3200V双p阱终端VDMOS击穿特性仿真研究

基于场限环终端技术理论,提出了一种具有双p阱结构的垂直双扩散金属氧化物半导体场效应晶体管(VDMOS)。通过数值模拟软件分别仿真了p阱各项参数和漂移区掺杂浓度与击穿电压的关系,提取器件击穿时的表面电场并分析其击穿机理。研究结果表明,当漂移区掺杂浓度一定时,击穿电压随p阱数量和结深的增大而增大,随p阱掺杂浓度的增大而先增大后减小;当p阱参数一定时,击穿电压随漂移区掺杂浓度的增大而先增大后减小。经优化器件各项参数,击穿电压(V_B)达到3 200 V,与传统平面栅型VDMOS相比提升了305%,终端有效长度仅为26μm,表面电场最大值为1.21×10⁶ V/cm,且分布相对均匀,终端稳定性和可靠性高。     

Surface Growth of Boron Nitride Nanotubes through Boron Source Design

Boron nitride nanotubes (BNNTs) are promising materials due to their unique physical and chemical properties. Fabrication technologies based on gas-phase reactions reduce the control and collection efficiency of BNNTs due to reactant and product dispersion within the reaction vessel. A surface growth method that allows for controllable growth of BNNTs in certain regions using a preburied boron source is introduced. This work leverages the high solubility of boron in metals to create a boronized layer on the surface which serves as the boron source to confine the growth of BNNTs. Dense and uniform BNNTs are obtained after loading catalysts onto the boronized substrate and annealing under ammonia. Confirmatory experiments demonstrate that the boride layer provides boron for BNNTs growth. Furthermore, the patterned growth of BNNTs is realized by patterning the boronizing region, demonstrating the controllability of this method. In addition, the Ni substrate with BNNTs growth exhibits better performance in corrosion resistance and thermal conductivity than pure Ni. This study introduces an alternative strategy for the surface growth of BNNTs based on boron source design, which offers new possibilities for the controllable preparation of BNNTs for various applications.     

无VOC免清洗助焊剂焊后残留物的可靠性评价

为了研究焊后残留物的腐蚀性以及可能对PCB的电气绝缘性能造成的影响,通过表面绝缘电阻(Rs)试验和电化学迁移试验评价了三种不同固体含量的无VOC(挥发性有机物)免清洗助焊剂焊后残留物的可靠性。结果表明,使用w(固体含量)为3.6%的助焊剂,湿热试验后试件的Rs大幅下降,并且PCB表面腐蚀严重;而w(固体含量)为2.3%的助焊剂,则试件具有较高的Rs(6.4×109Ω),并且对PCB腐蚀性小。使用放大30倍的显微镜观察电化学迁移测试后的试件,均没有发现枝晶。     

集成波导型表面等离子体共振传感芯片及其理论分析

集成波导型表面等离子体共振传感芯片是表面等离子体共振传感技术和微电子制造技术相结合的产物.介绍了集成表面等离子体共振传感芯片的工作机理和基本结构,并通过基于传统波导模式的分析法结合表面等离子体波的色散方程,发展出简单实用的波导表面等离子体共振分析方法.利用该方法对波导型表面等离子体共振传感芯片的工作状态进行了理论建模,给出了各特性参数之间的关系.这证明该方法是分析等离子体共振传感芯片优化的有力工具.     

Electronic characterization of heterojunctions by surface potential monitoring

An original approach for studying the formation of semiconductor heterojunctions and their electronic properties is discussed and illustrated. Monitoring the changes in the surface potential during the heterojunction formation lends itself to direct measurement of the band discontinuities, Debye length, and the width of the space-charge region at heterojunction interfaces. The contribution of an interface dipole is considered. The technique is demonstrated by a technologically significant experimental example.     

一种可展宽频带的微带贴片天线

提出了一种可展宽频带的微带贴片天线。通过对普通矩形微带贴片天线进行切角而展宽频带。由贴片天线的谐振频率和该贴片上的电流分布出发,研究了产生宽带特性的机理。采用基于有限元算法的高频电磁场仿真软件ANSOFTHFSS对该天线的电特性进行计算,结果表明：该天线的阻抗带宽（S11〈-10dB）达到16％（370MHz）。证明了该方法的有效性。     

胶体硒化镉量子点的荧光时间分辨谱研究

使用化学胶体法合成了12个高质量、不同尺寸的胶体硒化镉量子点.测量了样品的时间分辨光致发光谱、TEM谱,同时测量并计算了样品的光致发光量子产率以及光致发光寿命.研究结果表明:硒化镉量子点的光辐射强度与表面相关的光辐射强度均由量子点的表面缺陷形式决定,并且也决定了光致发光量子产率、光致发光寿命.量子点的表面缺陷形式决定于尺寸,在量子点的生长过程中存在的表面的优化/重构也依赖于尺寸.     

W-Mo合金表面超精密加工的CMP技术研究

阐述了金属化学机械抛光的机理。将半导体制造工艺中的nm级平坦化技术、化学机械抛光技术拓展并应用到W-Mo合金工艺中,在实现精密物理材料表面高平坦度、低粗糙度的前提下,提高W-Mo合金去除速率。采用碱性抛光液进行实验,确定了抛光液的成分;分析了W-Mo合金化学机械抛光中压力、流量、转速、pH值、活性剂等参数对W-Mo合金的影响。实验表明,实现W-Mo合金表面超精密抛光的最佳条件为:压力0.06MPa,流速160mL/min,转速60r/min,pH值10.1~10.3。     

基于拓扑法的分离面检测和可视化

分析与时间相关二维矢量场可视化的拓扑法,并针对分离面检测过程中,流面积分的不连续以及映射的离散,进行改进.首先运用Sobel算子检测种子曲线,然后对检测到的种子曲线进行积分,从而检测到分离面.实验结果显示该方法对分离面的检测更加快速、精确.