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1.
《Electron Device Letters, IEEE》1980,1(8):154-155
Ga0.47 In0.53 As MESFETs have been fabricated on InP substrates. The low barrier height of Ga0.47 In0.53 As (0.20 eV) which makes simple GaInAs MESFETs at this composition impractical, has been overcome by using thin Al0.48 In0.52 As layers between gate metal and GaInAs active layers. Al0.48 In0.52 As has also been exploited in the form of buffer layers. The double heterostructure FET wafers with single crystal Al gate metal were grown by molecular beam epitaxy (MBE). The 2.75 µm gate length MESFETs showed d.c. transconductance gm = 57 mS mm-1in spite of nonoptimized dimensions. 相似文献
2.
《Electron Device Letters, IEEE》1982,3(8):205-208
We report a selectively doped Ga0.47 In0.53 As/Al0.48 In0.52 As field effect transistor with a 1.2 µm gate length and present a model of two-region operation to analyze its I-V characteristics. This depletion mode transistor shows complete pinch-off and saturation characteristics with a low frequency transconductance of 70 mmho/ mm at 300 K and 125 mmho/mm at 77 K. The theoretical model, which includes the background carriers in the undoped Ga0.47 In0.52 As layer, agrees with the experimental results. 相似文献
3.
《Electron Device Letters, IEEE》1985,6(1):20-21
A novel thin GaAs lattice-mismatched gate Ga0.47 In0.53 As field-effect transistor (LMG-FET) is reported. The device shows an extrinsic dc transconductance of 108 mS/mm for a 1.4-µm gate length and 240-µm gate width. Despite a 3.7-percent, lattice mismatch between GaAs and Ga0.47 In0.53 As, the LMG-FET shows stable operation even at 80°C (with a 13-percent increase in transconductances), exhibits negligible current drift, and suffers very little change in threshold voltages (<0.05 V) under illumination, This technology may find applications in high-speed lightwave transmission as well as high-speed digital circuits. 相似文献
4.
《Electron Device Letters, IEEE》1982,3(6):152-155
We report the first demonstration of a depletion mode modulation doped Ga0.47 In0.53 As field effect transistor. This transistor combines the advantage of modulation doping and the superior material characteristics of Ga0.47 In0.53 As. DC transconductances of 31 mmho/ mm at 300 K and 69 mmho/mm at 77 K have been measured for a device with 5.2µm gate length and 340 µm gate width. An enhanced drift mobility is responsible for 88 percent of the improvement in the transconductance at 77 K and the remaining 12 percent is attributed to an improved ohmic contact. A high performance modulation doped Ga0.47 In0.53 As FET is expected to play an important role in very high speed digital and analog applications. 相似文献
5.
《Electron Device Letters, IEEE》1980,1(9):174-176
MESFETs with GA0.47 In0.53 As active channel grown by MBE on InP substrates were successfully fabricated. Thin layers of MBE grown Al0.48 In0.52 As seperated both the single crystal aluminum gate from the active channel and the active channel from the InP substrate so raising the Schottky barrier height of the gate and confining the electrons to the channel. The MESFETs with 0.6µm long gates and gate-to-source separations of 0.8 um exhibited an average gm of 135 mS mm-1of gate width for Vds = 2V and Vg = 0. This is higher than that reported for GaAs MESFETs with a similar geometry in spite of the intermediate layer between the gate metal and the active layer. 相似文献
6.
《Electron Devices, IEEE Transactions on》1986,33(2):188-191
We demonstrate for the first time a long-wavelength Ga0.47 In0.53 As vertical photoconductive detector with very high gain, low noise, low-bias voltages, high sensitivity, and high-coupling efficiency. The detector consists of an n+ InP, a Fe-doped Ga0.47 In0.53 As, and an n+ Ga0.47 In0.53 As layer grown successively on a semi-insulating InP substrate. The highly resistive active layer sandwiched between two n+ layers creates a uniform electric field perpendicular to the surface, producing a dc gain of 86 at bias voltages as low as 0.5 V. The noise power at 100 MHz is about 11 dB lower than that of a coplanar interdigitated photoconductive detector prepared with undoped GaInAs grown by vapor-phase epitaxy. Preliminary measurements reveal a receiver sensitivity of -28.2 dBm at a bit-error rate of 10-9at 420 Mbit/s and a wavelength of 1.55 µm. 相似文献
7.
《Electron Device Letters, IEEE》1982,3(10):318-319
The first reported growth of the quaternary AlGaInAs on an InP substrate by molecular beam epitaxy had an equal aluminum-to-gallium mole fraction ratio, and exhibited a 5 K bandgap energy of 1.237 eV. This is intermediate between the 5 K band gap energy of Ga0.47 In0.53 As (0.810 eV) and that of Al0.48 In0.52 As (1.56 eV). A Schottky diode and a MESFET were fabricated on this material. 相似文献
8.
Characterization of InGaAs/AlGaAs pseudomorphic modulation-doped field-effect transistors 总被引:1,自引:0,他引:1
《Electron Devices, IEEE Transactions on》1986,33(5):564-571
High-performance pseudomorphic Iny Ga1-y As/Al0.15 - Ga0.85 As (0.05 le y le 0.2 ) MODFET's grown by MBE have been characterized at dc (300 and 77 K) and RF frequencies. Transconductances as high as 310 and 380 mS/mm and drain currents as high as 290 and 310 mA/mm were obtained at 300 and 77 K, respectively, for 1-µm gate lengths and 3-µm source-drain spacing devices. Lack of persistent trapping effects,I-V collapse, and threshold voltage shifts observed with these devices are attributed to the use of low mole fraction Alx Ga1-x As while still maintaining 2DEG concentrations of about 1.3 × 1012cm-2. Detailed microwave S-parameter measurements indicate a current gain cut-off frequency Of 24.5 GHz Wheny = 0.20 , which is as much as 100 percent better than similar GaAs/AlGaAs MODFET structures, and a maximum frequency of oscillation of 40 GHz. These superior results are in part due to the higher electron velocity of InGaAs as compared with GaAs. Velocity field measurement performed up to 3 kV/cm using the magnetoresistance method indicates an electron saturation velocity of greater than 1.7 × 107cm/s at 77 K fory = 0.15 , which is 20 percent higher than GaAs/AlGaAs MODFET's of similar structure. 相似文献
9.
《Electron Device Letters, IEEE》1983,4(10):383-385
We report the first vertical n-p-n heterojunction bipolar transistors formed in the (Al,In)As/(Ga,In)As alloy system. The structures grown by molecular-beam epitaxy (MBE) use a wide band-gap (Eg = 1.44 eV) Al0.48 In0.52 As emitter on a lower band gap (Eg = 0.73 eV) Ga0.47 In0.53 As base 2500 Å in width. Transistors with both abrupt and graded heterojunction emitters were demonstrated with dc current gains of 140 and 280, respectively, at a collector current of 15 mA. The (Al,In)As/(Ga,In)As heterojunction transistors offer the attractive possibility of optical integration with long wavelength lasers and photodetectors. 相似文献
10.
《Electron Devices, IEEE Transactions on》1986,33(6):788-791
Velocity-field characteristics of short samples of n-type Ga0.47 In0.53 As are calculated for 300 K using a Monte Carlo model and recent values of physical constants. The average electron velocity reaches a peak value for a field of about0.5/L (V . cm-1),L being the sample length in centimeters. The peak value increases to about 8.5 × 107cm . s-1for a sample length of 0.1 µm. The values are 1.3-1.6 times the values for GaAs. 相似文献
11.
