共查询到20条相似文献,搜索用时 31 毫秒
1.
《Electron Devices, IEEE Transactions on》1987,34(7):1448-1455
Doped-channel MIS-like FET's (DMT's) based upon an i-AlGaAs/n-GaAs structure have been investigated in detail for the purpose of clarifying their properties and performance potentialities. The DMT is unique in having two operation modes, a depletion-layer modulation mode and an electron accumulation mode, both of which are experimentally demonstrated through capacitance-voltage characteristics. Analytical and experimental results shows that the maximum drain current IDSmax is more than 2.5 times that for a conventional n-AlGaAs/GaAs 2DEGFET. gmmax and IDsmax values obtained for 0.5- µm gate DMT's are very high, 310 mS/mm (410 mS/mm) and 650 mA/mm (800 mA,/mm) at 300 K (77 K), respectively, fmax is 48 GHz. fT is as large as 45 GHz, which is the best data ever reported in 0.5-µm gate FET's. Moreover, the estimated electron saturation velocity is outstandingly large, 1.5 × 107cm/s (2 × 107cm/s) at 300 K (77 K), even for a thin GaAs channel layer with a 3 × 1018cm-3doping level, while Hall electron mobility is not reasonably so high, being typically 1850 cm2/V . s (1650 cm2/V . S). Preliminary power performances are also studied at 28.5 GHz. An 18-dBm (225-mW/mm) saturation output power, 6.4-dB linear gain, and 15-percent power added efficiency are achieved. A further performance improvement may be easily accomplished by gate length reduction, structure optimization, and so on. Consequently, it has been proved that DMT's have great feasibility for high-speed and high-frequency high-power device applications. 相似文献
2.
3.21 ps ECL gate using InP/InGaAs DHBT technology 总被引:2,自引:0,他引:2
A new circuit configuration for an emitter-coupled logic (ECL) gate that can reduce propagation delay time has been demonstrated. Nineteen-stage ring oscillators were fabricated using InP/InGaAs double-heterojunction bipolar transistors (DHBTs) with cutoff frequency f/sub T/ and maximum oscillation frequency f/sub max/ of about 232 and 360 GHz, respectively, to evaluate the speed performance of the proposed ECL gate. The minimum propagation delay is 3.21 ps/gate. The proposed ECL gate is about 8% faster than the conventional ECL gate. 相似文献
3.
Kondo M. Oda K. Ohue E. Shimamoto H. Tanabe M. Onai T. Washio K. 《Electron Devices, IEEE Transactions on》1998,45(6):1287-1294
Ultra-low-power and high-speed SiGe base bipolar transistors that can be used in RF sections of multi-GHz telecommunication systems have been developed. The SiGe base and a poly-Si/SiGe base-contact were formed by selective growth in a self-aligned manner. The transistors have a very small base-collector capacitance (below 1 fF for an emitter area of 0.2×0.7 μm) and exhibit a high maximum oscillation frequency (30-70 GHz) at low current (5-100 μA). The power-delay product of an ECL ring oscillator is only 5.1 fJ/gate for a 250-mV voltage swing. The maximum toggle frequency of a one-eighth static divider is 4.7 GHz at a switching current of 68 μA/FF 相似文献
4.
Investigates the characteristics of a new injection transistor logic (ITL) fabricated by vapour-phase epitaxy and ion implantation. The maximum current gain of the Si-ITL-inverter is about 150. The propagation delay t/sub pd/ was determined by the ring oscillator and maximum frequency method. At a power of 100 mu W per gate for this inverter, t/sub pd/ is about 500 ps and 850 ps for 60 mu W. In the high-speed ITL structure t/sub pd/ is about 300 ps for 120 mu W.<> 相似文献
5.
6.
《Microwave and Wireless Components Letters, IEEE》2008,18(11):752-754
7.
AlGaAs/GaAs heterojunction bipolar transistors fabricated using a self-aligned dual-lift-off process
《Electron Device Letters, IEEE》1987,8(7):303-305
This paper describes a self-aligned heterojunction-bipolar-transistor (HBT) process based on a simple dual-lift-off method. Transistors with emitter width down to 1.2 µm and base doping up to 1 × 1020/cm3have been fabricated. Extrapolated current gain cutoff frequency ft of 55 GHz and maximum frequency of oscillationf_{max} of 105 GHz have been obtained. Current-mode-logic (CML) ring oscillators with propagation delays as low as 14.2 ps have been demonstrated. These are record performance results for bipolar transistors. The dual-lift-off process is promising for both millimeter-wave devices and large-scale integrated circuit fabrication. 相似文献
8.
A circuit of a ring voltage controlled oscillator (VCO), which is to be used in high-speed phase-locked loop (PLL) systems integrated into programmable logic integrated circuits, is proposed. The maximum operating frequency of a VCO in 180 nm CMOS is shown by simulation to be able to reach 2 GHz in all operating conditions with the phase noise being ?99 dB/Hz and detuning frequency being 1 MHz. 相似文献
9.
