我们用有机小分子材料NPB和Alq3以交替生长的方法,制备了双层和多层周期结构的样品。通过吸收光谱和光致发光谱的表征,尽管NPB的光致发光峰和Alq3的吸收峰重叠比较小,结果显示,多层周期性结构有利于二者之间的能量传递。这说明,周期性多层结构降低了层与层之间的距离,使得NPB可以有效地将能量传递给Alq3,从而增强Alq3的发光。因此,该多层周期性结构有潜力应用在有机电致发光器件中,来提高器件的性能。

The structure and operation principle of asymmetric gate commutated thyristor were described.On the basic of 3 kV asymmetric gate controlled thyristor model,the Ⅰ-Ⅴ characteristic of GCT in forward direction were analyzed by using MEDICI simulator.Considering on-state characteristics and blocking characteristics,the optimal design parameters for p base region of 3 kV asymmetric GCT were obtained.

高温火腿肠蒸煮后表面水分残留始终得不到生产企业的有效解决。在对产品工艺及规范了解的基础上,首次提出并设计了全自动加工线。在传送带上利用高压热风将产品水分带走.控制系统采用PLC及变频器。加工线集成了自控、中央空调及机械传输等相关技术。生产线经过对各品种的实际运行,达到了设计要求。它在食品加工中有着广泛的应用前景。

Direct current glow discharge has been employed to prepare the SIPOS passivation films on the beveled power semiconductor devices.Results obtained indicates that the performance of power semiconductor devices passivated by SIPOS are improved,and SIPOS based process is effective and expected to enhance the reliability of device.Based on this,the SIPOS/PI passivation structure is proposed to improve the characteristic of the surface of beveled power semiconductor device.

With the continuous development of CMOS technology into the deep submicron stage,the effective channel length of device is less than 0.25 um,highly integrated device has enhanced integrated circuit(IC) performance and computational speed and lower per chip the manufacturing costs.However,with the reduced size of the device,there have been some reliability problems.ESD(electrostatic discharge) is one of the most important problems of the MOS Integrated Circuits in the reliability.ESD main causes the electronic device damage the following:in the semiconductor,the media has broken down,as the result of oxide film rupture;because EOS(electrical overstress) cause overheating,resulting in melting metal wire;the parasitic PNPN structure leads to CMOS device lock;ESD causes hidden defective in the structure of the device,and they did not immediately invalidated,but it causes the failures and intermittent long-term reliability issues,such damage is very weak and difficult to find,so it is potential damage.IC industry from losses caused by ESD is a very serious problem.

This paper introduced a design of the low volltage large current switching powersupply,it took the PWM control chip UC3825 as the core.It expounded the design scheme of the main circuit and control circuit topology structure of main circuit design,and designed a soft start-up and overcomepaction over-current protection circuit,application feedback method and pulse width modulation techniques to realize the stable output voltage,current,and developed a 15 V/1 200 A prototype.

This paper designed a RS-485 interface chip which is high efficiency of communication,reliable of use.It can be safely used in industrial occasions to ensure that the communication between computers and industrial products is fluent.This chip was fully consistent with RS-485 communication protocol.It used a single 5 V power supply and could be fabricated in 0.6 μm BCD process.This chip was mainly composed of a driver and a receiver.The driver slew rates is not limited and could transmit up to 2.5 Mbps.The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.

The design of the buffer layer in asymmetrical gate commutated thyristor was advanced by analyzing its characteristics.According to the design, the structural model of the GCT is established,and the characteristics of the buffer layer are simutated by using MEDICI software.The results show that the introduction of a buffer layer structure of the GCT can adjust blocking characteristic and on-state characteristic well,and optimize the integrated characteristic of GCT.