摘要:

AbstractResins such as epoxy have been used to form a gas‐tight dam in communication cables. However, they have disadvantages due to the volume shrinkage during the curing period and thermal expansion. This causes reliability problems such as the breakage at the contact surface. Thus when resins are used in the optical fiber, the influence of their properties on the gas‐tightness and optical loss must be well understood. This paper discusses the influence of the strain caused by the curing process of the resins on the optical loss and air‐tightness. In addition, the structural design of a resin gas‐tight dam is described. First, the influence of the strain caused by the resin on the strain in the optical fiber will be described and the design condition of the use of the resin to minimize the optical loss will be shown. Next, the design condition for air‐tightness is discussed by obtaining the relationship between the hardness of the resin and gas‐tightness, the method of experimentally obtaining the strain distribution in the strain at various temperatures during the curing process, and the application of the gas‐tight dam for an optical fiber cable. From these results, a gas‐tight dam with two layers of resin for strain absorbing to protect the optical fiber is designed. As a result of the evaluation of the properties of the designed structure, we decided that it is applicable to the optical fiber cable from the point of air‐tightness and optical lo

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701201

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractLarge KDP crystals having a high damage threshold against laser light are required for harmonic generation of a 1.053 μm high‐power glass laser system for nuclear fusion experiment. We studied the internal damage threshold of KDP crystals at 1.053 μm, 1‐ns pulsewidth.For the crystals grown by the temperature falling method, the damage thresholds of 8.3, 7.3, 6.1, and 11.2 J/cm2were obtained for the KDP samples having a laser irradiated surface cut perpedicular to the (010) direction ([010] sample), parallel to the (101) surface ((101) sample), type I cut (type I sample), and type II cut (type II sample) of phase matching angle. The sample cut from the prismatic sector showed an anomalously large value of threshold 34 J/cm2.For the crystals grown by the electro‐dialysis method, 3.3, 5.0, 5.9, and 6.9 J/cm2were obtained for “[010],” “(101),” “type 1,” and “type II

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe have derived the relationship between the leakage inductance and the winding structure for an electronic transformer with a flat cable wound around a circular cross‐sectional core. It is found that: (1) the leakage inductance of a flat cable transformer with a circular cross‐sectional core is approximately identical to one with a square core cross‐sectional core. Next, the winding configuration of a multilayer winding flat cable transformer is classified into lap winding, turn‐up lap winding and twisted lap winding; (2) the leakage inductance is higher for the lap winding and the turn‐up lap winding than for the one layer winding, but the increase of the equivalent capacitance is minimal for the lap winding; (3) the leakage inductance is even smaller in the twisted lap winding than in the one layer winding; and (4) the leakage inductance per winding length does not increase in the flat cable transformer even if insulators are inserted between layers.Further, based on the leakage coefficient, the unit leakage constant is defined. It is found that: (5) the circular cross‐section core is superior to the square cross‐sectional core for a wider relative bandwidth and a restricted range of unit leakage constant; and (6) a wider relative bandwidth is more difficult to obtain as the core becomes smaller. These results agree well with experime

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThis paper will describe a method for broadening the bandwidth of gain controllable monolithic amplifier circuits for the purpose of the application to the repeater circuits in the Gb/s optical transmission systems. The gain controllable differential amplifier circuit exhibits narrower bandwidth because of larger parasitic capacitance components in comparison with basic differential amplifier circuits due to the complicated circuit configuration to control the gain. Also, when the peaking method for broadening the bandwidth is applied, the peaking amounts exceed the optimum value and becomes unstable in the low‐gain operation even if the peaking amounts are optimized for the high‐gain operations. In this paper, a new gain controllable amplifier circuit using the bias current dependency of differential resistance of diodes is proposed. Furthermore, the circuit is fabricated by using the Si Bipolar Super Self‐Aligned process Technology (SST). A broadband characteristic of 1.6 GHz bandwidth and 29‐dB gain controllable width has been obtained. These are sufficient for the application to the Gb/s optical repeater c

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA nondestructive method to determine the parameter of the DSA transistor by capacitance measurement is proposed. Determined parameters are the gate oxide thickness (dOX), the drain impurity density (ND), the drain area (SD), the drain flat‐band voltage (VFB), and the lateral profile along the channel which is one of the features of the DSA MOS transistor.In this method, both depletion and inversion characteristics of gate‐drain capacitance (CGD) are analyzed mainly by fitting them to the measured characteristics.A nonplanar DSA MOS (V‐MOS) transistor is used as a sample to apply this method and the error factors caused by a few assumptions in the analysis are disc

