966 Vacuum Brazing Furnace: Technical Specifications and Semiconductor Brazing Application

The 966 Vacuum Brazing Furnace is a versatile mid-size unit designed for high-performance brazing, heat treatment, and sintering. Its combination of advanced heating technology, excellent vacuum levels, and uniform temperature control makes it suitable for demanding fields such as aerospace, automotive, medical devices, and semiconductors.

Technical Specifications of the 966 Furnace:

While specifications can vary depending on the manufacturer and customization, a typical 966 Vacuum Brazing Furnace is equipped with the following:

Dimensions: ~600 × 600 × 900 mm.
Maximum Temperature:1300 °C (depending on heating elements used)
Uniformity: ±5 °C across the hot zone (ideal for tight-tolerance brazing)
Vacuum Capability: High vacuum down to 5 × 10⁻⁶ mbar, ensuring oxide-free joints
Heating Elements: Graphite or refractory metal (Mo/W) for clean, efficient heating
Cooling System: High-capacity gas quenching with argon or nitrogen (2–6 bar pressure)
Control System: PLC + SCADA integration with recipe programming and data logging
Loading Method: Front-loading horizontal chamber with water-cooled stainless-steel vessel
Power Supply: 100–150 kW, depending on configuration

These specifications allow the furnace to deliver repeatable brazing cycles and maintain metallurgical cleanliness, essential in semiconductor-grade manufacturing.

The Brazing Process in the 966 Furnace:

To illustrate the brazing sequence, let’s consider an example: brazing copper–molybdenum (Cu–Mo) semiconductor substrates using an active braze alloy.

Step 1: Preparation
The semiconductor substrate (Mo plate) and copper cap or base plate are precision-cleaned to remove surface oxides and contaminants.
A thin preform of Ag–Cu–Ti active braze alloy is placed between the parts. Titanium in the alloy ensures wetting on refractory substrates like Mo or ceramics.

Step 2: Loading the Furnace
Components are carefully positioned on graphite fixtures in the 966 hot zone.
The chamber door is sealed, and the furnace begins evacuation.

Step 3: Pump-Down and Heating
The furnace is evacuated to 10⁻⁵ mbar range, eliminating oxygen and moisture.
The heating cycle is programmed as:
Ramp-up to ~500 °C at moderate speed to remove volatiles.
Hold stage to allow uniform heating.
Brazing temperature raised to ~850–900 °C, depending on alloy composition.

Step 4: Brazing Stage
At brazing temperature, the Ag–Cu–Ti alloy melts and wets both Mo and Cu surfaces.
Capillary action pulls the molten filler into the joint gap, forming a hermetic bond without flux.
Vacuum prevents oxidation, ensuring clean wetting and superior joint strength.

Step 5: Cooling
After brazing soak time, the furnace initiates controlled cooling.
An argon gas quench may be used to accelerate cooling while maintaining joint integrity.
                                                

Outcome and Benefits:

The brazed semiconductor component exhibits high thermal conductivity, hermetic sealing, and excellent mechanical stability. No flux residues or contamination — a major requirement for semiconductor packaging. The VF966 Vacuum Brazing Furnace ensures uniform heating and repeatability, reducing rejection rates.