The Effect of Temperature on the Development of a Contrast HSQ Electronic Resist

Russian Microelectronics - A study was made of the dependence of the contrast value of a negative electron resist based on hydrogen-silsesquioxane (HSQ) in the process of the development of...     

Ultra-dense hydrogen silsesquioxane (HSQ) structures on thin silicon nitride membranes

Ultra-dense nanometer-scale gratings (20 nm pitch) on thin silicon nitride (Si₃N₄) membrane substrates using hydrogen silsesquioxane (HSQ) resist have been fabricated. Scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) were performed to evaluate the pattern quality of the HSQ gratings. The results are compared with HSQ gratings fabricated on silicon substrates.     

Dependence of the Resistance of the Negative e-Beam Resist HSQ Versus the Dose in the RIE and Wet Etching Processes

This article studied the resistance of the negative electron resist based on hydrogen-silsesquioxane (HSQ) depending on the dose of exposure in the process of Reactive Ion Etching (RIE). These studies showed the strong dependence of resistance on irradiation dose (in case of full development of the e-beam resist) even after annealing the resist 30 minutes 400°C in air. Selectivity up to 14 was obtained in the process of reactive ion etching of silicon in a mixture of gases SF₆: C₄F₈. These results can be used to manufacturing of silicon nanoscale structures. It was shown that the resistance to wet etching in a 5% solution of hydrofluoric acid (HF) is also determined by irradiation dose. Additionally, taking into account the obtained results, silicon nanowires of width 10 nm with an aspect ratio of 1: 10 was manufactured.     

Tensile strain ultra thin body SiGe on insulator through hetero-layer transfer technique

The ultra thin body (UTB) SiGe on insulator (SGOI) substrate with body thickness of only 5 nm has been fabricated by hetero-layer transfer technique with highly selective wet etching. According to Raman spectroscopy, UTB-SiGe layer with Ge fraction of 67% and +1% partially tensile strain was transferred onto the SiO₂/Si host substrate without the strain degradation. To present the feasibility of UTB-SGOI substrate, a well-behaved performance of 2-μm-gate-length normally off UTB-SGOI nMOSFET has also been demonstrated.     

Reliability of ultra thin ZrO2 films on strained-Si

Ultra thin high-k zirconium oxide (equivalent oxide thickness 1.57 nm) films have been deposited on strained-Si/relaxed-Si_0.8Ge_0.2 heterolayers using zirconium tetra-tert-butoxide (ZTB) as an organometallic source at low temperature (<200 °C) by plasma enhanced chemical vapour deposition (PECVD) technique in a microwave (700 W, 2.45 GHz) plasma cavity discharge system at a pressure of 66.67 Pa. The trapping/detrapping behavior of charge carriers in ultra thin ZrO₂ gate dielectric during constant current (CCS) and voltage stressing (CVS) has been investigated. Stress induced leakage current (SILC) through ZrO₂ is modeled by taking into account the inelastic trap-assisted tunneling (ITAT) mechanism via traps located below the conduction band of ZrO₂ layer. Trap generation rate and trap cross-section are extracted. A capture cross-section in the range of 10⁻¹⁹ cm² as compared to 10⁻¹⁶ cm² in SiO₂ has been observed. The trapping charge density, Q_ot and charge centroid, X_t are also empirically modeled. The time dependence of defect density variation is calculated within the dispersive transport model, assuming that these defects are produced during random hopping transport of positively charge species in the insulating layer. Dielectric breakdown and reliability of the dielectric films have been studied using constant voltage stressing. A high time-dependent dielectric breakdown (TDDB, t_bd > 1500 s) is observed under high constant voltage stress.     

