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1.
Induced absorption was observed in an InP:Fe crystal under nanosecond pulse illumination at 1.06-μm wavelength. The maximum induced absorption was 0.05 cm-1 when probed at a 1.06-μm wavelength and 0.30 cm-1 when probed at a 1.30-μm wavelength. The kinetics are studied together with the photocurrent giving the recombination times of holes (100 ns) at room temperature and an estimate for that of electrons (0.5 ns). The induced absorption is attributed to a population redistribution of the different iron impurity states. Computer simulations are able to explain all the features found in the experiments and give values for the photoionization cross sections, in particular for the unknown cross section Fe2+*→Fe3++e - 相似文献
2.
Parrillo L.C. Pfiester J.R. Lin J.-H. Travis E.O. Sivan R.D. Gunderson C.D. 《Electron Devices, IEEE Transactions on》1991,38(1):39-46
An advanced 0.5-μm CMOS disposable lightly doped drain (LDD) spacer technology has been developed. This 0.5-μm CMOS technology features surface-channel LDD NMOS and PMOS devices, n+/p+ poly gates, 125-A-thick gate oxide, and Ti-salicided source/drain/gate regions. Using only two masking steps, the NMOS and PMOS LDD spacers are defined separately to provide deep arsenic n+ regions for lower salicided junction leakage, while simultaneously providing shallow phosphorus n- and boron p- regions for improved device short-channel effects. Additionally, the process allows independent adjustment of the LDD and salicide spacers to optimize the LDD design while avoiding salicide bridging of source/drain to gate regions. The results indicate extrapolated DC hot-carrier lifetimes in excess of 10 years for a 0.3-μm electrical channel-length NMOS device operated at a power-supply voltage of 3.3 V 相似文献
3.
The carrier-induced index change was measured using a novel injection-reflection technique in combination with differential carrier lifetime data. The observed relation between index change and injected carrier density at bandgap wavelength is nonlinear and is approximately given by δn act=-6.1×10-14 ( N )0.66 for a 1.5-μm laser and δn act=-1.3×10-14 (N )0.68 for a 1.3-μm laser. The carrier-induced index change for a 1.3-μm laser at 1.53-μm wavelength is smaller and is given by δn act=-9.2×10-16 (N )0.72 相似文献
4.
A buried-channel p-MOSFET with a large-tile-angle implanted punchthrough stopper (LATIPS) is described. In this device the n+ LATIPS region was successfully realized adjacent to the p+ source/drain, even without a sidewall spacer, by taking advantage of the n+ large-tilt-angle implant. In spite of the relatively deep p+ junction of 0.2-μm depth and the low n-well concentration of 1×1016 cm-3, the 0.5-μm LATIPS device (with corresponding channel length of 0.3 μm) achieved high punchthrough resistance, e.g. a low subthreshold swing of 95 mV/decade with a high transconductance of 135 mS/mm 相似文献
5.
Meng Z. Kamebayashi J. Higashihata M. Nakata Y. Okada T. Kubota Y. Nishimura N. Teshima T. 《Photonics Technology Letters, IEEE》2002,14(5):609-611
Fiber laser operating property at 1.55-μm band in a newly developed Ce,Er:ZBLAN fiber by a continuous-wave laser diode pumping at 980 nm is presented. The output characteristics of the Ce,Er:ZBLAN fiber laser system are analyzed in detail based on the rate equations model by taking into account the energy transfer between Ce3+ and Er 3+ ions, as well as the upconversion mechanisms. The promotion role of the Ce in the erbium-doped ZBLAN for the 1.55-μm band fiber laser operation has been realized 相似文献
6.
An 0.8-μm n-channel MOSFET with a TiSi2-Si Schottky clamped drain-to-body junction (SCDR) and an n+ implanted standard source structure have been fabricated in a conventional 0.8-μm salicide CMOS process without any process modifications. The SCDR should be useful for reducing susceptibility for latch-up in integrated CMOS RF power amplifiers and switches where drain to p-substrate junctions can be forward biased during normal operations. Output I-V characteristics of the devices are the same as those of conventional MOSFETs, while parasitic lateral n+-drain/p-substrate/n+-source bipolar transistor measurements showed significantly reduced current gains because the Schottky barrier diode which does not inject minority carriers (electrons) to the p-substrate base clamps the n+ drain-to-p-substrate guard-ring diode connected in parallel 相似文献
7.