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractIn the high‐temperature process of semiconductors, the temperature distribution on the wafer surface during the procedures of the wafer insertion into and removal from the oxidation or diffusion furnace is important in determining the density of the dislocation due to the thermal stress and the uniformities of both the oxide thickness and the diffusion depth. As the size of a wafer and the density of integration increase, the analysis of the thermal transient characteristics becomes more important.This paper analyzes the model of the temperature transient characteristics proposed previously and describes the transient characteristics on a wafer by measuring the temperature distribution en a wafer in a furnace using an infrared radiometer.The simulation for a case where a wafer of 150 mm in diameter is inserted into a furnace at a speed of 20 cm/min indicates that the temperature variation on a wafer at every moment is as high as 150°C. This result agrees with the experimental result within an accuracy of 25°C. When the insertion speed is 100 cm/min, the temperature variation increases by 20 to 30 percent and is maintained until the wafer reaches the high‐temperature zone. This is caused by the increase in the rate of temperature change with time due to the radiation from the tube wall which is the external heat source. This tendency is more noticeable for waters located at the middl

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractMethods of improvement on a planar‐circuit‐type 3‐dB hybrid consisting of a four‐port circular disk‐shaped resonator are proposed and described. The characteristics of a conventional circular disk hybrid are degraded gradually by higher‐order modes of the disk resonator as the ratio of the disk radius to the port width decreases, i.e., as the center frequency becomes higher. This is caused mainly by the fact that the ports arrangement is based only upon the field distribution of the fundamental (1, 1) resonant mode (dipole mode). It is important in practice to prevent the deterioration of the hybrid characteristics because of the suitability of the hybrid for application at relatively high microwave frequencies. This is due to simplicity of its structure, and a small value of the ratio is desired for broadening the bandwidth. From the foregoing viewpoint, the purpose of this paper is to improve the hybrid characteristics without loss of simplicity. Great improvement is obtained by rearrangement of the four ports upon consideration of the higher‐order resonant modes and/or addition of a capacitive stub at the circumference of the resonator. Furthermore, the bandwidth of the hybrid is broadened considerably by adding an impedance step between the resonator and each 50‐Ω coupling port. These improvements also are confirme

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA comprehensive design for high‐power DFB lasers is discussed. An anti‐reflection/high‐reflection facet structure and optimized coupling between forward and backward propagation waves in continuous corrugation‐type devices are shown in to be essential for this purpose. By applying the forementioned optimization to 1.5 μm DFB laser parameters, a maximum output power of 45 mW and a quantum efficiency of 37 percent are obtained at 20°C. The devices oscillate in a single‐longitudinal‐mode with a side‐mode suppression ratio of more than 30 dB under 1 GHz sinuso

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe argon pressure dependence of saturation magnetizationMSand film composition in TbCo and TbFe sputtered films under the substrate biasVB× 0 was investigated. It was found that the change in the shape of multitarget surfaces influencesMSstrongly. When the sputtering period was 60 min, the Ar pressure dependence ofMSand the film composition were different in TbCo and TbFe films. This was found to be due to the existence of the composition gradient in the direction of the film thickness in the TbFe film deposited under high Ar pressure. As a result of investigating the multitarget surfaces, the Tb chip surface was found to be contaminated by TM atoms (Co, Fe) and the intermetallic compound was formed. On the other hand, the TM target surface was clean. The surface condition of the Tb chip was different in the Tb ‐ Co and Tb ‐ Fe multitargets. The Tb surface of the Tb ‐ Fe target was covered with cone‐shaped projections, causing the composition gradient in the film thickness direction when the Ar pressure was high. When the sputtering period was short (shorter than 12 min), the composition ratio againstNTM/NTb) againstMSand Tb decreases with the increase of Ar pressure in both depositions of TbCo and Tb

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThis paper describes the newly developed Tri‐Pole Magnetron Sputtering System, which has the third magnetic pole of an electric magnet, or the control pole, in addition to the conventionalNandSpoles between them. The system can switch the polarity of the control pole through the direction of the coil current so that it can shift the target‐eroded region by the magnetic field configuration. Therefore, film composition can easily be controlled by an appropriate composite target of coaxial disks corresponding to magnetic field configuration, at the same time changing the duty ratio of the current flowing through the control‐pole coil to adjust the sputtering time of each target‐component. The system is superior in both controllability and stability because of its static operation without mechanical moving elements. The switching behavior of the sputtered region is clarified via the target erosion pattern. Then the applicability of the system to the composition control of lead titanate films, etc., is di

ISSN:8756-663X    

DOI:10.1002/ecjb.4420701210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY