铜丝键合技术研究及市场趋势综述

集成电路芯片的内部互联主要使用键合技术。本文简要介绍了集成电路封装的三种键合方式及其原理;对目前广泛使用的键合金丝、键合铝丝、键合铜丝的性能进行了分析和对比,突出了键合铜丝替代传统键合材料的优势,并对改进的镀钯键合铜丝进行了介绍;最后从政策、供求等方面对键合铜丝的市场发展趋势进行了分析。     

键合用金丝的可靠性及其评价

键合是集成电路生产中的一道重要工序,它是把集成电路芯片与引线框架连接起来的操作。键合的好坏直接影响集成电路的性能。集成电路键合用引线以金丝为主,极少数采用铝丝。纯铝丝太软,键合强度较低,而且很难拉制极细丝。尽管已研制出铝合金丝,但仍然满足不了集成电路高可靠性的要求。因此,迄今国际上大量使用金丝作为引线,而且采用了先进的全自动高速球焊工艺,适合于这种球焊工艺的金丝称为高速键合金丝,本文讨论了高速键合金丝的可靠性问题并对此作一评价。1.高速键合金丝的种类及其特点不同的集成电路对金丝的要求也不尽相同,常用的线经为18μm～38μm,其中以25-μm 居多。表1、图1、图2示出了几个有代表性规格的金丝及其力学性能。     

纯度为99.9999％的铜丝

日本住友金属矿业公司已发展了一种用于大规模集成电路引线、纯度为99.9999％的铜丝。高纯铜是用99.99％纯铜经电解提纯获得。此种具有0.2μΩcm比电阻的铜丝有可能取代传统用的金丝。另外,日本矿业公司也已发展了一种99.9999％纯铜,其S、Te含量分别低于0.06ppm和0.05ppm,维氏硬度为40—45。其应用包括引线和激光镜。日本矿业公司目前在他的中心研究试验室中,每月生产这种材料300公斤。     

Cu-Cr触头材料的制备方法及进展

简要介绍了Cu-Cr合金触头材料的结构特点及其优良性能；综述了近年来Cu-Cr合金制备技术的进展；介绍了目前制备Cu-Cr触头材料的几种常用方法；重点介绍了触头材料的几种先进制备工艺；比较了各种制备技术的优缺点及其应用范围；展望了触头材料的发展趋势。     

从专利文献看键合铜丝的发展

随着当今微电子器件日趋小型化、高性能化的特点以及国家节能减排、降本增效的发展要求,键合铜丝将逐步取代键合金丝成为微电子封装用主流键合材料。本文根据键合铜丝专利文献综述了键合铜丝的发展现状,介绍了键合铜丝的微合金化研究动向,指出键合铜丝的研究重点是通过最佳微合金元素设计和微合金化工艺控制来提高铜丝的强度、键合性能与可靠性。     

高导耐温锆铜合金的研制

本文叙述了锆铜合金制备中,添加剂的选择和锆含量的确定,锆铜的熔炼工艺,以及固溶处理对导电性能和抗软化性能的影响。加工必须采用大变形度(>99％),以使晶粒细化。文中还就锆铜丝的主要技术数据与日本日立公司锆铜丝进行了对比。对比说明,国产锆铜丝已完全能代替日本进口材料。     

江苏省冶金研究所常熟材料厂集成电路引线用超细长金丝研制成功

引线金丝是制造集成电路及分立器件的重要结构材料,主要用于集成电路的键合。(亦称作键合金丝)适合于集成电路高速键合机用的超细长金丝国内一直依赖进口解决。我国把这项研究列为“六·五”、“七·五”的重点攻关项目。江苏省科季(89)88号文列入科研项目。省冶金研究所在对该项目进行了深入细致的调研和论证后,与常熟市合作建办了江苏省冶金研究所常熟材料厂,在国内首次引进了引线金丝生产线,并根据我国的具体情况,在比较和探求了多种方案后,自行研究设计了生产超细长金丝的配方和工艺,经过半年多的生产实践已生产出30多万米的合格长金丝、(直径为18～38微米)。所生产的三种型号、数十种规格的     

钢包喂铝丝试验

重钢在平炉、转炉用的不同容量钢包中，对不同生产工艺条件和不同钢种进行钢包喂铝丝试验，取得较好的冶金效果和经济效益；对各种工艺条件下的合理工艺参数，影响铝回收率的诸多因素进行了研究。     

单晶铜丝的发展前景

介绍单晶铜丝,以其优良的力学性能和便宜的价格,在键合行业逐渐取代金丝,大量应用于集成电路、半导体分立器件;同时,单晶铜在数据传输中因无晶界对数据造成的反射和散射,正广泛应用于高保真的音频、视频数据线和高标准通信网络线缆传输。     

钢包喂铝丝工艺试验

本文介绍了平炉、转炉不同钢包容量、不同生产工艺条件和不同钢种进行钢包喂铝丝试验的情况。初步探索了在各种条件下的喂丝工艺参数,对影响铝回收率的诸多因素进行了分析研究。     

镀镍丝的电镀工艺过程及故障分析

文章介绍了镀镍丝与电镀镍的生产工艺，详细分析了影响电镀镍工艺的诸因素，提出了电镀镍生产过程中故障排除的方法与举措，可供电镀业同类型生产厂家的工程技术人员参考和借鉴。     

Embolic materials for endovascular treatment of cerebral lesions

Recently developed soft microcatheters can be maneuvered endovascularly into the brain, permitting treatment of lesions without conventional neurosurgery. Progress in biomaterial science has contributed significantly to the development of this new therapeutic modality termed intravascular neurosurgery or interventional neuroradiology. Although embolic materials play an important role, ideal materials have yet to be devised. Various embolic materials in clinical use are reviewed, such as cyanoacrylates, ethylene-vinyl alcohol copolymer mixtures, Ethibloc, ethanol, estrogen, poly(vinyl acetate), cellulose acetate polymer, poly(vinyl alcohol), gelatin sponges, microfibrillar collagen, surgical silk sutures, detachable balloons, and coils. The materials are reviewed in the context of treatment application for various brain lesions, such as arteriovenous malformations, cerebral aneurysms, and head and neck tumors. Further developments in biomaterial polymer science can bring about progress against brain diseases.     

