Multiscale Fabrication Process Optimization of DFB Cavities for Organic Laser Diodes

Area of Science:

• Organic electronics
• Photonics
• Materials science

Background:

• The development of organic laser diodes is a key goal in optoelectronics.
• Integrating laser functionalities into organic light-emitting diodes (OLEDs) presents significant fabrication challenges.
• Achieving precise control over micro-cavity resonance is crucial for efficient laser operation.

Purpose of the Study:

• To optimize the multiscale fabrication process for mixed-order distributed-feedback (DFB) micro-cavities.
• To integrate these DFB micro-cavities into OLEDs compatible with nanosecond-short electrical pulse excitation.
• To precisely tune the micro-cavity resonance to the organic gain medium's electroluminescence peak.

Main Methods:

• Combining ultra-short pulsed electrical excitation with laser micro-cavities.
• Utilizing e-beam lithography for nanometer-scale grating patterning in micro-cavity fabrication.
• Employing hydrogen silsesquioxane resist on indium tin oxide anodes with specific exposure doses and development times.

Main Results:

• Optimal DFB micro-cavities were fabricated using specific resist thickness, anode material, and lithography parameters.
• The integration of DFB micro-cavities did not impede the pulsed electrical operability of the OLEDs.
• The devices demonstrated high peak current densities of up to 14 kA/cm².

Conclusions:

• The optimized fabrication process successfully integrates DFB micro-cavities into OLEDs for pulsed electrical operation.
• This work advances the development of organic laser diodes by addressing key integration and tuning challenges.
• The demonstrated high current densities indicate the potential for efficient organic laser diode performance.