Bogdashov A. Denisov G. Lukovnikov D. Rodin Y. Hirshfield J. 《Microwave Theory and Techniques》2005,53(10):3152-3155
A new millimeter-wave resonant ring using a traveling TE/sub 01/ wave in an oversized cylindrical waveguide has been developed for high-power tests of accelerator components. Novel low-loss miter bends with flat mirrors that utilize mode mixing to minimize losses were used in the resonant ring. Low-power measurements show a maximum effective power gain factor that exceeds 35:1 at the operating frequency of 34.272 GHz. Total quality factor is approximately 21400, and the reflection coefficient from the input to the ring resonator is less than 1%. 相似文献
10.
Adjustable frequency dielectric resonator antenna 总被引:1,自引:0,他引:1
An easy method of tuning the resonant frequency of cylindrical and ring dielectric resonator (DR) antennas using different diameters of conducting plates is presented. This technique can tune a DR antenna to operate at the design frequency without changing antenna performance. The maximum frequency tuning range can reach up to 300-500 MHz 相似文献
11.
《Microwave and Wireless Components Letters, IEEE》2009,19(5):314-316
12.
研究了连续激光注入时无源环形腔的背向散射特性。首先,分析了注入光与无源腔频率完全匹配时,正向光和背散光振幅的稳态解,以及充光和快速关断过程中正向光和背散光振幅随时间的演化。其次,推导了无源腔中正向光和背向散射光的峰值半宽。最后,讨论了正向光和背散光随注入光频率扫描速度的变化。发现在环形腔中,总背向散射光强要比单圈背向散射光强大,背向散射光的峰值半宽为正向光的0.64倍。这些发现对背向散射精密测量、扫频法测腔损具有一定的参考作用。 相似文献
13.
《Electron Device Letters, IEEE》1984,5(7):226-227
A GaAs integrated circuit has been designed and fabricated to regenerate digital data at gigabit per second rates. The circuit architecture is direct-coupled FET logic (DCFL), and the fabrication is by self-aligned etched gate on CVD epitaxial material. The circuit includes a moderate-gain input amplifier with threshold adjustment, a clocked D flip-flop for data sampling and storage, and an output buffer for driving low impedance transmission lines. Dynamic performance measurements include correct regeneration of pseudorandom data at 2.0 Gbit/s, the maximum allowed by available instrumentation, and 1010... data at 2.4 Gbit/s. Rise/fall times below 150 ps into 50 Ω were observed. A minimum gate delay of 17.8 ps and a maximum toggle frequency of 3.8 GHz were measured with associated ring oscillator and binary frequency divider circuits, respectively. 相似文献
14.
《Electron Device Letters, IEEE》1985,6(2):83-85
A single clock master-slave frequency divider circuit was designed and fabricated using GaAs MESFET's in the direct-coupled FET logic (DCFL) circuit architecture. At room temperature, the maximum operating frequency was 6.2 GHz at a power consumption of 3.5 mW/gate. The complete divider circuit and buffer amplifier was realized in a 65 × 165 µm2area. The MESFET's were fabricated using Si ion implantion directly into GaAs wafers and used a self-aligned recessed gate. The nominal gatelength was 0.6 µm. Corresponding fabricated ring oscillator circuits showed minimum gate delays of 18.5 ps at 3.1 mW/gate for fan-out of one at 300 K and 15.2 ps at 3.5 mW/gate at 77 K. 相似文献
15.
谐振腔光纤陀螺信号检测方法的研究 总被引:11,自引:5,他引:11
谐振腔光纤陀螺(R—FOG)是利用光学Sagnac效应实现对转动检测的一种高精度的惯性传感器件。在谐振腔光纤陀螺系统中,信号检测系统占有非常重要的地位,其检测精度的大小直接影响陀螺的分辨率。光纤环形谐振腔是谐振腔光纤陀螺的核心敏感部件。采用两种频率的锯齿波组合调制,考虑激光器有限光谱线宽条件下,采用洛仑兹线型描写光纤环形谐振腔的输出光强表达式。针对输出光强与谐振频率偏差在靠近谐振点附近的近似线性关系,利用多次反馈频率操作来依次跟踪谐振腔光纤陀螺顺时针和逆时针光束的谐振点,从而避免了谐振频率偏差复杂的求根算法。仿真结果表明,多次反馈频率操作,可以较快地锁定到谐振点。 相似文献
16.
