Dual gate AlGaN/GaN MOS-HEMT biosensor for electrical detection of biomolecules-analytical model

Abstract

This paper proposes an analytical model for a Dual gate AlGaN/GaN MOS-HEMT biosensor for electrical detection of neutral species such as Biotin, Keratin, ChOx, and Zein. When only one subband is occupied and the AlGaN layer is assumed to have been fully ionized, the Fermi-Dirac statistic and 2D state density are used to produce a self-consistent calculation of the carrier density in the quantum well at the interface.It is done by analyzing the impact of biomolecule concentration by inserting a biomolecule of appropriate dielectric permittivity in the cavity area beneath the gate region. The impact of cavity length has been analyzed on the sensor's performance. The proposed device significantly changes the channel potential, transconductance, drain current, and threshold voltage.Dual gate structures offer superior resistance to short channel effects. Due to enhanced transport characteristics, high carrier mobility, drain current, and a variety of other factors, double gate MOS HEMT outperforms single gate MOS HEMT.The maximaltransconductance,drain on sensitivity, and the maximaldrain currentthat has been attained in this work is 0.017S, 0.22 and 0.129mA, respectively, for biomolecule concentration, Nb=3×10¹².Among all the biomolecules used in this study, Keratin has achieved the maximum shift in threshold voltage and transconductance of 0.4V and 0.016S. The increase in current for Keratin, Biotin, Zein, and ChOx is 0.67%, 78%, 17%, and 42%, respectively, from single to Dual gate AlGaN/GaN MOS-HEMT. SiO2, Al2O3, and HfO2oxides have been compared by filling them in the left side of the cavity. Dual gate AlGaN/GaN MOS-HEMT biosensor presents an opportunity to develop robust, low-cost, specific detection and analysis of neutral biomolecule.The analytical model provides good results for drain current according to the comparison of simulation and analytical model findings.

The study of N-polar GaN/InAlN MOS-HEMT and T-gate HEMT biosensors

“…The sensitivities for Uricase, Streptavidin, Protein, Biotin, ChOx, and APTES biomolecules are 4.9%, 10%, 13.4%, 14.6%, 20%, and 22% respectively. Table 3 presents the ∆I DS of N-polar GaN/InAlN MOS-HEMT biosensor and previous reports [26,45,46] for various neutral biomolecules. It can be seen from table 3 that the ∆I DS obtained from this work is higher than the previous studies.…”

An integrated wearable sticker based on extended-gate AlGaN/GaN high electron mobility transistors for real-time cortisol detection in human sweat

“…17,[19][20][21][22][23] Among FET-based biosensors, AlGaN/GaN high electronmobility transistor (HEMT) stands out as a more suitable choice for bio-sensing due to its non-toxicity, biocompatibility, and chemical stability. [24][25][26][27][28][29] Above all, the two-dimensional electron gas (2DEG) in the AlGaN/GaN HEMT sensor is a located in close proximity to the surface, rendering it highly responsive to variations in surface potential. In recent years, AlGaN/GaN HEMT sensors have been successfully employed for the detection of proteins (biomarkers, antigens), [30][31][32] ions, 29,[33][34][35][36] DNA hybridization, 37 and pH [38][39][40][41] in solution or serum samples due to their various advantages mentioned above.…”

Sensitivity improvement in gate engineered technique dielectric modulated GaN MOSHEMT with InGaN notch for label-free biosensing

“…To overcome these difficulties, AlGaN/GaN-MOSHEMT devices are proposed to reduce gate leakage with enhancement mode operation. These devices play a significant role in biosensing applications, enabling biomolecule detection faster and more accurately [7].…”

“…Dielectric-modulated (DM) MOSHEMTs work on the modulation of dielectric constants and surface charges, leading to threshold voltage shifts, thereby altering the transconductance of the device [7][8][9]. Normally, embedding biomedical compounds by etching part of the oxide below the gate electrode leads to variation in effective dielectric constant, causing a change in current and paving the way for the detection of biomolecules precisely.…”