用于消毒副产物检测的N极性面GaN基复合背势垒异质结HEMT传感器研究

The disinfection by-products (DBPs) produced during drinking water disinfection can induce cancer, abnormality and sudden change, which are very harmful to human health. Therefore, it is significant to develop sensor for real-time and fast detection of DBPs. This applied project will improve the sensitivity of GaN-based HEMT sensor by using the features of N-polar GaN/(AlN, AlInN, AlGaN) heterostructure with AlN/AlInN/AlGaN combinational back barrier that higher surface chemical activity and shorter sensing distance, compared to the Ga-polar AlGaN/GaN heterostructure. The selective recognition ability of this sensor can be enhanced by the surface modification on the sensing area of HEMT with imprinted polymer. A series of important basic issues, such as the optimized design of N-polar GaN/(AlN, AlInN, AlGaN) heterostructure, modulating mechanism of 2DEG concentration by surface charge and surface potential and the selective recognition of specific DBPs by imprinted polymer will be studied systematically. The final goal of this project is to achieve trace, fast and accurate detection of DBPs in drinking water. Meanwhile, the project will establish the intrinsic physical correlation between the detection performance and device structure, material structure and the characteristic parameters of functional modified materials, providing theoretical basis and technical support for broader application of the GaN-based HEMT sensor.

饮用水消毒过程中产生的消毒副产物对人体有致癌、致畸、致突变等严重危害，研发可实时快速准确检测消毒副产物的传感器具有重要意义。本申请项目拟利用N极性面GaN/(AlN, AlInN, AlGaN)复合背势垒异质结构相比Ga极性面AlGaN/GaN异质结具有更强的表面化学活性、更短的传感距离等特点提高GaN基HEMT传感器的灵敏度，通过分子（离子）印迹聚合物材料对HEMT器件进行表面功能化改性提高传感器的选择识别能力。系统研究N极性面GaN基复合背势垒异质结的优化设计、表面电荷及表面电势对二维电子气浓度的调控机理、印迹聚合物材料对特定消毒副产物的选择性识别等重要基础问题，实现对饮用水中消毒副产物的微量快速准确检测。同时，建立GaN基HEMT传感器的检测性能与器件结构、材料结构、功能化修饰材料特征参数等参量之间的内在物理关联，为GaN基HEMT传感器实现更广阔的应用提供理论依据和技术支撑。

饮用水消毒过程中产生的消毒副产物对人体具有致癌、致畸、致突变等严重危害，研发可实时快速准确检测消毒副产物的传感器具有重要意义。在国家自然科学基金的资助下，课题组主要开展了表面电荷对Ga极性面和N极性面GaN基HEMT内沟道二维电子气浓度的调控机理、器件的材料结构参数与栅极结构对表面电荷调控器件性能的影响及其规律、N极性面HEMT器件结构优化设计、表面改性所用印迹聚合物对特定物质的选择性识别等关键基础科学问题的研究。通过在HEMT传感器中集成参比器件，有效降低了器件的电学噪声与等效电阻，提高了器件的检测灵敏度与工作稳定性。制备出对三氯乙酸根、汞离子具有选择性识别功能的聚合物材料，实现了HEMT器件对三氯乙酸、pH值等的高灵敏检测。同时，确立了GaN基HEMT器件的表面传感机理以及传感性能与器件结构参数的内在物理关联，为GaN基HEMT传感器的进一步发展与更广阔的应用提供了理论依据。部分研究成果已正式发表在物理学报（1篇）、Optics Express（1篇）、IEEE Sensors Journal（1篇）、Journal of Alloys and Compounds（1篇）、Current Applied Physics（1篇）、 RSC Advances（2篇）、Physica Status Solidi-Rapid Research Letters（1篇）、Chinese Physics B（1篇）等SCI收录的期刊上。