表面处理对HfO_2栅介质MOS电容界面特性的影响

在溅射淀积HfO2栅介质之前,采用NO、N2O、O2+CHCCl3(TCE)进行表面预处理。结果表明,预处理能改善界面和近界面特性,减小界面层厚度,尤其是新颖的TCE+少量O2的表面处理工艺,能有效抑制界面层的生长,大大降低界面态密度,减小栅极漏电流。其机理在于TCE分解产生的Cl2和HCl能有效地钝化界面附近Si悬挂键和其它结构缺陷,并能去除离子污染。     

HfTiO高k栅介质Ge MOS电容的制备及特性分析

采用反应磁控溅射方法和湿氮退火工艺在Ge衬底上分别制备了HfO2和HfTiO高介电常数(k)栅介质薄膜。电特性测量表明,HfTiO样品由于Ti元素的引入有效提高了栅介质的介电常数,减小了等效氧化物厚度,但同时也使界面态密度有所增加。控制HfTiO中Ti的含量及表面预处理工艺有望改善HfTiO/Ge界面质量。     

CCD栅介质工艺对多晶硅层间介质的影响

CCD多晶硅交叠区域绝缘介质对成品率和器件可靠性具有重要的影响.采用扫描电子显微镜和电学测试系统研究了CCD栅介质工艺对多晶硅层间介质的影响.研究结果表明:栅介质工艺对多晶硅层间介质形貌具有显著的影响.栅介质氮化硅淀积后进行氧化,随着氧化时间延长,靠近栅介质氮化硅区域的多晶硅层间介质层厚度增大.增加氮化硅氧化时间到320 min,多晶硅层间薄弱区氧化层厚度增加到227 nm.在前一次多晶硅氧化后淀积一层15 nm厚氮化硅,能够很好地填充多晶硅层间介质空隙区,不会对CCD工作电压产生不利的影响.     

一种新型的6H-SiC MOS器件栅介质制备工艺

采用干 O2 +CHCCl3(TCE)氧化并进干 /湿 NO退火工艺生长 6H-Si C MOS器件栅介质 ,研究了 Si O2 /Si C界面特性。结果表明 ,NO退火进一步降低了 Si O2 /Si C的界面态密度和边界陷阱密度 ,减小了高场应力下平带电压漂移 ,增强了器件可靠性 ,尤其是湿 NO退火的效果更为明显。     

超薄SiO2栅介质厚度提取与分析

在分析半经典模型和量子模型的基础上,得到包括量子效应和多晶硅耗尽效应的栅氧厚度提取模型.栅介质厚度模拟结果和椭偏仪所测实验结果吻合良好.     

超薄SiO_2栅介质厚度提取与分析

在分析半经典模型和量子模型的基础上,得到包括量子效应和多晶硅耗尽效应的栅氧厚度提取模型.栅介质厚度模拟结果和椭偏仪所测实验结果吻合良好.     

施主型界面态引起深亚微米槽栅PMOS特性的退化

基于流体动力学能量输运模型 ,对沟道杂质浓度不同的槽栅和平面 PMOSFET中施主型界面态引起的器件特性的退化进行了研究 ,并与受主型界面态的影响进行了对比 .研究结果表明同样浓度的界面态在槽栅器件中引起的器件特性的漂移远大于平面器件 ,且 N型施主界面态密度对器件特性的影响远大于 P型界面态 ,N型施主界面态引起器件特性的退化趋势与 P型受主界面态相似 ,而 P型施主界面态则与 N型受主界面态相似 .沟道杂质浓度不同 ,界面态引起的器件特性的退化则不同     

施主型界面态引起槽栅PMOSFET性能退化的特征

基于流体动力学能量输运模型 ,对沟道杂质浓度不同的深亚微米槽栅和平面 PMOSFET中施主型界面态引起的器件特性的退化进行了研究 .研究结果表明同样浓度的界面态密度在槽栅器件中引起的器件特性的漂移远大于平面器件 ,且电子施主界面态密度对器件特性的影响远大于空穴界面态 .特别是沟道杂质浓度不同 ,界面态引起的器件特性的退化不同 .沟道掺杂浓度提高 ,同样的界面态密度造成的漏极特性漂移增大 .     

Theoretical Reflection Coefficient of Metal Grid Reflectors at a Dielectric Interface

Reflection properties of square apertures metal mesh mirrors are studied theoretically with the Finite-Difference Time-Domain (FDTD) method associated to Floquet Boundary Conditions. The reflector is illuminated by a normally incident plane wave and is located at an interface between two semi infinite low loss dielectric materials. Reflectivity and phase of the reflection coefficient are given in the non diffraction region for a wide range of square apertures, and for the four situations corresponding to an interface between free space and fused quartz.     

The Impedance of a Wire Grid Parallel to a Dielectric Interface

Analysis is given for the problem of reflection of a plane wave at oblique incidence on a wire grid which is parallel to a plane interface between two homogeneous dielectrics. It is assumed that the wire grid is a periodic structure and consists of thin cylindrical wires of homogeneous material. The equivalent circuit is derived where it is shown that the space on either side of the interface can by a transmission line, and the grid itself is represented by a pure shunt element across one of the lines.     

