直拉硅单晶中的流动图形缺陷

用Secco腐蚀液对直径15 0 mm p型(10 0 )直拉硅单晶片进行择优腐蚀后,得到了流动图形缺陷(FPDs) ,并通过原子力显微镜(AFM)对其微观结构进行观察.实验发现,在FPDs缺陷的尖端存在有几百纳米的由(111)面构成的八面体空洞,这与Takeno等人的实验结果相反,他们认为FPD的端部是间隙型的位错环;实验还发现,FPD端部的空洞随腐蚀时间延长会逐渐变为圆形的浅坑直至最后消失     

直拉硅单晶中的流动图形缺陷

用Secco腐蚀液对直径150mm p型(100)直拉硅单晶片进行择优腐蚀后,得到了流动图形缺陷(FPDs),并通过原子力显微镜(AFM)对其微观结构进行观察.实验发现,在FPDs缺陷的尖端存在有几百纳米的由(111)面构成的八面体空洞,这与Takeno等人的实验结果相反,他们认为FPD的端部是间隙型的位错环;实验还发现,FPD端部的空洞随腐蚀时间延长会逐渐变为圆形的浅坑直至最后消失.     

快速预热处理对大直径CZ-Si中FPDs及清洁区的影响

研究了不同气氛下快速预热处理(RTA)后,硅片中的流动图形缺陷(FPDs)密度和随后两步热处理形成的魔幻清洁区(MDZ)之间的关系.硅片经过高温快速预热处理后,再经过800℃(4h)+1000℃(16h)常规退火,以形成MDZ.研究发现,当硅片在Ar气氛或N2/O2(9%)混合气氛下RTA预处理后,FPDs密度较低,随后热处理出现的氧沉淀诱生缺陷密度较高、清洁区较宽.对于N2/O2混和气氛,随着O2含量的增加,FPDs和氧沉淀诱生缺陷密度变小,纯O2气氛下预处理后硅片中FPDs和氧沉淀诱生缺陷密度最低.因此,可以通过调节N2/O2混合气氛中两种气氛的比例来控制空洞型微缺陷和硅片体内氧沉淀诱生缺陷的密度.     

快速预热处理对大直径CZ-Si中FPDs及清洁区的影响

研究了不同气氛下快速预热处理(RTA)后,硅片中的流动图形缺陷(FPDs)密度和随后两步热处理形成的魔幻清洁区(MDZ)之间的关系.硅片经过高温快速预热处理后,再经过800℃(4h) 1000℃(16h)常规退火,以形成MDZ.研究发现,当硅片在Ar气氛或N2/O2(9%)混合气氛下RTA预处理后,FPDs密度较低,随后热处理出现的氧沉淀诱生缺陷密度较高、清洁区较宽.对于N2/O2混和气氛,随着O2含量的增加,FPDs和氧沉淀诱生缺陷密度变小,纯O2气氛下预处理后硅片中FPDs和氧沉淀诱生缺陷密度最低.因此,可以通过调节N2/O2混合气氛中两种气氛的比例来控制空洞型微缺陷和硅片体内氧沉淀诱生缺陷的密度.     

Ar气氛下快速退火对CZ-Si单晶中FPD的影响

将Si片经Secco腐蚀液腐蚀,用光学显微镜和原子力显微镜(AFM)对CZ-Si单晶中的流动图形缺陷(FPD)的形貌、分布及结构进行了研究,对Si片进行了湿氧化处理并采用较新的快速退火方法(RTA),在Ar气氛下对Si片进行热处理,研究了退火温度和退火时间对FPD缺陷密度的影响.结果表明,FPDs缺陷在1 100 ℃以下非常稳定;但是在1 100 ℃以上的温度,尤其在1 200℃对Si片进行RTA处理后,Si片中FPD的密度大大降低,而且随着的退火时间的延长,密度不断下降.     

氢气退火对大直径直拉硅单晶中空洞型缺陷的影响

研究了氢退火对大直径直拉硅单晶中空洞型缺陷(voids)的影响.样品在1050～1200℃范围进行氢退火,退火前后样品上的流水花样缺陷(FPD)和晶体原生粒子(COP)在腐蚀后分别用微分干涉光学显微镜和激光记数器进行观察.实验结果表明在氢退火以后,FPD缺陷的密度随温度升高不变,而样品上的COP密度大量减少.分析可知,氢气退火仅仅消除了硅片表面的voids,而对于硅片体内的voids不产生影响,并在实验的基础上,讨论了氢退火消除voids的机理.     

氢气退火对大直径直拉硅单晶中空洞型缺陷的影响

研究了氢退火对大直径直拉硅单晶中空洞型缺陷(voids)的影响.样品在1050～1200℃范围进行氢退火,退火前后样品上的流水花样缺陷(FPD)和晶体原生粒子(COP)在腐蚀后分别用微分干涉光学显微镜和激光记数器进行观察.实验结果表明在氢退火以后,FPD缺陷的密度随温度升高不变,而样品上的COP密度大量减少.分析可知,氢气退火仅仅消除了硅片表面的voids,而对于硅片体内的voids不产生影响,并在实验的基础上,讨论了氢退火消除voids的机理.     

