高分辨率的厚膜丝网印刷技术

厚膜丝网印刷是浆料润湿陶瓷基板的过程。陶瓷基板的表面张力和厚膜浆料对基板的润湿度会影响印刷线条的分辨率。文章着重研究基板的表面张力可以有效地改进丝网印刷分辨率。     

絲网印刷中的问题及解决方法

厚膜电路的制造从丝网印刷开始,丝网印刷是厚膜电路制造的最初工序,它给后面的工序带来重要影响。由于印刷不良而引起的缺陷都是在电路制成后才被发现的,所以丝网印刷     

厚膜集成电路网印应注意的技术问题

集成电路有厚膜集成电路和薄膜集成电路。厚膜集成电路通常用丝网印刷的方法制作。由于集成电路是高科技的精细产品,因此,对丝网印刷质量要求非常严格。本文主要介绍丝网印刷厚膜集成电路应注意的一些问题。     

浅谈厚膜集成电路基板印刷的质量控制

本文论述了厚膜基板生产过程中的常见问题，以及对电路的影响，分析了影响丝网印刷的因素，并简要介绍了丝网印刷的过程控制，以及常见问题的处理意见。     

丝网印刷中影响质量的因素

随着厚膜微电子技术的快速发展,在其生产过程中,丝网印刷对于整个生产的影响和作用越来越受到生产设计师和工艺师的重视。掌握和运用好丝网印刷技术,分析其中产生问题的原因,并将改进措施应用在生产实践中,不断获得更好的丝网印刷质量,是大家所期望的,本文就丝网印刷中影响质量的因素做一些探讨。     

丝网印刷与厚膜IC技术

丝网印刷与厚膜IC技术是微电子技术的核心技术之一,IC技术是指以半导体晶体材料为基础,采用专门工艺技术组成的微小型电路或系统,分别叙述了厚膜IC与网版和厚膜IC与印墨及厚膜IC等印刷技术,简单介绍了厚膜电阻的制作工艺。     

厚膜印刷模型

提出了厚膜印刷的物理模型,并用静态模型建立了丝网印刷参数和图形的压印形变量之间的关系,以解决实际印刷工艺中的图形匹配各精确套印问题。     

膜厚对不锈钢基厚膜电阻电性能的影响

为提高不锈钢基厚膜电阻浆料的重烧稳定性,采用丝网印刷、高温烧成等厚膜工艺制备了不锈钢基厚膜电阻,研究和分析了烧成膜厚度对方阻、电阻温度系数和重烧稳定性的影响规律和机理。结果表明,随着膜厚的增加,厚膜的方阻减小,电阻温度系数略有增大;当烧成Ag-Pd膜厚约为12μm时,厚膜电阻的重烧稳定性最佳,其方阻重烧变化率小于3%。     

影响高精细丝网印刷质量的因素

丝网印刷已成为微电子封装厚膜电路生产中的关键工艺技术。为满足微电子封装高精度、高密度的要求,从网版和印刷工艺参数两方面分析了影响高精细丝网印刷质量的因素。通过选用一定规格的不锈钢丝网,涂覆适当厚度的感光膜,开发出适合印刷50μm线宽和线间距的精密印刷网版;优化印刷工艺参数,将其中的刮刀压力、刮刀速度、离网间距分别控制在一定范围内,使印刷图形的变形量减少到200mm±30μm,实现线宽和间距为50μm、边缘清晰的精细印刷。     

表面活性剂对厚膜电子浆料流平性的影响

通过测量丝网印刷后膜层的表面粗糙度来表征厚膜电子浆料的流平性,研究了常用表面活性剂司班 85 及卵磷脂含量对浆料流平性的影响。结果表明,随着有机载体中表面活性剂含量增加,厚膜电子浆料的流平性变差。此外,还初步分析了表面活性剂对提高浆料的分散性和稳定性的作用。     

厚膜电阻器的噪声及其应用

本文综述了厚膜电阻器中噪声的种类，产生部位及机理的研究，重点介绍了厚膜电阻器的导电机制及1/f噪声的模型，并详细讨论了测量厚膜电阻器中1/f噪声的测量系统，在以上讨论的基础上，对厚度电阻器的低噪声化进行了简单的分析，展望了噪声作为可靠性表征参量的前景。     

Thick-film resistor quality indicator based on noise index measurements

A quality indicator for thick-film resistors based on noise index and resistance measurements is proposed. As this correlates resistor transport and noise characteristics and has mobility dimensions, we titled it to be noise reduced mobility. The experimental results for thick-film resistors, realized using three different resistor compositions with sheet resistances of 1, 10 and 100 kΩ m/sqr show that layers with sheet resistance of 10 kΩ0.25>m/sqr have minimum value of noise reduced mobility in comparison with layers formed using resistor compositions with sheet resistances of 1 and 100 kΩ m/sqr. The potential and resistance distributions measured along test resistors show that the noise reduced mobility is in correlation with thick-film inhomogeneity.     