含氟紫外纳米压印光刻胶的研制

从主体树脂性质、光引发剂的选择、助剂的选择、溶剂的设计等多个方面论述了含氟纳米压印光刻胶的研制工艺。在纯有机材料为主体的光刻胶中引入了全氟丙烯酸酯助剂,解释了含氟助剂在光刻胶中的作用。使用接触角法评估了全氟丙烯酸酯对光刻胶表面性质的影响,并通过接触角数据预测了光刻胶的脱模能力。通过旋涂、压印、刻蚀等实验验证了光刻胶的性能,并通过实验数据筛选出了最佳配方。研制出的光刻胶样品图形保真度高、分辨率好,对底材有良好的黏附力,且具有良好的脱模能力。     

光学薄膜膜厚监控方法及其进展

针对目前膜厚监控技术的广泛使用和其方法的日益多样性 ,力图对光学薄膜膜厚监控方法作一个全面、细致的描述。包括膜厚监控方法的分类、进展和展望 ,重点介绍了几种膜厚的光学监控方法     

光学膜厚监控方法

光学膜厚监控方法是光学镀膜过程中用以控制光学薄膜光学厚度的主要方法,也是实现镀膜自动化的关键技术之一.了解光学膜厚监控方法的工作原理、特点及误差来源,有助于在实际应用中根据所镀产品的要求选择合适的光学监控方法及监控参数.文中针对最常用的两种光学膜厚监控方法一单波长法和宽光谱法,分别介绍其工作原理,给出了单波长下根据薄膜的透射率或反射率推算膜层厚度的计算方法以及宽光谱法所常用的3种评价函数,总结出影响单波长法测量的8种因素和宽光谱法的11种因素,并根据这些因素分析了这两种方法的特点和适用范围.     

High density packaging technology ultra thin package & new tab package

As electronic devices become more highly integrated, the demand for small, high pin count packages has been increasing. We have developed two new types of IC packages in response to this demand. One is an ultra thin small outline package (TSOP) which has been reduced in size from the standard SOP and the other, which uses Tape Automated Bonding (TAB) technology, is a super thin, high pin count TAB in cap (T.I.C.) package. In this paper, we present these packages and their features along with the technologies used to improve package reliability and TAB. Thin packages are vulnerable to high humidity exposure, especially after heat shock.1 The following items were therefore investigated in order to improve humidity resistance: (1) The molding compound thermal stress, (2) Water absorption into the molding compound and its effect on package cracking during solder dipping, (3) Chip attach pad area and its affect on package cracking, (4) Adhesion between molding resin and chip attach pad and its affect on humidity resistance. With the improvements made as a result of these investigations, the reliability of the new thin packages is similar to that of the standard thicker plastic packages.     

Photo-CVD process for ultra thin SiO2 films

In this paper we first report the use of very low deposition rate photo-induced chemical vapor deposition process, (below 0.05 nm/min). This photo-CVD process is adequate to grow very thin and ultra thin layers of SiO₂. Details on the design of the reaction chamber, reactive gases and process parameters to obtain the desired deposition regime are presented. Dependence of deposition rate on pressure in the chamber and gas flow ratio is discussed. Deposited layers were characterized using I–V and C–V techniques.     

超薄金属膜V-型槽等离子波导的定向耦合研究

分析了在 1 550 nm 波长下超薄金属膜(金膜厚t=10 nm)V-型槽等离子波导间长程沟道等离激元导模的定向耦合。通过计算不同波导间距下的模式分布,得出了定向耦合器中奇、偶模有效折射率实部和传播长度随波导间距的变化情况,并进一步计算了相邻波导间的耦合长度、最大串扰与波导间距的关系曲线。计算结果表明:在波导间距较小时,耦合长度小于各模式的传播长度,随着波导间距的增加,耦合长度随之增加,最大串扰随之减小。对超薄金属膜V-型槽等离子波导的定向耦研究在集成光路的实际应用中具有重要的价值。     

Planarization properties of hydrogen silsesquioxane (HSQ) influence on CMP

Low dielectric constant materials are now required as intermetallic dielectrics to reduce RC delay in advanced technologies. Hydrogen silsesquioxane (HSQ) is a spin-on dielectric with a dielectric constant around 3. Local planarization of HSQ and its impact on the global planarization due to CMP process was studied. Local planarization of HSQ and its impact on the global planarization due to CMP process was studied. When lines and spaces are equal, HSQ shows a good planarization for lines smaller than 20 μm. In this case, the HSQ thickness on metal line is equal to 2500 Å, which is the minimum which can be obtained for this metal thickness and HSQ deposited. For various environments of the metal line HSQ planarizes better for small lines in a dense zone created by an array of lines or plates of metal. For the CMP process the planarization is good for small lines, as for HSQ but in an array of lines only. Plates must be totally prohibited for CMP process. Finally, for an intermetal dielectric including HSQ the goal of CMP is no more a local planarization as for gap fill but a large scale intra-die planarization.     

