A new depletion-mode gate recessed A1GaN/InGaN/GaN-high electron mobility transistor （HEMT） with 10 nm thickness of InGaN-channel is proposed. A growth of A1GaN over GaN leads to the formation of two- dimensional el...A new depletion-mode gate recessed A1GaN/InGaN/GaN-high electron mobility transistor （HEMT） with 10 nm thickness of InGaN-channel is proposed. A growth of A1GaN over GaN leads to the formation of two- dimensional electron gas （2DEG） at the heterointerface. High 2DEG density （ns） is achieved at the heterointerface due to a strain induced piezoelectric effect between A1GaN and GaN layers. The electrons are confined in the InGaN-channel without spilling over into the buffer layer, which also reduces the buffer leakage current. From the input transfer characteristics the threshold voltage is obtained as -4.5 V and the device conducts a current of 2 A/mm at a drain voltage of 10 V. The device also shows a maximum output current density of 1.8 A/ram at Vds of 3 V. The microwave characteristics like transconductance, cut-off frequency, max frequency of oscillation and Mason＇s Unilateral Gain of the device are studied by AC small-signal analysis using a two-port network. The stability and power performance of the device are analyzed by the Smith chart and polar plots respectively. To our knowledge this proposed InGaN-channel HEMT structure is the first of its kind.展开更多
The electrical characterization of AlGaN/GaN interface is reported.The dependence of two-dimensional electron gas（2-DEG） density at the interface on the Al mole fraction and thickness of AIGaN layer as well as on th...The electrical characterization of AlGaN/GaN interface is reported.The dependence of two-dimensional electron gas（2-DEG） density at the interface on the Al mole fraction and thickness of AIGaN layer as well as on the thickness of GaN cap layer is presented.This information can be used to design and fabricate AlGaN/GaN based MODFET（modulation doped field effect transistor） for optimum DC and RF characteristics.展开更多
A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave ch...A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave characteristics such as device efficiency and the microwave power generated are computed and compared at D-band（140 GHz center frequency） to see the potentiality of each device under the same operating conditions.It is seen that GaN-based IMPATT devices surpass the Gunn diode in the said frequency region.展开更多
文摘A new depletion-mode gate recessed A1GaN/InGaN/GaN-high electron mobility transistor （HEMT） with 10 nm thickness of InGaN-channel is proposed. A growth of A1GaN over GaN leads to the formation of two- dimensional electron gas （2DEG） at the heterointerface. High 2DEG density （ns） is achieved at the heterointerface due to a strain induced piezoelectric effect between A1GaN and GaN layers. The electrons are confined in the InGaN-channel without spilling over into the buffer layer, which also reduces the buffer leakage current. From the input transfer characteristics the threshold voltage is obtained as -4.5 V and the device conducts a current of 2 A/mm at a drain voltage of 10 V. The device also shows a maximum output current density of 1.8 A/ram at Vds of 3 V. The microwave characteristics like transconductance, cut-off frequency, max frequency of oscillation and Mason＇s Unilateral Gain of the device are studied by AC small-signal analysis using a two-port network. The stability and power performance of the device are analyzed by the Smith chart and polar plots respectively. To our knowledge this proposed InGaN-channel HEMT structure is the first of its kind.
文摘The electrical characterization of AlGaN/GaN interface is reported.The dependence of two-dimensional electron gas（2-DEG） density at the interface on the Al mole fraction and thickness of AIGaN layer as well as on the thickness of GaN cap layer is presented.This information can be used to design and fabricate AlGaN/GaN based MODFET（modulation doped field effect transistor） for optimum DC and RF characteristics.
基金Project supported by the Department of Science and TechnologyGovernment of India through SERC,FIST and TIFAC Program
文摘A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices（TEDs）,namely a Gunn diode and an impact avalanche transit time（IMPATT） device.Microwave characteristics such as device efficiency and the microwave power generated are computed and compared at D-band（140 GHz center frequency） to see the potentiality of each device under the same operating conditions.It is seen that GaN-based IMPATT devices surpass the Gunn diode in the said frequency region.