新型厚膜片式NTC热敏元件研究

作者以Ｍｎ（１＋ｘ）Ｃｏ（２－ｘ）Ｏ４作热敏基料，掺适量ＭｅＭｎ２Ｏ４添加物，有效地降低了热敏浆料的方组，改善了元件的热稳定性，使厚膜片式ＮＴＣ热敏元件达到了实用化的要求。     

Laser sintering of thick-film PTC thermistor paste deposited by micro-pen direct-write technology

In this paper, laser sintering has been used to process thermal sensitive material deposited by micro-pen direct-write technology. Lines of thick-film PTC thermistor paste were deposited by micro-pen direct-write technology and irradiated by a continuous-wave laser with varied power density and scanning speed. Line widths, sheet resistivities and temperature coefficients of resistivity were measured as a function of laser power density, scanning speed, coating thickness and overlapped value. The mechanism of laser sintering thermistor paste was discussed. Laser sintering enabled finer thermistor lines to overcome the resolution limitation of micro-pen deposition without the use of any high temperature post processing. The thermistors exhibited excellent electrical performance and resistance tolerance equivalent to traditional oven-fired electronic paste.     

High Throughput Screening of Dynamic Silk‐Elastin‐Like Protein Biomaterials

The need for dynamic, elastomeric polymeric biomaterials remains high, with few options with tunable control of mechanical properties, and environmental responses. Yet the diversity of these types of protein polymers pursued for biomaterials‐related needs remains limited. Robust high‐throughput synthesis and characterization methods will address the need to expand options for protein‐polymers for a range of applications. Here, a combinatorial library approach with high throughput screening is used to select specific examples of dynamic protein silk‐elastin‐like polypeptides (SELPs) with unique stimuli responsive features, including tensile strength and adhesion. Using this approach, 64 different SELPs with different sequences and molecular weights are selected out of over 2000 recombinant E. coli colonies. New understanding of sequence‐function relationships with this family of proteins is gained through this combinatorial‐screening approach and can provide a guide to future library designs. Further, this approach yields new families of SELPs to match specific material functions.     

Study on thick-film PTC thermistor fabricated by micro-pen direct writing

Micro-pen direct-write technique has been used to fabricate thick-film PTC thermistor. Thick-film PTC thermistors were fired at 700, 750, 800, 850 and 900 °C. The microstructure and the development of the conductive phase were investigated by optical microscope, scanning electron microscopy and X-ray powder-diffraction analysis. Sheet resistivities and temperature coefficients of resistivity were measured as a function of firing temperature. The conductive phase of the PTC thermistor is based on a mixture of RuO₂, CuO and ruthenate. Pb₂Ru₂O_6.5 decomposes and the cubic-like CuO particle grows up to spinel-like particle during firing at temperature over 750 °C, while the sheet resistivities decrease from high values to a lowest values.     

丝网印刷银浆的银层断裂（裂缝）的防治与对策

在制造薄膜开关电路层或RFID标签天线层时,银层（导线）的银（碳）浆通常是用丝网印刷来完成的。在丝网印刷银浆中,银层产生断裂（裂缝）是常见的故障之一,它严重影响产品的质量,甚至成为废品。因此,在电路导线的银浆丝网印刷中要引起重视。文章主要分析探讨银浆丝网印刷中产生导线断裂（裂缝）的原因和防治对策。     

大腹圆蛛丝的SEM观察及其机械性质

本文应用扫描电镜（SEM）技术观察大腹圆蛛线的形态。结果表明，大腹圆蛛的拖牵引丝是由单根、双根、三根、四根的单丝纤维组成，且这种形态的拖牵丝表面也有区别。其包卵丝的伸长率、断裂强度与拖牵丝相当，但包卵丝的刚性逊于拖牵丝。大腹圆蛛的丝与其它种类的蜘蛛丝差异不大。     

PCB丝网印刷中怎样控制油墨的黏度和触变性

线路板在各种电子产品中的应用非常广泛,其质量和稳定性直接决定产品的质量。印制电路板（PCB）是电子丝网印刷中重要的印刷内容。在PCB印刷中,油墨的主要性能（如油墨的黏度和触变性）直接影响着PCB的印刷质量和生产速度。因此,在印刷中要注意熟悉和调控印刷油墨的黏度和触变性,保证PCB的丝网印刷的质量。     

Burnout of the organic vehicle in an electrically conductive thick-film paste

The burnout of the organic vehicle in a silver-particle, glass-free, electrically conductive, thick-film paste during firing in air was studied. For a vehicle consisting of ethyl cellulose dissolved in ether, burnout primarily involves the thermal decomposition of ethyl cellulose. The presence of ether with dissolved ethyl cellulose facilitates the burnout of ethyl cellulose. Excessive ethyl cellulose hinders the burnout. A high heating rate results in more residue after burnout. By interrupting the heating at 160°C for 15 min, the residue after subsequent burnout is diminished probably because of reduced temporal overlap of the processes of organic burnout and silver particle necking. By interrupting the heating at either 300°C or 385°C for 30 min, the temperature required for complete burnout is reduced. The addition of silver particles facilitates drying at room temperature and burnout upon heating.