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1986 Vol. 8, No. 3
Display Method:
1986, 8(3): 161-168.
Abstract:
A new kind of high Q (quality factor) analogue inductor (L=50 H, Q=98.8) and lowloss (loss resistance Re may approach zero, i.e, Q) capacity multiplier composed of complementary composite follower using field effect and dipolar transistors is proposed.As compared with the analogue inductor and capacity multiplier composed of integrated operational amplifier, the new device has the following features: its circuit is simple, with only one set of supply, more suitable for low frequency large inductor and capacity multiplier, and has complementary temperature characteristics. The working principle of this kind of analogue inductor and capacity multiplier is analysed and the relations between Q and , Q and r (complementary resistance), Re and r are estabilshed. The design of this kind of device is also discussed and verified experimentally, Besides, the expression for the sensitivity of the Q value of the analogue inductor is derived.
A new kind of high Q (quality factor) analogue inductor (L=50 H, Q=98.8) and lowloss (loss resistance Re may approach zero, i.e, Q) capacity multiplier composed of complementary composite follower using field effect and dipolar transistors is proposed.As compared with the analogue inductor and capacity multiplier composed of integrated operational amplifier, the new device has the following features: its circuit is simple, with only one set of supply, more suitable for low frequency large inductor and capacity multiplier, and has complementary temperature characteristics. The working principle of this kind of analogue inductor and capacity multiplier is analysed and the relations between Q and , Q and r (complementary resistance), Re and r are estabilshed. The design of this kind of device is also discussed and verified experimentally, Besides, the expression for the sensitivity of the Q value of the analogue inductor is derived.
1986, 8(3): 169-179.
Abstract:
An algorithm for circuit yield estimation and optimization is described. To obtain the first and second derivatives of yield with respect to center and get the optimal circuit center, the Monte Carlo analysis and Newton method are employed. By using fail samples and rearranging sample frequencies according to their weights, two new methods for improving estimation and reducing computation are presented. Both theoretical analysis and calculation examples show that this algorithm performs well and can be used for middle-scale circuit design. No matter the region of acceptability is convex set or not, the algorithm is available.
An algorithm for circuit yield estimation and optimization is described. To obtain the first and second derivatives of yield with respect to center and get the optimal circuit center, the Monte Carlo analysis and Newton method are employed. By using fail samples and rearranging sample frequencies according to their weights, two new methods for improving estimation and reducing computation are presented. Both theoretical analysis and calculation examples show that this algorithm performs well and can be used for middle-scale circuit design. No matter the region of acceptability is convex set or not, the algorithm is available.
1986, 8(3): 180-187.
Abstract:
Based on the work on reflector antenna with circularly projected aperture accomplished by E. Mittra and others (1979), this paper extends the Jacobi-Bessel series method in analysis of reflector antenna to the area where far-field of paraboloid reflector with elliptically projected aperture can be evaluated by using the unique recurrence relatio ns of modified Jacobi polynomials. Meanwhile, a new kind of partial recurrence relations of the series expasion coefficients pBmn is deduced so that whole CPU time for numerical integration can be saved about three times.
Based on the work on reflector antenna with circularly projected aperture accomplished by E. Mittra and others (1979), this paper extends the Jacobi-Bessel series method in analysis of reflector antenna to the area where far-field of paraboloid reflector with elliptically projected aperture can be evaluated by using the unique recurrence relatio ns of modified Jacobi polynomials. Meanwhile, a new kind of partial recurrence relations of the series expasion coefficients pBmn is deduced so that whole CPU time for numerical integration can be saved about three times.
1986, 8(3): 188-195.
Abstract:
A universal form of the M and N vector wave f unctions and its normalized integration constants for the regular boundary condition in Cartesian, cylindrical and spherical coordinates are given, and then the eorresponding dyadic Green s functions are obtained.
A universal form of the M and N vector wave f unctions and its normalized integration constants for the regular boundary condition in Cartesian, cylindrical and spherical coordinates are given, and then the eorresponding dyadic Green s functions are obtained.
1986, 8(3): 196-203.
Abstract:
This is the second part of our work on DGF at the source region in circular waveguides. With the application of the main results of the first part, a systematic investigation on the general properties of DGF at the source region is given. The dyadic version of the boundary conditions for Maxwall s equations is derived and the completeness of the expanision of the transverse current in circular waveguides in terms of the vector M and N is proved. It is shown that the electric and magnetic DGF satisfy the satisfy the basic dyadic equations.
This is the second part of our work on DGF at the source region in circular waveguides. With the application of the main results of the first part, a systematic investigation on the general properties of DGF at the source region is given. The dyadic version of the boundary conditions for Maxwall s equations is derived and the completeness of the expanision of the transverse current in circular waveguides in terms of the vector M and N is proved. It is shown that the electric and magnetic DGF satisfy the satisfy the basic dyadic equations.
1986, 8(3): 204-208.
Abstract:
In this paper, a new calculation method of multienergy implantation i.e., eqivalent area method has been proposed. According to the requirement for designing the specific device, a variety of concentration and implantation energy profile which can be arbitrarily supposed may be obtained by this method. Hence, it is possible to make the thin layer device which has a plane concentration profile.Using this method, the Si-EAPD device which has a rectangular on low-high-low concentration profile and the GaAs-MESFET or Si-IMPATT device which has a horsehead shape concentration profile have been designed and calculated. The calculated results are very satisfying. The prospect of the use of designing new-type device is predicted. The calculated results in this paper coicide with the experimental ones given by R.H.Benhard(1977).
