Improved Reliability of InGaN-Based Light-Emitting Diodes by HfO2 Passivation Layer

Area of Science:

• Materials Science
• Solid-State Physics
• Optoelectronics

Background:

• Gallium Nitide (GaN)-based light-emitting diodes (LEDs) are crucial for modern lighting and displays.
• Improving their leakage current and reliability is essential for device performance and longevity.

Purpose of the Study:

• To investigate the effectiveness of a hafnium oxide (HfO2) passivation layer in enhancing GaN-based LEDs.
• To analyze the impact of HfO2 on electrical, optical, and reliability characteristics.

Main Methods:

• Fabrication of GaN-based LEDs with an HfO2 passivation layer.
• Characterization using current-voltage (I-V) measurements.
• Optical power measurements to assess performance.
• Reliability testing to evaluate device stability.

Main Results:

• The HfO2 passivation layer effectively suppressed leakage current in GaN-based LEDs.
• No degradation in optical power was observed with the HfO2 layer.
• Improved reliability was attributed to the low deposition temperature of sputtered HfO2, preventing hydrogen plasma diffusion and Mg-H complex formation.

Conclusions:

• HfO2 is a promising passivation material for GaN-based LEDs.
• The low-temperature sputtering process for HfO2 is key to achieving enhanced reliability.
• This approach offers a viable solution for developing more robust and efficient GaN-based optoelectronic devices.