -edge industry.
Company name:

Nippon Electric Glass Co., Ltd.

Representative:Akira Kishimoto, President

Head office location:

7-1 Seiran 2-chome, Otsu, Shiga 520-8639, JapanFounded:December 1, 1949

Business details:

Manufacture and sale of special glass products and fabrication andsale of glass manufacturing machinery

URL:

https://www.neg.co.jp/en(Contact regarding this release)
Nippon Electric Glass Co., Ltd. 7-1 Seiran 2-chome, Otsu, Shiga 520-8639, JapanPR Office, Administrative Division Phone: +81-77-537-1702 (direct)5