挠性印制板化学镀镍工艺研究

通过正交试验优化了镀镍的工艺条件，确定了化学镀镍的工艺条件的工作范围。提出了温度和镍层厚度的线性方程。实验的结果表明，在已确定的工艺条件范围内，能获得符合生产要求的镍金镀层。     

用于优化集成电路制造工艺条件的正交试验方法

本文采用正交试验方法，在原有设备和技术不变的条件下，用很少的试验次数，优化出一种汽车专用ＩＣ生产的最佳工艺条件；并找到了器件参数随工艺条件的变化规律，使该电路在大批量生产过程中，降低成本，提高了经济效益。该方法也可用于半导体新品ＩＣ试制工艺条件的优化。     

BOX-COX变换与微电路工艺设备表征

(利用部分要因试验设计与数据转换表征微电路工艺设备)。因为试验数据的尺度效应和测量的固有属性,试验数据常违反模型误差的正态和一致性假设。通过BOX-COX数据转换分析,确定热氧化工艺目标值的最优转换形式,针对转换后数据建立的回归模型满足上述假设。结果表明:数据转换的建模方法能满足方差分析的假设(违反度减轻),并且能更多发掘数据信息,氧化膜厚的模型拟合修正判定系数R2由93.54%增加到98.64%。所得模型用于优化工艺条件,在满足膜厚目标下,非均匀性由0.2%减小到0.08%。文中讨论的基于数据转换的建模方法可以用于半导体制造其他工艺。     

利用分步试验设计表征/优化工艺空间均匀性

半导体制造工艺成品率对空间差异越来越敏感,需要表征与优化工艺空间均匀性.利用两步试验设计方法,针对六输入变量的热氧化工艺,仅需31次试验,便建立了表征工艺目标和空间均匀性响应曲面模型.利用该模型优化工艺,得到了满足其他工艺指标下工艺空间均匀性最优的工艺设置.片间非均匀性从1.44%减小到0.77%,片内非均匀性从0.2%减小到0.12%.     

基于DOE的微组装工艺过程的统计表征与优化

随着微组装工艺技术和设备的发展,许多先进工艺涉及多个输入参数和输出响应,而且参数间具有不同程度交互作用,使得传统的以经验为主的试误法或一次改变一个参数的试验方法并不能满足这些先进工艺的要求。利用实验设计技术,通过建立关键工艺参数与输出响应之间的统计模型,实现了对微组装中金丝球形键合工艺过程的统计表征。试验结果表明,该模型的预测值与实测值吻合较好,可进一步用于工艺过程的设计与参数优化。     

1～3μm短波红外光导探测器阳极氧化工艺的研究

简要介绍了通过阳极氧化工艺条件的改变，确定1～3μm短波红外光导探测器阳极氧化的最佳工艺条件，从而改善了器件性能，大大提高了产品成品率。     

氧化工艺对玻璃—金属封接管壳气密性的影响

进行了氧化工艺试验，分析了可伐预氧化质量对玻封金属管壳气密性的影响，提出了改进可伐预氧化工艺的途径。     

超薄氧化层制备及其可靠性研究

文章简述了超薄氧化层SiO2,的击穿机理,采用了恒定电流法表征超薄氧化层TDDB效应,并研究了清洗方法,氧化温度,氧化方式等工艺因素对超薄氧化层的可靠性影响.实验表明,在850℃、900℃等高温条件下,可通过干氧N/O分压的方法制备厚度4nm~5nm、均一性小于2.0%超薄氧化层;RCA清洗工艺过程中,APM中的NH3...     

快速氧化生长超薄硅氧化层的变入射角椭圆偏振研究

采用多角度椭圆偏振光谱测量，并结合一定的数值计算方法，首次同时精确测出了多种工艺条件下由快速热氧化法生长的超薄氧化层厚度与折射率，对该方法生长的氧化层厚度与氧化时间平方根的关系进行了研究并计算了氧化生长速率的温度激活能，同时也对薄氧化层折射率与氧化层厚度的关系进行了探讨．     

链式氧化制备SiO2膜的研究

研究了应用链式扩散设备对经过制绒、清洗、扩散和刻蚀处理后的单晶P型硅片进行热氧化SiO2膜的生长。采用准稳态光电导衰减法(QSSPC)在室温条件下对氧化前后硅片的少子寿命进行测试,探讨了氧化工艺条件对少子寿命、SiO2薄膜质量的影响机理,并对氧化工艺进行了优化。实验结果表明:在氧气流量为20L/min,带速为13i/m,氧化工艺区阶梯式温度设置为600、800、800、800、800、800、850和900℃时,链式氧化后硅片少子寿命达到42.5μs,SiO2膜的厚度适合,结构致密;在不影响减反效果的情况下,获得了良好的钝化效果。     

Modeling of the silicon (100) thermal oxidation: from quantum to macroscopic formulation

In this paper, we investigate the modeling of dry silicon thermal oxidation in the light of the model capabilities and the trends in microelectronics. We show how a combined use of different models can be made in a way to generate process simulations that are strongly related to microscopic physical phenomena. In conjunction with experimental literature data, first principle calculations have been carried out with the objective of isolating some elementary oxidation mechanisms, i.e. basic atomic movements and their corresponding activation energies. This preliminary list of mechanisms is discussed in detail. A growth mechanism allowing the oxide defect generation is proposed. We then present Monte Carlo calculations with the implemented mechanisms where at least three silicon layers are oxidized. Finally, we introduce a macroscopic formulation of these mechanisms via the Chemical Rate Theory.     

