Research-grade epitaxial wafers

Optimized Process Integration with Epitaxial Structures

Zn diffusion is a thermal doping method where zinc atoms are diffused into the top surface of the epitaxial layer to create a p-type region. By carefully engineering the diffusion depth and profile, EpiSolution achieves low-leakage p-n junctions with precise control of carrier concentration.

Our Zn diffusion process is fully compatible with MOCVD-grown PIN and APD structures and is supported by a suite of advanced processing techniques:

• PECVD SiO₂ Passivation: Prevents lateral diffusion and stabilizes the wafer surface
• Lift-Off Patterned Metal Masks: Define localized diffusion areas for selective doping
• RIE Etching Integration: Enables precise pre- and post-diffusion patterning
• Automated Thermal Profile Control: Ensures consistent diffusion depth and concentration

Performance Highlights

• Controlled Diffusion Depth: Tunable from 0.5 µm to 3 µm
• Low Junction Resistance and Excellent Thermal Stability
• Uniform Dopant Distribution:Doping concentration variation < ±5%
• Low Leakage Current: < 1 nA in optimized PIN and APD structures
• Fully Compatible with InP-Based Epitaxial Stacks:

Target Applications

• InGaAs PIN Photodiodes
• InGaAs Avalanche Photodiodes (APDs)
• Quantum Cascade Lasers (QCLs) – P-contact formation
• High-speed and high-sensitivity optoelectronic devices