Current-Voltage Characteristics and Transconductance of Undoped Algan/Gan Mishfet’s
Novel Analytical model for current-voltage characteristics and transconductance of undoped AlGaN/GaN MISHFET’s and performance comparison with different high-k dielectrics
Rangababu Ganta1, Saptarsi Ghosh2 and Dhrubes Biswas1,2
1Department of Electrical & Electronics Communication Engineering, IIT Kharagpur, Kharagpur -721302, India
2Advance Technology Development Center, IIT Kharagpur, Kharagpur -721302, India
E-mail: rangababu.ganta@gmail.com
Abstract. In this paper an improved charge controlled model of undoped ,lattice mismatched AlGaN / GaN MISHFET is presented .This model gives an accurate estimation of the 2-DEG sheet carrier concentration at the interface contributed entirely by spontaneous and piezoelectric polarization .The dependence of this sheet carrier density on Al composition and the insulator thickness is investigated in detail. Based on these developments an analytical current - voltage model incorporating Source/Drain parasitic resistance is presented. Also, the non-linear behavior of saturated Drain current is properly formulated and computation of transconductance is carried out for the same. Even without any intentional doping the proposed model exhibits fairly encouraging values of output current and conductance.
Introduction
With the impulsive rise of mobile computing and communication sector, high power RF devices are destined to play significant role in consumer electronics. Wide band gap semiconductors such as GaN are strong contender for high power electronic and optoelectronic circuits. Larger direct band gap (3.4 eV), as compared to Silicon (1.1 eV) and GaAs (1.4 eV) leads to higher values of critical fields and breakdown voltages. Recently GaN/AlGaN based heterostructure devices are grabbing much attention of both material and device community due to excellent electron transport properties and high sheet carrier densities. In GaN/AlGaN based systems a significant amount of charge concentration is found to originate at
Rangababu Ganta1, Saptarsi Ghosh2 and Dhrubes Biswas1,2
1Department of Electrical & Electronics Communication Engineering, IIT Kharagpur, Kharagpur -721302, India
2Advance Technology Development Center, IIT Kharagpur, Kharagpur -721302, India
E-mail: rangababu.ganta@gmail.com
Abstract. In this paper an improved charge controlled model of undoped ,lattice mismatched AlGaN / GaN MISHFET is presented .This model gives an accurate estimation of the 2-DEG sheet carrier concentration at the interface contributed entirely by spontaneous and piezoelectric polarization .The dependence of this sheet carrier density on Al composition and the insulator thickness is investigated in detail. Based on these developments an analytical current - voltage model incorporating Source/Drain parasitic resistance is presented. Also, the non-linear behavior of saturated Drain current is properly formulated and computation of transconductance is carried out for the same. Even without any intentional doping the proposed model exhibits fairly encouraging values of output current and conductance.
Introduction
With the impulsive rise of mobile computing and communication sector, high power RF devices are destined to play significant role in consumer electronics. Wide band gap semiconductors such as GaN are strong contender for high power electronic and optoelectronic circuits. Larger direct band gap (3.4 eV), as compared to Silicon (1.1 eV) and GaAs (1.4 eV) leads to higher values of critical fields and breakdown voltages. Recently GaN/AlGaN based heterostructure devices are grabbing much attention of both material and device community due to excellent electron transport properties and high sheet carrier densities. In GaN/AlGaN based systems a significant amount of charge concentration is found to originate at
References: Takehiko Nomura, Hiroshi Kambayashi, Mitsuru Masuda,Sonomi Ishii, Nariaki Ikeda, Jiang Lee, and Seikoh Yoshida 2006 IEEE Transactions on Electron Devices 53. K. H. Lee, C. Chang and S. J. Chang 2011 Applied Physics Letters 99. Saptarsi Ghosh,Servin Rathi, Partha Mukhopadhyay, Sanjay kumar Jana,and Dhrubes Biswas * 2012 International Conference on Advances in Engineering and Technology ICAET 2012,Conference Proceedings. F.Schwierz 2005 Solid State Electron. 49 889-95. Miao Li and Yan Wang 2008 IEEE Transactions on Electron Devices 55 261-67.