In this paper, a new calculation method of multienergy implantation i.e., eqivalent area method has been proposed. According to the requirement for designing the specific device, a variety of concentration and implantation energy profile which can be arbitrarily supposed may be obtained by this method. Hence, it is possible to make the thin layer device which has a plane concentration profile.Using this method, the Si-EAPD device which has a rectangular on low-high-low concentration profile and the GaAs-MESFET or Si-IMPATT device which has a horsehead shape concentration profile have been designed and calculated. The calculated results are very satisfying. The prospect of the use of designing new-type device is predicted. The calculated results in this paper coicide with the experimental ones given by R.H.Benhard(1977).
1986, 8(3): 209-216.
Abstract:
In this paper, a Monte Carlo simulation of the energy dissipation profiles of 30, 50 and 100 keV incident beams in this film (0.4 m) electon resist, polymethyl methacrylate (PMMA), on thick silicon substrate in electron beam lithography is preaented. The radial scattering and energy loss of incident electrons (including backscattered electrons from the substrate) are simulated under illumination of ideal point source and Ganssiah round beam spot source, and the histories of 30000-50000 electrons are computed.
In this paper, a Monte Carlo simulation of the energy dissipation profiles of 30, 50 and 100 keV incident beams in this film (0.4 m) electon resist, polymethyl methacrylate (PMMA), on thick silicon substrate in electron beam lithography is preaented. The radial scattering and energy loss of incident electrons (including backscattered electrons from the substrate) are simulated under illumination of ideal point source and Ganssiah round beam spot source, and the histories of 30000-50000 electrons are computed.
1986, 8(3): 217-222.
Abstract:
The spectra of the optical absorption conficient in the low absorption region are obtained by using a normalization procedure for the photoconductivity spectra. The results are explained in terms of optieal transitions of electrons from loealized states in exponential valence-band tail and in danglihg bond states. 1.0 eV below the conduction-band edge to extended states above the conduction-band edge. Then the density of the gap states below the Fermi energy EF is abtained. From the investigation of recombination kinetics, the average density of the gap states in the range of (EFn-EF) is obtained. Then the density of the gap states above the Fermi energy EF is obtained. It indicates that the width of the conduction-band tail is narrower than that of valence-band tail.
The spectra of the optical absorption conficient in the low absorption region are obtained by using a normalization procedure for the photoconductivity spectra. The results are explained in terms of optieal transitions of electrons from loealized states in exponential valence-band tail and in danglihg bond states. 1.0 eV below the conduction-band edge to extended states above the conduction-band edge. Then the density of the gap states below the Fermi energy EF is abtained. From the investigation of recombination kinetics, the average density of the gap states in the range of (EFn-EF) is obtained. Then the density of the gap states above the Fermi energy EF is obtained. It indicates that the width of the conduction-band tail is narrower than that of valence-band tail.
1986, 8(3): 223-227.
Abstract:
In this paper, the experimental resnlts of a high gain broadband backfire antenna are given. The antenna is designed on the fundamental theory of backfire antenna given by the author (1982). And then the theory is verified by the experiment.
In this paper, the experimental resnlts of a high gain broadband backfire antenna are given. The antenna is designed on the fundamental theory of backfire antenna given by the author (1982). And then the theory is verified by the experiment.
1986, 8(3): 228-234.
Abstract:
A PAL 2-D adaptive separating method with which the characteristies of filters can be controlled by image edge directions at local areas is proposed. The filters and control algorithm for the 4fsc sampling system are designed. This method has the advantages of multi-performences, reasonable structure and being able to be easily realized and integrated either by digrtal circuits or by analogous circuits. Some experimental results are also given.
A PAL 2-D adaptive separating method with which the characteristies of filters can be controlled by image edge directions at local areas is proposed. The filters and control algorithm for the 4fsc sampling system are designed. This method has the advantages of multi-performences, reasonable structure and being able to be easily realized and integrated either by digrtal circuits or by analogous circuits. Some experimental results are also given.
1986, 8(3): 235-240.
Abstract:
The slices of Cu-Al-Mg alloy with thickness of 0.1 mm are prepared. Some samples are respectively activated at the tempertures of 590℃ and 620℃. The seeondary emission factors () are determined. The composition of the surface and the electron binding-energy are studied by means of XPS and ABS. It is proved that the oxide layer consisting of Al2O3 and MgO can be formed naturally at room temperature. This oxide layer exhibits lower electron binding-energy, high and satisfactory stability.
The slices of Cu-Al-Mg alloy with thickness of 0.1 mm are prepared. Some samples are respectively activated at the tempertures of 590℃ and 620℃. The seeondary emission factors () are determined. The composition of the surface and the electron binding-energy are studied by means of XPS and ABS. It is proved that the oxide layer consisting of Al2O3 and MgO can be formed naturally at room temperature. This oxide layer exhibits lower electron binding-energy, high and satisfactory stability.
