ProductsThermal management products

Nano silver paste for sintering FlowMetal™

A nano silver paste for die-attach bonding which can be bonded at low temperatures

Typical bonding material, like solder melts again when exposed to high operating temperature.

Those power semiconductors (SiC, GaN, etc.) which need to be used at high operating temperature cannot adopt ordinary solder.
Nano silver paste using silver nanoparticles is a new bonding material that solves the above problems.

Although the sintered body of silver nanoparticles is dense, it contains a small number of holes, so it is inferior to the intrinsic value of silver, but shows low electrical resistance, and high thermal conductivity.

Nano silver paste for sintering FlowMetal™

Features

・A bonding material using our unique silver nanoparticles.
We manufacture nano silver paste for bonding materials using silver nanoparticles synthesized by our company.
Higher silver particle concentration (85-97wt%) is possible.
Lead-free.

・Low bonding temperature and excellent heat resistance, electrical conductivity, thermal conductivity.
The low-temperature baking type silver nanoparticle production technology has been applied to enable sinter bonding at low temperatures.
It is known that silver nanoparticles sinter at low temperature due to the size effect, and the melting point of the sintered silver is similar to that of bulk silver (962℃).

・Pressure-free bonding
In spite of pressure-free bonding, the low-temperature sintering process provides high bonding strength through diffusion reactions between the nanoparticles and the substrate metal.
Depending on the bonding conditions, pressure-free bonding may not be suitable. There is also a lineup that enables pressure welding.

Printing Method

Dispensing, metal mask (stencil) printing, and pin transfer are available.

Required surfaces

Gold, Silver, Copper

Product Lineup

SR9200

SR9870

(under development)

SR9950

Features

Lowest sintering

temp.

Pressure-free

Bonding to bare
Cu surface

Low sintering temp.

Middle die size

Applications LED, UV-LED, LD Power semiconductor(Si、SiC) Power semiconductor(Si、SiC)

Small Dies

(~1.5mm×1.5mm)

Large Dies

(~10mm×10mm)

Middle Dies

(~5mm×5mm)

Surface required Ag, Au Ag, Au, Cu Ag, Au

Process

conditions

Printing method

Dispenser

Pin-transfer

Metal mask printing Dispenser

Sintering

atmosphere

Air

Nitrogen

atmosphere or Air

Air

Sintering

temperature (ºC)

150 275 200

Sintering time

(min)

120 30 60
Sintering pressure Pressure-free Pressure-free Pressure-free

Properties

after

sintering

Shear strength

(MPa)

>70

(1mm×1mm)

>90

(2.5mm×2.5mm)

>120

(3mm×3mm)

Thermal

conductivity

(W/mK)

140 300 215

Electric resistivity

(μΩcm)

5 2 3

The values in the table are representative values. Specifications are subject to change without notice.

Applications

Example of printing on a semiconductor die

Bando Chemical's "Thermal Management" special site

Bando Chemical's "Thermal Management"
Contact us Download catalogs & Documents

Contact us