Investigation of High-Sensitivity pH Sensor Based on Au-Gated AlGaN/GaN Heterostructure

Ye, Minjie1; Sun, Jianwen2; Zhan, Teng3; Sokolovskij, Robert4; Zhang, Yulong2; Wei, Jiangtao2; Chen, Shaomin1; Liu, Zewen2

2024-07-01

10.3390/app14146131

APPLIED SCIENCES-BASEL   影响因子和分区

2076-3417

A high-sensitivity pH sensor based on an AlGaN/GaN high-electron mobility transistor (HEMT) with a 10 nm thick Au-gated sensing membrane was investigated. The Au nanolayer as a sensing membrane was deposited by electron-beam evaporation and patterned onto the GaN cap layer, which provides more surface-active sites and a more robust adsorption capacity for hydrogen ions (H+) and hydroxide ions (OH-) and thus the sensitivity of the sensor can be significantly enhanced. A quasi-reference electrode was used to minimize the sensing system for the measurement of the microliter solution. The measurement and analysis results demonstrate that the fabricated sensor exhibits a high potential sensitivity of 58.59 mV/pH, which is very close to the Nernstian limit. The current sensitivity is as high as 372.37 mu A/pH in the pH range from 4.0 to 9.18, under a 3.5 V drain-source voltage and a 0 V reference-source voltage. Comparison experiments show that the current sensitivity of the Au-gated sensor can reach 3.9 times that of the SiO2-gated sensor. Dynamic titration experiments reveal the pH sensor's ability to promptly respond to immediate pH variations. These findings indicate that this pH sensor can meet most application requirements for advanced medical and chemical analysis.

pH sensor AlGaN/GaN Au HEMT

SCI ; EI

英语

其他

Chemistry ; Engineering ; Materials Science ; Physics

Chemistry, Multidisciplinary ; Engineering, Multidisciplinary ; Materials Science, Multidisciplinary ; Physics, Applied

WOS:001276592200001

MDPI

20243116778395

Drain current ; Gallium nitride ; Gold deposits ; High electron mobility transistors ; III-V semiconductors ; pH ; pH sensors ; Silica ; Titration

Heavy Metal Mines:504.3 ; Precious Metals:547.1 ; Semiconducting Materials:712.1 ; Semiconductor Devices and Integrated Circuits:714.2 ; Chemistry:801 ; Chemistry, General:801.1 ; Inorganic Compounds:804.2 ; Special Purpose Instruments:943.3

Web of Science

1.Tsinghua Univ, Dept Engn Phys, Beijing 100084, Peoples R China
2.Tsinghua Univ, Sch Integrated Circuits, Beijing 100084, Peoples R China
3.Chinese Acad Sci, Inst Semicond, Res & Dev Ctr Wide Bandgap Semicond, Beijing 100083, Peoples R China
4.Southern Univ Sci & Technol, Sch Microelect, Shenzhen 518055, Peoples R China

Ye, Minjie,Sun, Jianwen,Zhan, Teng,et al. Investigation of High-Sensitivity pH Sensor Based on Au-Gated AlGaN/GaN Heterostructure[J]. APPLIED SCIENCES-BASEL,2024,14(14).

Ye, Minjie.,Sun, Jianwen.,Zhan, Teng.,Sokolovskij, Robert.,Zhang, Yulong.,...&Liu, Zewen.(2024).Investigation of High-Sensitivity pH Sensor Based on Au-Gated AlGaN/GaN Heterostructure.APPLIED SCIENCES-BASEL,14(14).

Ye, Minjie,et al."Investigation of High-Sensitivity pH Sensor Based on Au-Gated AlGaN/GaN Heterostructure".APPLIED SCIENCES-BASEL 14.14(2024).