单镜头激光三角法薄板厚度测量研究

为了精确测量薄板类材料的厚度,分析了双光路激光三角法测厚原理,建立了一种单镜头激光三角法厚度测量系统.该系统以半导体激光器为光源,配以单镜头成像系统、图像采集与数据处理系统.描述了系统的检测原理、检测方法和实验装置,讨论了激光器光束轴心线与成像透镜光轴夹角与系统分辨率的关系,并基于最小二乘法拟合得出了光斑距离与被测物厚度的函数关系式,最后通过标定实验对系统精度进行了实验论证.结果表明,该系统消除了双光路激光三角法上下测量系统难以同步的问题,分辨率高,精度控制在10m,良好地满足了工业测量的需求.     

厚度对TaN薄膜电性能的影响研究

采用直流反应磁控溅射法制备了TaN薄膜,研究了薄膜厚度对TaN薄膜微观结构及电性能的影响。结果表明,薄膜厚度对TaN薄膜的表面形貌和相结构都没有影响,但会显著影响TaN薄膜的电学性能。在87~424 nm的范围内,随着薄膜厚度的增大,所制TaN薄膜的电阻率从555×10–6.cm减小到285×10–6.cm,方阻从84/□减小到9/□,电阻温度系数(TCR)从–120×10–6/℃增加到+50×10–6/℃。可以通过调节薄膜的厚度调节TaN薄膜的电阻率和TCR。     

Measurement of thin liquid film thickness in pipes based on optical interferometry

Accurate measurement of the thin liquid film thickness in pipes is the foundation for studying the characteristics of the film. In this paper, an interferometry-based measurement of liquid film thickness in transparent pipes is developed, which can greatly improve the accuracy, extend the lower limit of measurement and provide a new technical approach for the calibration and traceability. The light intensity distribution is established based on the optical path analysis and a mathematical model....     

Electrical property dependence on thickness and morphology of nanocrystalline diamond thin films

In this study, we investigate the influence of nanocrystalline diamond (NCD) thin film morphology and thickness on their electrical properties. NCD films are grown on p-type Si substrates with varied thicknesses from 250 to 788 nm. Electrical contacts are formed from combination of Ti/Au metal layers (100 nm thick each). The I-V and breakdown field measurements are used to analyze the electrical properties of metal/NCD/Si sandwich structure. In addition, NCD films are analyzed by scanning electron microscopy and Raman spectroscopy for better interpretation of the I-V measurements.     

A CV technique for measuring thin SOI film thickness

A technique is developed to measure silicon-on-insulator (SOI) silicon device film thickness using a MOSFET. The method is based on CV measurements between gate and source/drain at two different back-gate voltages. The SOI devices used in this study were n⁺ polysilicon gate n-channel MOSFETs fabricated with modified submicrometer CMOS technology on SIMOX (separation by implanted oxygen) wafers. The SIMOX wafers were implanted with a high dose of oxygen ions (10¹⁸ cm^-2) at 200 keV and subsequently annealed at 1230°C. The NMOS threshold boron implant dose is 2×10¹² cm^-2. This method is simple, nondestructive, and no special test structure is needed. Using this technique, SOI film thickness mapping was made on a finished wafer and a thickness variation of ±150 Å was found     

Laser-assisted patterning of solution-processed oxide semiconductor thin film using a metal absorption layer

We present a method to pattern solution-processed oxide semiconductor thin films by all laser process. A metal thin film is first photoetched by a spatially-modulated pulsed Nd-YAG laser beam and this layer is then covered with a semiconductor film. Uniform irradiation by the same laser generates a thermo-elastic force on the underlying metal layer and this force serves to detach it from the substrate, leaving only a patterned semiconductor structure. Sharp-edged zinc-tin oxide (ZTO) patterns at the micrometer scales could be fabricated over a few square centimeters by a single pulse of 850 mJ. A mobility of 7.6 × 10⁻² cm² V⁻¹ s⁻¹, an on/off ratio higher than 10⁶, and an off-current of 1.91 × 10⁻¹¹ A were achieved from a thin film transistor (TFT) with the patterned ZTO channel. These values were similar to those from a reference TFT, demonstrating the feasibility of this patterning process for electronic devices.