Frequency stabilization of laser diode using a frequency-locked ring resonator to acetylene gas absorption lines 总被引:1,自引:0,他引:1
Y. Sakai I. Yokohama T. Kominato S. Sudo 《Photonics Technology Letters, IEEE》1991,3(10):868-870
The frequency stabilization of a 1.5 mu m distributed-feedback (DFB) laser diode using a planar lightwave circuit (PLC) ring resonator whose resonant frequency is locked to /sup 12/C/sub 2/H/sub 2/ and /sup 13/C/sub 2/H/sub 2/ gas absorption lines is described. The resonant frequency of PLC ring resonator was stabilized within a 5 MHz peak-to-peak fluctuation. With this ring resonator the outer frequency fluctuation of the DFB laser diode was stabilized within 10 MHz at every resonant frequency at 5 GHz intervals. The stability demonstrated is as good as the method using molecular absorption lines as a reference. The stabilized frequency can be selected at any point on the optical resonant peaks of the optical resonator.<> 相似文献
17.
《Electron Devices, IEEE Transactions on》1986,33(5):543-547
Frequency dividers and ring oscillators have been fabricated with submicrometer gates on selectively doped AIGaAs/GaAs heterostructure wafers. A divide-by-two frequency divider operated up to 9.15 GHz at room temperature, dissipating 25 mW for the whole circuit at a bias voltage of 1.6 V, with gate length ∼ 0.35 µm. A record propagation delay of 5.8 ps/gate was measured for a 0.35-µm gate 19- stage ring oscillator at 77 K, with a power of 1.76 mW/gate, and a bias voltage of 0.88 V. The maximum switching speed at room temperature was 10.2 ps/gate at 1.03 mW/gate and 0.8 V bias, for a ring oscillator with the same gate length. With a range of gate lengths on the same wafer fabricated by electron-beam lithography, a clear demonstration of gate-length dependence on the propagation delay was observed for both dividers and ring oscillators. 相似文献
18.
A self-aligned metal/IDP (SMI) technology is proposed to reduce the external base resistance and to enable fabrication of high-speed bipolar transistors. This SMI technology produces a self-aligned base electrode of stacked layers of metal and in situ-doped poly-Si (LDP) with a small thermal budget by selective tungsten CVD. It provides the low base resistance and a shallow link base for the small-collector capacitance and the high-cutoff frequency. The base resistance is reduced to a half that in a transistor having a conventional poly-Si base electrode. A maximum oscillation frequency of 81 GHz and a 12.2-ps gate delay time in an ECL ring oscillator at a voltage swing of 250 mV were achieved by using the SMI technology even with an ion-implanted base 相似文献
19.
Broadbanding of corrugated conical horns is investigated with the ring-loaded corrugated circular waveguide (RCWG) structure devised by the authors. The useful frequency bandwidth in which the corrugated horn is effective for the improvement of antenna properties is limited by the frequency characteristics of the horn-aperture field and input VSWR of the horn. By the precise analysis of the RCWG, the maximum frequency range in which the desirable field is obtained is much wider than that in the conventional corrugated circular waveguide, and is achieved almost independent of ring thickness, when ring width is about 20 percent of slot depth. The characteristic impedance of the RCWG is nearly equal to that of the homogeneous circular waveguide when ring thickness becomes large. Therefore, a good transformer between the RCWG and the homogeneous circular waveguide is achieved by increasing ring thickness from the RCWG toward the homogeneous waveguide. From the above investigations, it is found that in the ring-loaded corrugated horn, the useful bandwidth is 1.35 times broader than that in the conventional corrugated horn. The theoretical results are verified by the experimental results. 相似文献
20.
《Microwave Theory and Techniques》1987,35(12):1156-1160
A precise design is presented for a bandpass filter constructed by placing TE/sub 01delta/ dielectric ring resonators coaxially in a TE/sub 01/ cutoff circular waveguide. On the basis of a rigorous analysis by the mode- matching technique, the interresonator coupling coefficients are determined accurately from the calculation of two resonant frequencies f/sub sh/ and f/sub op/ when the structurally symmetric plane is short- and open-circuited. For the TE/sub 01delta/ ring resonator,the resonant frequency f/sub 0/, the temperature coefficient tau/sub f/, the unloaded Q(Q/sub u/), and the other resonances are also calculated accurately in a similar way. From the calculations, the optimum dimensions are determined to obtain the maximum Q/sub u/, as F/sub r/ = f/sub r/ /f/sub 0/ is kept constant, where f/sub r/ is the next higher resonant frequency the ring resonator using low-loss ceramics (epsilon/sub r/ = 24.3, tan delta = 5 x 10/sup -5/) has Q/sub u/ = 16800 at 12 GHz and tau/sub f/ = 0.1+-0.5 ppm/° C, while the rod one has Q/sub u/ = 14700. A four-stage Chebyshev filter having ripple of 0.04 dB and equiripple bandwidth of 27.3 MHz at f/sub 0/ =11.958 GHz is fabricated using these resonator; the measured frequency responses agree well with theory. The insertion loss is 0.9 dB, which corresponds to Q/sub u/ = 9800. 相似文献