Ga0.47 In0.53 As has been used to make fast (rt < 1 ns), photodiodes with low dark current (i_{D} < 10^{-8} A) and good quantum efficiency (ηQ ext > 50 percent over the entire1.0-1.7 mu m region of the optical spectrum). The physical properties related to the crystal growth and carrier transport are discussed in this paper in terms of both the design and the operating characteristics of detectors fabricated from this ternary alloy. The results of our work show that Ga0.47 In0.53 As is a material well-suited to several important semiconductor device applications. A comparison to other semiconductor photodiodes shows that Ga0.47 In0.53 As is one of the most sensitive detectors available in the1.0-1.7 mu m wavelength region. One can expect repeater-free transmission in excess of 150 km at 100 Mbits . s-1using these detectors in a digital optical fiber link at the 1.55 μm low-loss (alpha < 0.3 dB . km-1) low-dispersion transmission window. 相似文献
12.
Pearsall T. Piskorski M. Brochet A. Chevrier J. 《Quantum Electronics, IEEE Journal of》1981,17(2):255-259
We have used a Ga0.47 In0.53 As/InP heterostructure to produce a photodiode (area =3 times 10^{-4} cm2) which shows a saturated dark current of 100 pA at 23°C and 1.7 nA at 50°C. At this dark current, these photodiodes have near-unity quantum efficiency at 1.6 μm and show good photoresponse over the1.0-1.65 mu m region of the optical spectrum. 相似文献
13.
《Electron Device Letters, IEEE》1981,2(1):7-9
The first operation of an integrated differential notch-type photoconductor and dual gate (DG) double heterostructure (DH) MESFET in Ga0.47 In0.53 As is reported. The starting material was grown by molecular beam epitaxy on a semi-insulating InP substrate. A 2 mW HeNe laser with a spot diameter Of 0.5 mm could modulate the drain current by 300 µA with the upper gate suitably biased. 相似文献
14.
《Electron Device Letters, IEEE》1981,2(3):73-74
It is demonstrated that inversion-mode n-channel insulated gate field-effect transistors can be made of p-type heteroepitaxially-grown Ga0.47 In0.53 As layers on semi-insulating InP. 相似文献
15.
《Electron Device Letters, IEEE》1981,2(8):193-195
Resistivity increase was compared following various doses of different 100 kV ions implanted into Ga0.47 In0.53 As. The largest resistivity increase of n-type Ge doped GaInAs resulted from a boron ion implant, and increased to a total of 280 times the original resistivity after heating for 15 minutes at 200°C. Boron ion bombardment can be used to isolate devices in a planar GaInAs integrated circuit process. 相似文献
16.
《Electron Devices, IEEE Transactions on》1980,27(7):1256-1262
In order to determine the low-noise potential of microwave MESFET's fabricated from materials other than GaAs, a one-dimensional FET model is employed. From material parameters and device geometry the model enables the calculation of a small-signal equivalent circuit from which performance information is acquired. Material parameters, as predicted from Monte Carlo calculations, are used to simulate 1-µm devices fabricated from GaAs as well as InP, Ga0.47 In0.53 As, InP0.8 As0.2 , Ga0.27 In0.73 P0.4 As0.6 , and Ga0.5 In0.5 As0.96 Sb0.04 . Results obtained from simulations comparing a Ga0.5 In0.5 As0.96 - Sb0.04 device to an equivalent GaAs device indicate that a decrease in minimum noise figure of almost a factor of two is possible. Considerable improvement in noise performance over a GaAs device is also predicted for devices fabricated from Ga0.47 In0.53 As and Ga0.27 In0.73 P0.4 As0.6 . In addition, the quaternary and ternary devices as well as the InP device should exhibit superior gain and high-frequency performance compared to GaAs devices. 相似文献
17.
