An interesting hydrogen sensor based on a Pd/HfO₂/GaO_x/GaN metal-oxide-semiconductor (MOS) structure is fabricated and demonstrated. The HfO₂ and GaO_x layers are prepared using a sputtering approach and hydrogen peroxide (H₂O₂) treatment. The hydrogen sensing characteristics of the studied device are comprehensively studied. Experimentally, good hydrogen sensing characteristics, including a high sensing response of 8.47 × 10⁵, a low detection level of 5 ppm H₂/air, and reversible, short response and recovery times upon exposure to different hydrogen concentrations and temperatures are obtained. The influence of humidity on hydrogen sensing performance is also studied. The exothermic action of the hydrogen adsorption process leads to a decreased hydrogen sensing response at higher temperatures. Consequently, the studied Pd/HfO₂/GaO_x/GaN MOS diode is promising for high-performance hydrogen sensing applications and integration with other GaN-based high-speed devices on a chip.

制造并展示了一种基于Pd / HfO ₂ / GaO _x / GaN金属氧化物半导体（MOS）结构的有趣的氢传感器。使用溅射方法和过氧化氢（H ₂ O ₂）处理来制备HfO ₂和GaO _x层。对所研究装置的氢感测特性进行了综合研究。实验上，良好的氢感测特性，包括8.47×10 ⁵的高感测响应，5 ppm H ₂的低检测水平/空气，并且在暴露于不同的氢气浓度和温度下可获得可逆的，短的响应和恢复时间。还研究了湿度对氢感测性能的影响。氢吸附过程的放热作用导致在较高温度下氢感测响应降低。因此，所研究的Pd / HfO ₂ / GaO _x / GaN MOS二极管有望用于高性能氢感测应用以及与芯片上其他基于GaN的高速器件的集成。