More Than Lead-Free: How Joinspire Overcame the Pressureless Copper Sintering Challenge to Drive SiC/GaN Upgrades

As silicon carbide (SiC) and gallium nitride (GaN) power devices rapidly advance, choosing the right packaging materials has become a critical engineering challenge:

Traditional high-lead solders are quickly falling behind. Their low thermal conductivity (<50 W/m·K) and modest shear strength (<30 MPa) have become primary bottlenecks restricting power density and long-term device reliability. Worse still, their lead content directly conflicts with increasingly stringent global environmental regulations such as RoHS and REACH.

Facing these constraints, the industry is turning toward sintering copper—an ideal solution that seamlessly balances superior performance with cost-efficiency.

Overcoming the Oxidation Bottleneck

Despite its potential, commercializing sintering copper pastes has historically been plagued by a major technical obstacle: highly active copper powder oxidizes rapidly in ambient air. This oxidation leads to swift performance degradation, severely limiting both shelf storage and operational life.

Joinspire has successfully solved this industry-wide challenge with a core technical breakthrough.

Joinspire’s pressureless sintering copper paste, PL-02U, utilizes an innovative anti-oxidation technology that prevents copper degradation at the molecular level. It demonstrates remarkable storage stability in ambient air at room temperature (25°C). This stability enables long-term warehousing and hassle-free, room-temperature transport—paving the way for the large-scale industrial adoption of sintering copper.

Four Core Competitive Advantages of PL-02U

Beyond its breakthrough anti-oxidation performance, Joinspire PL-02U offers four compelling advantages for power device packaging:

1. Superior Thermal & Mechanical Performance

• Thermal Conductivity (>110 W/m·K): Provides exceptional heat dissipation capability for high-power-density chips.
• Shear Strength (>30 MPa): Delivers robust interconnect reliability suited for high-stress die-attach applications.
• Electromigration Resistance: Ensures stable long-term operational performance under intense electrical fields.
• Dense Sintered Interface: C-SAM (Scanning Acoustic Microscopy) inspection proves a dense, defect-free interface with zero voids or delamination.

2. Strategic Cost Advantage

With precious metal prices remaining persistently high, silver-based materials place a heavy cost burden on manufacturers. PL-02U leverages a cost-effective copper formulation, offering enterprises a reliable, high-value alternative without compromising on performance.

3. Exceptional Processability for High-Yield Production

PL-02U exhibits outstanding rheological stability, making it fully compatible with both high-precision dispensing and stencil/screen printing processes. It supports continuous, stable automated production while effectively preventing defects such as paste bleeding or slump, driving higher production yields.

4. Green and Eco-Friendly Compliance

PL-02U features an environmentally conscious formulation that is completely lead-free and halogen-free, fully complying with international environmental directives including RoHS and REACH.

Conclusion: Empowering Next-Generation Power Electronics

In an era defined by strict environmental standards and soaring performance demands, traditional solders can no longer meet the requirements of next-generation power electronics.

Joinspire’s PL-02U pressureless sintering copper paste delivers a forward-looking material upgrade path for the industry. By uniting green, lead-free compliance with superior thermal and electrical capabilities, Joinspire provides manufacturers with a solid foundation to push SiC and GaN devices to higher levels of power, efficiency, and reliability.