氢气退火对大直径直拉硅单晶中空洞型缺陷的影响

研究了氢退火对大直径直拉硅单晶中空洞型缺陷 (voids)的影响 .样品在 10 5 0～ 12 0 0℃范围进行氢退火 ,退火前后样品上的流水花样缺陷 (FPD)和晶体原生粒子 (COP)在腐蚀后分别用微分干涉光学显微镜和激光记数器进行观察 .实验结果表明在氢退火以后 ,FPD缺陷的密度随温度升高不变 ,而样品上的 COP密度大量减少 .分析可知 ,氢气退火仅仅消除了硅片表面的 voids,而对于硅片体内的 voids不产生影响 ,并在实验的基础上 ,讨论了氢退火消除 voids的机理 .     

ULSI用CZ硅单晶中的空洞型原生缺陷及其控制

详细阐述了COP、LSTD和FPD等空洞型原生缺陷的基本性质、形成机理和它们与晶体生长参数的关系,以及目前主要采用的几种消除空洞型缺陷的方法.研究表明,利用快速退火消除空洞型原生缺陷,是一种简单而有效的方法.     

MLCC叠层空洞判别超声检测技术研究

通过对超声检测技术的原理进行分析,并将其与X射线检查和制样镜检技术分别进行对比,阐述了超声检测技术在检测片式多层瓷介电容器(MLCC)的裂纹、 分层和空洞等内部缺陷方面的优势.对超声显微镜的扫描原理和扫描模式进行分析,确定了MLCC内部空洞缺陷超声检测的判定方法.并利用B扫描模式对ML-CC的叠层空洞进行了判别和区分,对于提高MLCC超声检测技术检测结果的准确性具有指导意义.     

Comprehensive, in operando, and correlative investigation of defects and their impact on device performance

Despite the long history of research that has focused on the role of defects on device performance, the studies have not always been fruitful. A major reason is because these defect studies have typically been conducted in a parallel mode wherein the semiconductor wafer was divided into multiple pieces for separate optical and structural characterization, as well as device fabrication and evaluation. The major limitation of this approach was that either the defect being investigated by structural characterization techniques was not the same defect that was affecting the device performance or else the defect was not characterized under normal device operating conditions. In this review, we describe a more comprehensive approach to defect study, namely a series mode, using an array of spatially-resolved optical, electrical, and structural characterization techniques, all at the individual defect level but applied sequentially on a fabricated device. This novel sequential approach enables definitive answers to key questions, such as: (i) how do individual defects affect device performance? (ii) how does the impact depend on the device operation conditions? (iii) how does the impact vary from one defect to another? Implementation of this different approach is illustrated by the study of individual threading dislocation defects in GaAs solar cells. Additionally, we briefly describe a 3-D Raman thermometry method that can also be used for investigating the roles of defects in high power devices and device failure mechanisms.     

Low VDD and body bias conditions for testing bridge defects in the presence of process variations

Bridge defects are an important manufacturing defect that may escape test causing reliability issues. It has been shown that in nanometer regime, process variations pose important challenges for traditional delay test methods lowering test quality. Therefore, advances in test methodologies to enhance bridge detection are required. In this work a Statistical Timing Analysis Framework (STAF) is used to compute the probability of detection of bridge defects for different V_DD and RBB values. The detection of the bridge defects of a circuit is computed by the Statistical Fault Coverage (SFC). The STAF allows to capture properly the behavior of the mean and a standard circuit delay when V_DD and RBB change. Furthermore, the STAF uses a realistic bridge defect model suitable to consider appropriately the impact of V_DD and RBB on delay increase. This methodology is applied to some ISCAS benchmark circuits implemented in a commercial 65 nm CMOS technology. The obtained results of several ISCAS benchmark circuits show clearly that the Statistical Fault Coverage (SFC) increases significantly when V_DD is lowered, and increases even more when RBB is applied at Low V_DD. The test conditions to improve resistive bridge detection combining Low V_DD and Reverse Body Bias (RBB) under a delay based test are determined. It is shown that the impact of RBB on bridge detection improves significantly for a sufficient low value of V_DD. The values of Low V_DD and RBB can be selected considering the tradeoff between fault coverage and test time penalization.     

Effects of hydrogen annealing on MOS oxides

The effects of annealing MOS oxides at high temperatures in hydrogen or deuterium have been studied. Annealing at temperatures above ≈800° C causes a dramatic increase in the radiation sensitivity of the oxide. High temperature annealing also appears to cause a decrease in the dielectric strength of the oxide. Secondary ion mass spectrometry (SIMS) profiles of deuterium-annealed oxides reveal a substantial uptake of deuterium during the annealing. These results suggest that exposure of gate oxides to hydrogen at high temperatures should be avoided.     