Mogami T. Wakabayashi H. Saito Y. Tatsumi T. Matsuki T. Kunio T. 《Electron Devices, IEEE Transactions on》1996,43(6):932-939
A low-resistance self-aligned Ti-silicide process featuring selective silicon deposition and subsequent pre-amorphization (SEDAM) is proposed and characterized for sub-quarter micron CMOS devices. 0.15-μm CMOS devices with low-resistance and uniform TiSi2 on gate and source/drain regions were fabricated using the SEDAM process. Non-doped silicon films were selectively deposited on gate and source/drain regions to reduce suppression of silicidation due to heavily-doped As in the silicon. Silicidation was also enhanced by pre-amorphization, using ion-implantation, on the narrow gate and source/drain regions. Low-resistance and uniform TiSi2 films were achieved on all narrow, long n+ and p+ poly-Si and diffusion layers of 0.15-μm CMOS devices. TiSi2 films with a sheet resistance of 5 to 7 Ω/sq were stably and uniformly formed on 0.15-μm-wide n+ and p+ poly-Si. No degradation in leakage characteristics was observed in pn-junctions with TiSi2 films. It was confirmed that, using SEDAM, excellent device characteristics were achieved for 0.15-μm NMOSFET's and PMOSFET's with self-aligned TiSi2 films 相似文献
8.
It is shown that the absorption loss coefficient of the active layer for 1.48-μm bulk lasers is 66 cm-1 which is between 45 and 107 cm-1 for 1.3-μm bulk lasers and for 1.55-μm bulk lasers, respectively. It is also described that the absorption loss coefficient of the active layer for 1.48-μm multiple-quantum-well (MQW) lasers is 28 cm-1 which is about two-fifths of that for 1.48-μm bulk lasers. Therefore, the high slope efficiency of the 1.48-μm MQW lasers is attributed not only to the small optical confinement factor but also to the small absorption loss coefficient of the active layer 相似文献
9.
p+-n junction diodes for sub-0.25-μm CMOS circuits were fabricated using focused ion beam (FIB) Ga implantation into n-Si (100) substrates with background doping of Nb=(5-10)×10 15 and Nb+=(1-10)×1017 cm-3. Implant energy was varied from 2 to 50 keV at doses ranging from 1×1013 to 1×1015 cm-2 with different scan speeds. Rapid thermal annealing (RTA) was performed at either 600 °C or 700°C for 30 s. Diodes fabricated on Nb+ with 10-keV Ga+ exhibited a leakage current (IR) 100× smaller than those fabricated with 50-keV Ga+. Tunneling was determined to be the major current transport mechanism for the diodes fabricated on Nb+ substrates. An optimal condition for I R on Nb+ substrates was obtained at 15 keV/1×1015 cm-2. Diodes annealed at 600°C were found to have an I R 1000× smaller than those annealed at 700°C. I -V characteristics of diodes fabricated on Nb substrates with low-energy Ga+ showed no implant energy dependence. I -V characteristics were also measured as a function of temperature from 25 to 200°C. For diodes implanted with 15-keV Ga +, the cross-over temperatures between I diff and I g-r occurred at 106°C for Nb + and at 91°C for Nb substrates 相似文献
10.
Noda M. Hosogi K. Oku T. Nishitani K. Otsubo M. 《Electron Devices, IEEE Transactions on》1992,39(4):757-766
The authors present formation conditions for ion-implanted regions of a GaAs buried p-layer lightly doped drain (BPLDD) MESFET that can improve short-channel effect, V th uniformity, and FET operating speed, simultaneously. For 0.7-μm gates, a Mg+ dose of 2×1012 cm-2 at 300 keV and a Si+ dose of 2×1012 cm-2 at 50 keV are suitable for the p layer and n' layer, respectively. A σV th of 7 mV is realized. Gate-edge capacitance of the 0.7-μm-gate BPLDD that consists of both overlap capacitance and fringing capacitance is successfully reduced to 0.5 fF/μm, which is about 50% of that of a non-LDD buried p-layer (BP) FET. Another parasitic capacitance due to the p-layer was found to have less effect on the speed than the gate-edge one. Consequently, the gate propagation delay time of the BPLDD can be reduced to 15 ps at power dissipation of 1 mW/gate, which is about 65% of that of a BP. Applying the 0.7-μm-gate BPLDD to 16-kb SRAMs, the authors have obtained a maximum access time of less than 5 ns with a galloping test pattern 相似文献
11.
