共查询到20条相似文献,搜索用时 109 毫秒
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研制了Al0.24Ga0.76As/In0.22Ga0.78As单平面掺杂PHEMT器件(SH-PHEMT)和双平面掺杂PHEMT器件(DH-PHEMT),并对其特性进行了比较.由于采用了双异质结、双平面掺杂的设计,DH-PHEMT能将载流子更好地限制在沟道中,得到更大的二维电子气浓度和更均匀的二维电子气分布,这些都有利于提高器件的性能.因此,DH-PHEMT器件具有更好的线性度,在较大的栅压范围内具有高的跨导和更大的电流驱动能力.这说明DH-PHEMT器件更加适用于高线性度应用的微波功率器件. 相似文献
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研制了Al0 .2 4 Ga0 .76 As/ In0 .2 2 Ga0 .78As单平面掺杂PHEMT器件(SH - PHEMT)和双平面掺杂PHEMT器件(DH- PHEMT) ,并对其特性进行了比较.由于采用了双异质结、双平面掺杂的设计,DH- PHEMT能将载流子更好地限制在沟道中,得到更大的二维电子气浓度和更均匀的二维电子气分布,这些都有利于提高器件的性能.因此,DH- PHEMT器件具有更好的线性度,在较大的栅压范围内具有高的跨导和更大的电流驱动能力.这说明DH-PHEMT器件更加适用于高线性度应用的微波功率器件. 相似文献
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Ga N有较 Ga As更宽的禁带、更高的击穿场强、更高的电子饱和速度和更高的热导率 ,Al Ga N/Ga N异质结构不仅具有较 Ga As PHEMT中Al Ga As/In Ga As异质结构更大的导带偏移 ,而且在异质界面附近有很强的自发极化和压电极化 ,极化电场在电子势阱中形成高密度的二维电子气 ,这种二维电子气可以由不掺杂势垒层中的电子转移来产生。理论上 Al Ga N/Ga N HEMT单位毫米栅宽输出功率可达到几十瓦 ,而且其宽禁带特点决定它可以承受更高的工作结温 ,作为新一代的微波功率器件 ,Al Ga N/Ga N HEMT将成为微波大功率器件发展的方向。采… 相似文献
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In this work, the performance of Lg=22 nm In0.75Ga0.25As channel-based high electron mobility transistor (HEMT) on InP substrate is compared with metamorphic high electron mobility transistor (MHEMT) on GaAs substrate. The devices features heavily doped In0.6Ga0.4As source/drain (S/D) regions, Si double δ-doping planar sheets on either side of the In0.75Ga0.25As channel layer to enhance the transconductance, and buried Pt metal gate technology for reducing short channel effects. The TCAD simulation results show that the InP HEMT performance is superior to GaAs MHEMT in terms of fT, fmax and transconductance (gm_max). The 22 nm InP HEMT shows an fT of 733 GHz and an fmax of 1340 GHz where as in GaAs MHEMT it is 644 GHz and 924 GHz, respectively. InGaAs channel-based HEMTs on InP/GaAs substrates are suitable for future sub-millimeter and millimeter wave applications. 相似文献
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Ritesh Gupta 《Microelectronics Journal》2006,37(9):919-929
In the proposed work the model has been formulated for discretized doped HEMT, where the conventional uniformly doped, pulsed doped and delta doped structure are the special cases. An expression for sheet carrier density has been formulated considering the effect of doping-thickness product and has been extended to calculate drain current, transconductance, capacitance and cut-off frequency of the device. The model also takes into account the non-linear relationship between sheet carrier density and quasi Fermi energy level to validate it from subthreshold region to high conduction region. The results so obtained have been compared with pulsed doped structure to validate the model. The analysis concentrates on the distance of doping from the heterojunction and gate electrode. Different design criteria have been given to dope the carriers (amount and distance) in different regions to optimize the performance for higher sheet carrier density/parallel conduction voltage/effective parallel conduction voltage (Vc−Voff) to increase the transconductance, cut-off frequency and reliability of the device. 相似文献
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Mesquida Kusters A. Funke T. Sommer V. Wuller R. Brittner S. Kohl A. Heime K. 《Electronics letters》1993,29(10):841-842
High performance InP/In/sub 0.75/Ga/sub 0.25/As/InP pseudomorphic double heterojunction (DH) HEMTs with a gate length of 0.5 mu m are reported. Both DC and RF characteristics of this new type of Al-free HEMT demonstrate its suitability for microwave applications.<> 相似文献
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An improved slot etch technique based on an Si planar doped layer has been applied to gate recessing in the fabrication of AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistors (HEMTs). The devices exhibited comparable gm with much better breakdown and leakage behaviour than conventional pseudomorphic HEMT devices 相似文献
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A physically based technique for modeling HEMT structure S-parameters is presented. The core of the model is directly dependent on the HEMT wafer structure and the physical gate length. The model accurately predicts the device's S-parameters as a function of the applied gate bias. The physical basis facilitates the modeling of different types of HEMT structures. Measured S-parameters and simulation results over a frequency range of 1 to 25 GHz are presented for three different HEMT structures: uniformly doped, GaAs channel; pulse-doped, GaAs channel; and uniformly doped, strained InGaAs channel 相似文献
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《Electron Device Letters, IEEE》1985,6(7):341-343
A microwave power high electron mobility transistor (HEMT) has been developed and tested in theK -band frequency range. The HEMT has a unique configuration of a selectively low-doped (AlGa)As/GaAs/(AlGa)As double heterojunction resulting in both capability of high-current density and high gate breakdown voltage. The structure showed electron mobility of 6800 cm2/V.s and two-dimensional (2-D) electron density as high as 1.2 × 1012cm-2at room temperature. An output power of 660 mW (550 mW/mm) with 3.2-dB gain and 19.3-percent power added efficiency was achieved at 20 GHz with 1-µm gate length and 1.2-mm gate periphery. A similar device with 2.4-mm gate width produced an output power of 1 W with 3-dB gain and 15.5-percent efficiency. These results offer microwave high power capability in a double-heterojunction HEMT (DH-HEMT). 相似文献
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《Electron Devices, IEEE Transactions on》1970,17(5):413-420
Assuming a state-of-the-art microwave planar geometry, the maximum frequency of oscillation has been calculated for GaAs-Ge heterojunction transistors utilizing either doped or high-resistivity space-charge-limited emitters. This is compared with a Ge homojunction transistor of the same geometry. A detailed equivalent circuit is used which accounts for the parasitics of the chip. It is shown that if chip parasitics are neglected, GaA-Ge devices should outperform Ge devices by about 4 to 1 in power gain. In the geometry assumed, however both heterojunction and homojunction transistors are limited by wafer parasitics, particularly base contact resistance. The calculated figures of merit of the two types of devices are therefore quite similar. 相似文献
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《Solid-state electronics》1987,30(11):1197-1203
A two-dimensional numerical drift-diffusion model for the High Electron Mobility Transistor (HEMT) is presented. Special attention is paid to the modeling of the current flow over the heterojunction. A finite difference scheme is used to solve the equations, and a variable mesh spacing was implemented to cope with the strong variations of functions near the heterojunction. Simulation results are compared to experimental data for a 0.7 μm gate length device. Small-signal transconductances and cut-off frequency obtained from the 2-D model agree well with the experimental values from S-parameter measurements. It is shown that the numerical models give good insight into device behaviour, including important parasitic effects such as electron injection into the bulk GaAs. 相似文献