《Electron Device Letters, IEEE》1983,4(8):275-277
We report the use of an As2 (instead of As4 ) beam during molecular beam epitaxial (MBE) growth of Gax Aly In1-x-y As layers, lattice-matched to InP substrate. We also show that use of the As2 beam improves the room-temperature photoluminescence intensities of both In0.53 Ga0.47 As and Ga0.39 Al0.08 In0.53 As epilayers with more significant improvement for the latter. The substrate temperature employed was ∼ 580°C for both. 相似文献
18.
《Electron Devices, IEEE Transactions on》1978,25(6):619-627
The dc, small-signal microwave, and large-signal switching performance of normally off and normally on Al0.5 Ga0.5 As gate heterojunction GaAs field-effect transistors (HJFET) with submicrometer gate lengths are reported. The structure of both types of devices comprises an n-type 1017-cm-3Sn-doped active layer on a Cr-doped GaAs substrate, a p-type 1018-cm-3Ge-doped Al0.5 Ga0.5 As gate layer and a p+-type 5 × 1018-cm-3Ge-doped GaAs "contact and cap" layer on the top of the gate. The gate structure is obtained by selectively etching the p+-type GaAs and Al0.5 Ga0.5 As. Undercutting of the Al0.5 Ga0.5 As layer results in submicrometer gate lengths, and the resulting p+-GaAs overhang is used to self-align the source and the drain with respect to the gate. Normally off GaAs FET's with 0.5- to 0.7-µm long heterojunction gates exhibit maximum available power gains (MAG) of about 9 dB at 2 GHz. Large-signal pulse measurements indicate an intrinsic propagation delay of 40 ps with an arbitrarily chosen 100-Ω drain load resistance in a 50-Ω microstrip circuit. Normally on FET's with submicrometer gate lengths (∼0.6 µm) having a total gate periphery of 300 µm and a corresponding dc transconductance of 20-30 mmhos exhibit a MAG of 9.5 dB at 8 GHz. The internal propagation delay time measured under the same conditions as above is about 20 ps. 相似文献
19.
《Electron Device Letters, IEEE》1986,7(12):649-651
We report excellent dc and millimeter-wave performance in In0.15 Ga0.85 As/Al0.15 Ga0.85 As pseudomorphic modulation-doped field effect transistors (MODFET's) with 0.25-µm-length gates. Extrinsic transconductances as high as 495 mS/mm at 300 K and unprecedented power performance in the 60-GHz range were observed. Although not yet optimized, excellent low noise characteristics, 0.9 dB, with an associated gain of 10.4 dB at 18 GHz, and a noise figure of 2.4 dB with an associated gain of 4.4 dB at 62 GHz were obtained. This is the best noise performance ever reported for a MODFET in this frequency range. These results clearly demonstrate the superiority of pseudomorphic MODFET structures in high-frequency applications. 相似文献
20.
《Electron Devices, IEEE Transactions on》1987,34(4):782-792
A novel variation on the doped quantum well avalanche photodiode is presented that provides comparable signal-to-noise performance at more realizable material doping requirements. The device consists of repeated unit cells formed from a p-n Al0.48 In0.52 As junction immediately followed by near-intrinsic Ga0.47 In0.53 As and Al0.48 In0.52 As layers. As in the doped quantum well device, the asymmetric unit cell selectively heats the electron distribution much more than the hole distribution prior to injection into the narrow-gap Ga0.47 In0.53 As layer in which impact ionization readily occurs. The effects of various device parameters, such as the junction doping, Ga0.47 In0.53 As and intrinsic Al0.48 In0.52 As layer widths as well as the overall bias on the electron and hole ionization rates, is analyzed using an ensemble Monte Carlo method. From the determination of the ionization rates and the ionization probabilities per stage, P and Q, an optimal device design can be obtained that provides high gain at low multiplication noise. In addition, a structure that operates at less than 5 V bias is presented that can provide moderate gain at very low noise. It is expected that the device designs presented herein can serve either as high-gain low-noise detectors for lightwave communications systems or as moderate-gain low-noise detectors for on-chip application. 相似文献