基于CCD技术的玻璃测厚系统

针对传统厚度测量方法的弊端,研究了利用半导体激光和线阵电荷耦合元件(CCD)组成的在600 ℃高温条件下的一套非接触式、在线玻璃厚度检测系统.利用几何光学中光的反射和折射原理对玻璃进行非接触测量,选用TCD1501C线阵CCD作为图像传感器,设计了CCD视频信号处理电路.玻璃厚度测量的精度能达到0.01 mm(测量范围在2～20 mm).     

不同类型层压机对PCB涨缩和介厚均匀性的影响

随着PCB技术的迅猛发展,其层数不断增加,内层芯板厚度越来越薄,这对制造过程中涨缩和介厚均匀性的控制提出了更高的要求.由于B系统和C系统两种层压机加热和加压方式的不同,使用不同的材料对这两种层压机试验板的涨缩均匀性和介厚均匀性进行了评估.结果表明,用C系统层压机生产的试验板的尺寸变化比B的小(特别是在长边方向)并且均匀性更好;用两种层压机生产的试验板介厚的极差和标准偏差非常接近,其介厚的差距不大.     

干燥工艺对微波复合介质基板性能的影响

该文采用聚四氟乙烯(PTFE)树脂为基体,熔融SiO_2作为填料,通过机械混合、压延成型、热压烧结工艺制备出高频高速电路用微波复合介质基板,重点研究了采用不同干燥工艺对复合物结构、微波介电性能的影响。实验表明,采用旋转蒸干工艺对复合物进行处理时,可在较短的时间内去除有机物质,并能使无机填料与聚合物分散均匀。经热压烧结后,所得基板相对介电常数为2.92~2.94,损耗因子为1.3×10~(-3)。     

Effect of Silicon Thickness on Contact-Etch-Stop-Layer-Induced Silicon/Buried-Oxide Interface Stress for Partially Depleted SOI

In this letter, based on both experimental investigations and simulation confirmation, it was found that a strained contact etch stop layer over the thin silicon layer of a partially depleted silicon-on-insulator (PD-SOI) will induce high stress on the buried-oxide/silicon interface. Additionally, the interface stress increases with decrease of silicon thickness T_SI, thus enhancing the current of the MOSFET, e.g., as T_SI shrinks from 90 to 50 nm, current enhancement for PD-SOI n-channel MOS increased from 7% to 12% due to the increase of interface stress. The results are expected to be more significant for devices with thinner T_SI such as fully depleted silicon-on-insulator and multigate devices     

过渡层和界面电荷对金属硅化物/硅肖特基接触特性的影响

针对金属硅化物／硅接触存在过渡层，提出了分析这种结构的肖特基接触特性的模型；讨论了过渡层厚度、界面电行及有关参数的影响，分析了不同退火条件下PtSi／Si肖特基二极管的特性。     

CCD信号采集系统的USB接口设计

为解决针对每一个CCD象素的高速采集和实时计算机处理的问题，提出一种利用通用串行总线(USB)技术对CCD信号的每一个象素进行高速采集的方法。本文着重介绍了利用USB技术实现图像采集系统和计算机进行通信的软硬件设计方案。     

PTFE基复合介质表面金属化的研究

采用真空蒸发、溅射和化学镀铜的方法分别对研制的ＰＴＦＥ基复合介质进行了金属化处理。试验结果表明：经萘钠溶液处理后的介质，镀铜后铜层致密光亮，且剥离强度明显高于物理方法金属化的剥离强度。     

Control of Interface Traps in HfO2 Gate Dielectric on Silicon

The effects of postdeposition annealing (PDA) on the interface between HfO₂ high-k dielectric and bulk silicon were studied in detail. The key challenges of successfully adopting the high-k dielectric/Si gate stack into advanced complementary metal–oxide–semiconductor (CMOS) technology are mostly due to interfacial properties. We have proposed a PDA treatment at 600°C for several different durations (5 min to 25 min) in nitrogen or oxygen (95% N₂ + 5% O₂) ambient with a 5-nm-thick HfO₂ film on a silicon substrate. We found that oxidation of the HfO₂/Si interface, removal of the deep trap centers, and crystallization of the film take place during the postdeposition annealing (PDA). The optimal PDA conditions for low interface trap density were found to be dependent on the PDA duration. The formation of an amorphous interface layer (IL) at the HfO₂/Si interface was observed. The growth was due to oxygen incorporated during thermal annealing that reacts with the Si substrate. The interface traps of the bonding features, defect states, and hysteresis under different PDA conditions were studied using x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), transmission electron microscopy (TEM), and leakage current density–voltage (J–V) and capacitance–voltage (C–V) techniques. The results showed that the HfO₂/Si stack with PDA in oxygen showed better physical and electrical performance than with PDA in nitrogen. Therefore, PDA can improve the interface properties of HfO₂/Si and the densification of HfO₂ thin films.