(112)B碲锌镉衬底表面Everson腐蚀坑与材料缺陷的关系

通过研究碲锌镉衬底(112)B面缺陷腐蚀坑和(111)B面缺陷腐蚀坑之间的关系,揭示了(112)B面腐蚀坑与材料缺陷之间的关系.结果显示,Everson腐蚀剂在碲锌镉材料(112)B面上揭示的棒状腐蚀坑起源于材料中的体缺陷,或由延伸缺陷腐蚀坑在缺陷终止后演变而成,三种典型形状的锥形腐蚀坑分别来自延伸方向为<110>、<...     

基于二维光子晶体波导的1×5等比分束器

在完整的二维正方晶格硅光子晶体中引入点缺陷 和线缺陷,利用点缺陷和线缺陷 的耦合效应,提出一种基于二维光子晶体的1×5等比分束器。利用平 面波展开法和时域有 限差分法,对提 出的1×5等比分束器进行了研究。研究结果表明, 通过合理设置耦合区域 的介质柱半径,可使1.55 μm入射光实现等比传输到5个输 出端口; 为提高总透过率,在1× 5等比分束器的弯曲波导处增加散射介质柱,并对相关参数进行优化,最终实 现99.65% 的透过率,附加损耗0.015 dB。该分束器体积较小,结构简单,附加 损耗低,在未来的集成光路中具有很好的应用前景。     

LCD显示缺陷检测装备中的形状配准新方法

针对LCD显示缺陷检测的重要性以及人工检测速度慢、漏检率高的弊端,提出了一种基于图像形状匹配的LCD显示缺陷自动光学检测方法。该方法的基本原理是:待测图像与标准图像形状配准后建立缺陷模型,利用灰度平均模板与容差模板等信息,通过动态阈值分割的方法检测LCD显示缺陷。实验结果与现场应用表明:采用该方法制作的设备检测速度快,检测正确率达到98.5%,可以替代人眼检测白点、黑点、缺划等LCD显示缺陷,完全达到实际应用的要求。     

The Positive Versus Negative Effects of Defect Engineering for Solar Water Splitting: A Review

Although defect design is an essential means of improving the performance of photocatalytic materials, defect introduction is not always beneficial. Current defect engineering focuses on avoiding or modifying introduced defects to mitigate their adverse effects on solar water splitting performance. This review comprehensively summarizes the strategies for defect introduction and discusses their crucial roles in solar water splitting. Focusing on the dual effects of defects, the most basic schemes for preparing favorable defects through pretreatment and posttreatment methods are reviewed. In addition, the review focuses on strategies for overcoming or mitigating the detrimental effects of defects to improve the performance of photocatalysts. Finally, the challenges and prospects of developing a defect-based photocatalyst design strategy are outlined. This review provides a reference for preparing defect-based photocatalysts for conducting more in-depth research on defects. Additionally, it offers ideas for utilizing unfavorable defects and converting them into favorable defects for performance improvement.     

LCD点状缺陷分析与研究

LCD作为一个新兴的高科技光电产业,现已几乎全面取代CRT显示器而成为主流显示器。但是LCD生产流程复杂,生产过程中会出现各种缺陷,使得良品率下降并造成成本增加。文章通过对两种典型点状缺陷样品的实验观测,结合外推长度理论及长程扰动理论,论证了不同缺陷核心对周围液晶分子产生的不同影响。     

Origin of Surface Defects in PCB Final Finishes by the Electroless Nickel Immersion Gold Process

We suggest a unique mechanism for surface defect generation causing solder joint or bonding failures in printed circuit boards (PCBs). Surface defects can be defined as corroded holes or spikes of the Ni-P layers on the soldering or wire bonding pads of PCBs. The typical defects are the black pad or pinhole pad defects generated after final finishing by the electroless nickel immersion gold (ENIG) process. Once corroded voids or spikes are plentifully created in nickel/gold interfaces, the bonding strength of solder or wire bonding joints is reduced. Therefore, it is important to characterize the details of these surface defects. In this paper, the defect microstructures and the P content variation with the ENIG processes are investigated. The surface defect selectivity with pad size and pad connectivity is suggested based on the key findings of P content variation. An overall mechanism is proposed based on a mixed mode of concentration cell corrosion and galvanic cell corrosion. Based on these results, more reasonable root causes are suggested.     

Investigation of Mechanical Behavior of Defective Carbon Nanotubes Using Molecular Dynamics Simulation

Carbon nanotubes(CNTs) having pristine structure(i.e.,structure without any defect) hold very high mechanical properties.However,CNTs suffer from defects which can appear at production stage,purification stage or be deliberately introduced by irradiation with energetic particles or by chemical treatment.In this article,mechanical properties of single-walled nanotubes with defects are studied under both compressive and tensile loads using molecular dynamics(MD) simulations.Two types of defect-Stone-Wales and...