Iwatsuki K. Nishi S. Saruwatari M. Nakagawa K. 《Photonics Technology Letters, IEEE》1990,2(7):507-509
Optical soliton transmission of 5 Gb/s over a 23-km amplification spacing using a gain-switched 1.55-μm distributed feedback laser diode and Ti:LiNbO3 intensity modulator is discussed. An Er +-doped fiber amplifier, pumped by 1.45- and 1.48-μm laser diodes, is employed for achieving intense optical pulses. Transmission fiber-loss is completely compensated for by Raman amplification using by 1.45- and 1.48-μm laser-diode pumping. A bit error rate (BER) of 2×10-10 has been obtained 相似文献
12.
Ghezzo M. Brown D.M. Downey E. Kretchmer J. Hennessy W. Polla D.L. Bakhru H. 《Electron Device Letters, IEEE》1992,13(12):639-641
6H-SiC diodes fabricated using high-temperature nitrogen implantation up to 1000°C are reported. Diodes were formed by RIE etching a 0.8-μm-deep mesa across the N+/P junction using NF3/O2 with an aluminum transfer mask. The junction was passivated with a deposited SiO2 layer 0.6 μm thick. Contacts were made to N+ and P regions with thin nickel and aluminum layers, respectively, followed by a short anneal between 900 and 1000°C. These diodes have reverse-bias leakage at 25°C as low as 5×10-11 A/cm2 at 10 V 相似文献
13.
In0.08Ga0.92As MESFETs were grown in GaAs (100) substrates by molecular beam epitaxy (MBE). The structure comprised an undoped compositionally graded InxGa1-x As buffer layer, an In0.08Ga0.92As active layer, and an n+-In0.08Ga0.92As cap layer. FETs with 50-μm width and 0.4-μm gate length were fabricated using the standard processing technique. The best device showed a maximum current density of 700 mA/mm and a transconductance of 400 mS/mm. The transconductance is extremely high for the doping level used and is comparable to that of a 0.25-μm gate GaAs MESFET with an active layer doped to 1018 cm-3. The current-gain cutoff frequency was 36 GHz and the power-gain cutoff frequency was 65 GHz. The current gain cutoff frequency is comparable to that of a 0.25-μm gate GaAs MESFET 相似文献
14.
Denker B.I. Kertesz I. Kirjanov A.V. Kroo N. Maljutin A.A. Osiko V.V. Sverchkov S.E. Sverchkov U.E. 《Quantum Electronics, IEEE Journal of》1989,25(9):1979-1980
The possibility of obtaining high laser output energies at a 1.32-μm wavelength using thin LiNdLa phosphate glass slabs with a high Nd3+ concentration is discussed. In the experiments, 3×14×125-mm slabs were prepared from LiNdLa phosphate glass with a Nd-concentration of 1.2×1021 cm-3. The facets of the slabs were not antireflection-coated. They were tested in a silver-coated quartz tube reflector of 25-mm diameter and pumped by 450-μs pulses from a flash lamp with a 120-mm arc length. In this construction the light, which passes through the slab, returns to it after reflection from the tube surface. Most of the radiation falls on the wider side of the slab at large angles of incidence, thus maximizing its path inside the slab. The quartz reflector was water cooled. The 150-mm laser resonator was formed by two flat mirrors. At 1.32-μm lasing wavelength an output mirror of r =95% reflectivity was used with less than 10% reflectivity at 1.32 μm 相似文献
15.
The gain degradation of erbium-doped fiber amplifiers (EDFAs) with high erbium ion (Er3+) concentration at 1.48- and 0.98-μm pump wavelengths is modeled by introducing inhomogeneous cooperative up-conversion (IhCU). General formulas describing the gain degradation as a function of IhCU rate are obtained by solving rate equations for population probabilities in the relevant Er3+ energy levels. The experimental results, such as low gain for high Er3+ concentration, and higher saturated gain with counterpropagation than with copropagation pumping, which have not yet been explained theoretically, are qualitatively explained by this model. Good agreement between the measured and calculated gain is obtained. The gain degradation characteristics at 1.48- and 0.98-μm pump wavelengths are analyzed with this model. The advantage of counterpropagation pumping is determined qualitatively. The noise figure degradation is also evaluated 相似文献
16.