Calibration of a two-dimensional numerical model for theoptimization of LOGOS-type isolations by response surface methodology

The models used for process simulation have to be carefully calibrated in order to insure a correct prediction of the topography and doping/stress profiles of microelectronic devices. With the current miniaturization of these devices, the requirements on the accuracy of the simulated results become greater, which puts more constraints on the calibration methodology. This is particularly the case for the silicon oxidation model, which is involved in numerous fundamental steps of an industrial process. In this paper, using response surface methodology, a viscoelastic oxidation model has been calibrated on a wide range of process conditions, which has allowed the optimization of LOCOS-type isolation structures for a 0.35-μm CMOS technology     

热氧化方法制备直径可控的有序硅纳米线阵列

采用金属辅助化学刻蚀方法结合纳米球模板技术制备出了有序硅纳米线阵列.硅纳米线阵列经过高温热氧化形成一定厚度的氧化层,再使用稀释的HF溶液去除表面氧化层得到可控直径/周期比、低孔隙密度的有序纳米线阵列.主要研究了氧化温度、氧化时间对硅纳米线形貌的影响,并根据扩展的Deal-Grove模型计算了硅纳米线氧化层厚度与氧化时间的关系,讨论了氧化过程中应力分布的影响,理论计算结果与实验结果一致.最后,采用两步氧化的方法制备出了低直径/周期比(约0.1)、低孔隙密度的有序硅纳米线阵列.     

快速热生长二氧化硅-硅结构负偏压温度不稳定性

研究了快速热生长二氧化硅MOS结构的负偏压温度不稳定性。这种MOS结构在未经受过金属化后热处理时有室温负偏压不稳定性,但热处理后,其负偏压温度不稳定性就比电阻炉中热生长二氧化硅MOS结构小。研究了快速热生长后在氩气中快速热处理的时间和温度、热生长后在氧气中的冷却方式、金属化后退火的温度对这种不稳定性的影响。金属化时的辐照不但引进正电荷和界面陷阱,也把负偏压温度不稳定性机构引进了MOS结构。另外还研究了负偏压温度应力后平带电压负向位移的时间演化过程,讨论了负偏压温度不稳定性的机制。     

Temperature and thickness dependence of steam oxidation of AlAs incylindrical mesa structures

The Deal-Grove model of thermal oxidation kinetics is adapted to cylindrically symmetric mesa structures and applied to study steam oxidation of AlAs. Oxidation process parameters are extracted from available experimental data as functions of temperature and the AlAs layer thickness. The oxidation rate is found to be very sensitive not only to temperature, but also to the oxidation front position inside the mesa. The oxidation rate slows down as the oxidation front moves into the mesa, reaches a minimum, and then accelerates at the final stages of the oxidation process. Complex nonmonotonic dependence of the oxidation process on layer thickness is also revealed     

Process uniformity and slip dislocation patterns in linearlyramped-temperature transient rapid thermal processing of silicon

Rapid thermal processing (RTP) of silicon using transient linearly ramped-temperature saw-toothed and triangular thermal cycles has been evaluated by characterization of the process uniformity and slip dislocation line patterns for a wide range of process parameters. Rapid thermal oxidation was chosen as the process vehicle for these studies. The process uniformity and slip dislocation line patterns are strongly affected by both the transient and steady-state segments of the thermal cycles. The strong dependencies of the process uniformity and slip dislocation lines on the thermal cycle parameters suggest that the overall performance of a RTP reactor must be specified not only under steady-state thermal conditions, but also for controlled transient thermal cycles. Transient ramped-temperature RTP cycles with medium-to-high peak process temperatures (i.e. T_max=1100°-1150°C) were found to be the optimal process conditions for growing thin gate oxides in the range of 60-120 Å with superior process uniformity and minimum slip dislocation line generation. The results of this work provide insight and useful methodology for process optimization in order to improve process uniformity, minimize generation of slip dislocation lines, and obtain good device electrical characteristics     

A process simulation model for multilayer structures involving polycrystalline silicon

The increasing complexity of VLSI fabrication often requires the use of multilayer structures above the silicon substrate. Electrical and metallurgical properties of multilayer structures have an important effect on circuit performance and reliability. Although process simulation models are available and widely used for computer-aided process design, none of the existing process simulation programs have the capability for modeling multilayer structures. A new model with such capability has been developed and this paper presents the physics as well as the results of simulation supported by experimental data. The model can simulate many desirable properties of multilayer structures involving polycrystalline silicon, such as grain growth, resistivity and oxidation rate of the polysilicon layer, the impurity redistribution across multilayers after high-temperature thermal processing, impurity segregation both at grain boundaries and at interfaces, and the interdependent phenomena of dopant-dependent oxidation/diffusion.     

SiG高温氧化的研究

热氧化是碳化硅晶片工艺中一种常用的工艺,但基于硅工艺的氧化温度一般都相对较低,此温度下,碳化硅氧化缓慢,在很多情况下很难满足工艺需求.利用新设计的高温氧化设备对碳化硅晶片进行不同温度下的氧化实验.实验结果显示,高温下,碳化硅氧化速度加快,温度的增加对氧化速度影响极大,以1 200℃时的氧化速率为基准,1 250℃时的氧化速率是1 200℃时的1.5倍;1 300℃下的氧化速率能达到1 200℃的2倍;而在1 350 ℃时,氧化速度已经将近1 200 ℃时的3倍.     

Phosphomolybdic acid-assisted thermal oxidation of GaAs

An experimental investigation is conducted into the thermal oxidation of GaAs assisted by phosphomolybdic acid. The mechanism of the process is identified. It is established that oxide films thus produced consist mainly of GaPO₄ and are superior in insulating performance to ones made by conventional thermal oxidation.