影响线材包装质量的探讨

分析了线材生产时,吐丝机的吐丝管、吐丝机速度、吐丝温度控制及线材收集等因素对打包质量的影响,并简要叙述了生产中出现问题的原因及解决措施。     

Experiments on animals to investigate the suitability of perforating corneal sutures (author's transl)

Injuries of the cornea in rabbits are treated with perforating sutures using non-traumatic material (nylon and silk 9-0). Postoperative examinations with fluorescein showed the absence of fistulas along the suture in all cases. Histological examinations of the lacerations and sutures three respectively five weeks after the operation did not reveal any epithelial growth in the anterior chamber nor endothelial growth in the suture canal. We believe, therefore, that the use of perforating corneal sutures no longer presents any risks, especially when materials of up to 15-0 are used which are readily available.     

Glycine and alanine synthesis enzymes in the tissues of the silkworm during its development

The activity of enzymes of glycine and alanine synthesis (glutamate-pyruvate aminotransferase, aspartate-beta-decarboxylase, threonine aldolase, serine hydroxymethyltransferase, alanine-glyoxylate aminotransferase, aspartate aminotransferase) is studied in haemolymph, fat body, fibroin and sericine divisions of silk gland of silkworm Bombyx mori at terminal period of larva development. Alanine-glyoxylate aminotransferase activity in fibroin division of silk gland (34,6 mu mole of glycine/mg of protein/min-10(-3)), alanine aminotransferase--in sericine division (36,0 mu mole of alanine/mg of protein/min-10(-3)) aspartate aminotransferase 27,3 mu mole of glutamic acid/mg of protein/min-10(-3)) and alanine aminotransferase (35,8 mu mole of alanine/mg of protein/min-10(-3)) on fat body. The ratio of alanine-glyoxylate aminotransferase/glutamate-pyruvate aminotransferase activities in posterior division of silk gland is near to glycine/alanine ratio in silk fibroin. The character of the enzymes activity in silkworm tissues correlates with the silk formation rate.     

会东淌塘铜矿矿床成因分析及其找矿方向

会东淌塘铜矿矿区地层为元古界会理群淌塘组,主要岩性为炭质绢云千枚岩、绢云千枚岩、炭质千枚岩、绢云千枚岩等浅变质岩组成,该矿床为埋藏较深的小型隐伏矿,在地质勘探期间一直认为矿区总体上是一单斜地层,按照这一指导方针圈定的矿体与矿山开采所揭露的矿体出入较大,笔者结合近年来矿山收集到的实际地质资料,对矿区地质特征做了系统的总结和描述,对矿区总体构造进行了重新认识,对矿体特征进行了重新总结,对矿床成因提出了新的探讨和研究,并就矿山后续地质找矿提出找矿建议。     

Translational pauses during the synthesis of proteins and mRNA structure

Translational pauses are observed during a spider fibroin synthesis (1,2). The spider major ampullate (dragline) silk of the spider Nephila clavipes is composed of multiple proteins. The amino acid sequences of the partial cDNA clones for the two major dragline silk fibroin components (Spidroin 1 and 2) exhibit repetitive motifs (3,4). Our detailed inspection of the nucleotide sequences of the repetitive motifs revealed highly selective site-specific codon usage patterns within a motif, suggesting that the secondary structure of the spider fibroin mRNA is optimized by the nucleotide sequence of the fibroin gene. The results, combined with our preceding results on silk fibroin from Bombyx mori (5) suggest that translational pauses of spider silk are interpreted in terms of the mRNA secondary structure.     

Chondrosarcoma of the nasal septum

120 pieces of silk suture (1# & 4#) were sterilized with formaldehyde at different time period. Group II and III each had 20 pieces and was disinfected with ethylene oxide or high pressure respectively. The tension of each silk suture was measured with tensomether. The result showed that there was no significant difference compared with the control groups (P > 0.05). This suggests that silk suture maintains the same tension in the experiments after repeated sterilization with formaldehyde, with ethylene oxide, or with highpressure sterilization once.     

Primary structure and possible functions of a trypsin inhibitor of Bombyx mori

A protein with a low molecular mass of 6027 was purified from cocoon shell of silkworm, Bombyx mori. Two-dimensional polyacrylamide gel electrophoresis (2D/PAGE) resolved this protein into a single spot with pI 4.3 and Mr 6000. Amino acid sequence analysis revealed that this protein consists of 55 amino acids, six of these being cysteine residues and is highly homologous to bovine pancreatic trypsin inhibitor-type inhibitors. The 6-kDa protein is heat stable and acid stable and inhibits bovine trypsin by forming a low-dissociation complex with trypsin in a 1 : 1 molar ratio (Ki = 2.8 x 10-10), but does not alpha-chymotrypsin. This cocoon shell-associated trypsin inhibitor (CSTI) was thus concluded to belong to the bovine pancreatic trypsin inhibitor class. CSTI was developmentally regulated in the silk gland at the final stage of larval growth, and its specific distribution in the middle silk gland, an organ in which silk proteins are stored during the final larval instar, occurred before the onset of spinning. This inhibitor protects the tryptic degradation of fibroin light (L) chain in vitro. These results suggest that this trypsin inhibitor may play an important part on regulating proteolytic activity in the silk gland or protecting silk proteins from degradation during histolysis.