Yamada M. Shimizu M. Takeshita T. Okayasu M. Horiguchi M. Uehara S. Sugita E. 《Photonics Technology Letters, IEEE》1989,1(12):422-424
The performance of an Er3+-doped fiber amplifier pumped by 0.98 μm InGaAs laser diodes (LDs) is reported. By using a fiber with low Er3+ content and optimizing the fiber length, a maximum signal gain of 37.8 dB at 30-mW pump power was realized at a signal wavelength of 1.536 μm. A maximum gain coefficient of 1.9 dB/mW at 14 mW pump power was achieved. It was found that the fiber amplifier pumped by the 0.98-μm LDs is twice as efficient as that pumped by 1.48-μm LDs, from the viewpoint of both required fiber length and the attained gain 相似文献
17.
Zhang X. Lahoz F. Serrano C. Lacoste G. Daran E. 《Quantum Electronics, IEEE Journal of》2000,36(2):243-247
The 1.3-μm emission of Nd3+-doped LaF3 thin films grown on LaF3 and CaF2 (111) substrates by molecular beam epitaxy is reported. The waveguide behavior of the heteroepitaxial layers has been demonstrated and the refractive indexes measured. Guided spectra have been obtained from these layers using a prism-coupling technique. The 1.3-μm emission corresponding to the 4F 3/2→4I3/2 transition has been characterized as a function of Nd3+ concentration and temperature. The relative efficiencies of different excitation bands were compared. The optimum concentration for Nd3+ dopant has been found to be about 1 at.%. A narrowing of the emission lines is observed in the homoepitaxial layers compared to the heteroepitaxial layers. The decay of the luminescence of the 4F3/2 level measured at room temperature is similar for homoepitaxial and heteroepitaxial layers 相似文献
18.
Qiuxia Xu He Qian Huaxiang Yin Lin Jia Honghao Ji Baoqing Chen Yajiang Zhu Min Liu Zhensheng Han Huanzhang Hu Yulin Qiu Dexin Wu 《Electron Devices, IEEE Transactions on》2001,48(7):1412-1420
The fabrication of sub-0.1-μm CMOS devices and ring oscillator circuits has been successfully explored. The key technologies include: lateral local super-steep-retrograde (SSR) channel doping with heavy ion implantation, 40-nm ultrashallow source/drain (S/D) extension, 3-nm nitrided gate oxide, dual p+/n+ poly-Si gate electrode, double sidewall scheme, e-beam lithography and RIE etching for sub-0.1-μm poly-Si gate pattern, thin and low sheet resistance SALICIDE process, etc. By these innovations in the technologies, high-performance sub-0.1-μm CMOS devices with excellent short-channel effects (SCEs) and good driving ability have been fabricated successfully; the shortest channel length is 70 nm. 57 stage unloaded 0.1-μm CMOS ring oscillator circuits exhibiting delay 23.8 ps/stage at 1.5 V, and 17.5 ps/stage and 12.5 ps/stage at 2 V and 3 V, respectively, are achieved 相似文献
19.
A generalized model for 3-μm (4I 11/2 →4I 13/2)Er lasers is proposed. The essential energy transfer processes present in the single-doped Er 3+ systems (up-conversion from 4I 13/2, up-conversion from 4 I 11/2, cross-relaxation from 4S 3/2), as well as those present in Cr3+ codoped Er 3+ systems, are taken into account. In the frame of this model, the main features of 3 μm Er3+ lasers, such as long pulse or CW operation, the change of emission wavelength as a function of pumping conditions, and the effects of codoping with Ho3+ or Tm3+ ions, are explained 相似文献
20.
Onodera K. Tokumitsu M. Tomizawa M. Asai K. 《Electron Devices, IEEE Transactions on》1991,38(3):429-436
Fully ion-implanted n+ self-aligned GaAs MESFETs with Au/WSiN refractory metal gates have been fabricated by adopting neutral buried p-layers formed by 50-keV Be-implantation. S-parameter measurements and equivalent circuit fittings are discussed. When the Be dose is increased from 2×1012 cm-2 to 4×1012 cm-2, the maximum value of the cutoff frequency with a 0.2-μm gate falls off from 108 to 78 GHz. This is because a neutral buried player makes the intrinsic gate-source capacitance increase markedly, while its influence on gate-drain capacitance and gate-source fringing capacitance is negligible. The maximum oscillation frequency recovers, however, due primarily to the drain conductance suppression by the higher-concentration buried p-layer. An equivalent value of over 130 GHz has been obtained for both 0.2-μm-gate GaAs MESFETs 相似文献