激光表面熔覆SiCp/Ni-Cr-B-Si-C涂层的组织演化及其相确定

运用激光熔覆技术在ＡＩＳＩ１０４５钢表面制备了３０ｖｏｌ－％ＳｉＣｐ／Ｎｉ－Ｃｒ－Ｂ－Ｓｉ－Ｃ涂层。ＳＥＭ和ＴＥＭ观察分析表明：ＳｉＣｐ在熔覆过程中完全溶解;涂层结合区组织为共晶结构;涂层组织由初生石墨球Ｇ,分布在γ－Ｎｉ固溶体枝晶中的Ｍ２３（Ｃ,Ｂ）６细小网状树枝晶以及少量Ｎｉ＋Ｎｉ３（Ｂ,Ｓｉ）层片状共晶组成;Ｓｉ在Ｎｉ固溶体中的固溶度显著增大,高达１４．４１ｗｔ－％;Ｍ２３（Ｃ,Ｂ）６含有高密度堆垛层错;Ｎｉ３（Ｂ,Ｓｉ）相具有长周期结构。     

激光熔覆WCp/Ni-Cr-B-Si-C自熔合金复合涂层的显微结构及干滑动磨损

运用激光熔覆技术在４５＃钢表面制备了ＷＣｐ增强Ｎｉ－Ｃｒ－Ｂ－Ｓｉ－Ｃ复合涂层。含量为３０ｖｏｌ－％ＷＣ典型涂层的ＸＲＤ,ＳＥＭ和ＴＥＭ分析表明,ＷＣｐ在熔覆的熔化阶段发生部分溶解和分解。激光熔体凝固时形成的微观组织由Ｎｉ＋Ｎｉ３Ｂ共晶基体上分布的杆（或薄片）状α－Ｗ２Ｃ,块状β－Ｗ２Ｃ和四方形η１碳化物Ｍ６Ｃ相组成。这类碳化物主要含Ｗ,并含大量Ｃｒ。销－环式干滑动磨损试验表明,当ＷＣｐ含量约为３０ｖｏｌ－％时,磨损抗力最大     

用化学共沉SrTiO_3研制钛酸锶铋介质陶瓷

采用ＸＲＤ、ＳＥＭ、ＥＤＡＸ、粒度分析等手段研究了在（１－ｘ）ＳｒＴｉＯ３ｘＢｉ２Ｏ３·３ＴｉＯ２（简称ＳＢＴ）系统中采用化学共沉ＳｒＴｉＯ３时，Ｂｉ２Ｏ３·３ＴｉＯ２的含量对介电性能和显微结构的影响。发现当其摩尔分数ｘ小于１０％时，结构为单相固溶体，εｒ随ｘ的增加而增加；当ｘ大于１０％时，为复相结构，εｒ开始下降。这个结果与采用ＳｒＣＯ３和ＴｉＯ２固相合成的ＳｒＴｉＯ３烧块时的结果相近，变化趋势一致。但化学共沉ＳｒＴｉＯ３之晶粒细小，杂质少，故使所制介质具有非常优异的介电性能。     

金属诱导法低温多晶硅薄膜的制备与研究

利用金属诱导晶化（Ｍｅｔａｌ Ｉｎｄｕｃｅｄ Ｃｒｙｓｔａｌｌｉｚａｔｉｏｎ,ＭＩＣ）的方法研究了ａ－Ｓｉ／Ｎｉ的低温晶化,ＭＩＣ的晶化温度降低到４４０℃。采用ＸＲＤ、Ｒａｍａｎ、ＳＥＭ和ＸＰＳ等手段研究了Ｎｉ－ＭＩＣ多晶硅薄膜的特性,分析了薄膜结构和组成,讨论了晶化过程的机理。     

TiN_p／镍基合金复合耐磨涂层的激光熔覆

在４５钢表面用激光束熔覆了ＴｉＮ_ｐ／镍基合金复合耐磨涂层，对涂层的组织和滑动磨损性能进行了分析，并讨论了不同激光工艺参数下涂层稀释度的变化情况。熔覆层由ＴｉＮ颗粒、γ－Ｎｉ初晶以及γ－Ｎｉ＋（Ｆｅ，Ｃｒ）_２３（ＣＢ）_６共晶构成。初晶γ－Ｎｉ中观察到高密度的位错，共晶化合物（Ｆｅ，Ｃｒ）_２３（ＣＢ）_６中出现了大量的层错亚结构，这些特征均使得涂层中的基体相得到了强化。在激光熔覆过程中硬质相ＴｉＮ颗粒边缘发生了部分溶解，冷却过程中重新凝固的ＴｉＮ以细小枝晶状独立形核析出。复合涂层中由于ＴｉＮ颗粒的存在使得涂层硬度显著提高，在摩擦系数不明显变大的前提下耐磨性提高了３倍。     

三元硅化物（CoxNi1—x）Si2薄膜的制备及特性

在Ｓｉ（１００）衬底上用离子束溅射方法淀积Ｎｉ,Ｃｏ,Ｔｉ薄膜,形成Ｃｏ／Ｎｉ／Ｓｉ,Ｎｉ／Ｃｏ／Ｓｉ和Ｃｏ／Ｎｉ／Ｓｉ等结构,通过氮气中快速热退火反应生成三元硅化物（ＣｏｘＮｉ１－ｘ）Ｓｉ２。用ＡＥＳ,ＸＲＤ,ＲＢＳ沟道谱,ＳＥＭ及四探针等方法（ＣｏｘＮｉ１－ｘ）Ｓｉ２薄膜的物理特性和电学特性进行了测试,在Ｓｉ衬底上Ｃｏ,Ｎｉ多层膜经快速热退火可形成高电导的（ＣｏｘＮｉ１－ｘ）Ｓｉ２薄膜,其电阻     

Co／Ti／Si三元固相反应外延生长CoSi_2薄膜

研究采用Ｃｏ／Ｔｉ／Ｓｉ三元固相反应的方法生长外延ＣｏＳｉ２薄膜．通过选择适当的热处理条件，采用多步退火，在Ｓｉ（１００）和Ｓｉ（１１１）衬底上均成功获得外延ＣｏＳｉ２薄膜．实验用ＸＲＤ、ＴＥＭ、ＲＢＳ／ｃｈａｎｎｅｌｉｎｇ等测试技术分析ＣｏＳｉ２薄膜外延特性，得到的ＣｏＳｉ２薄膜的ＲＢＳ／ｃｈｎｎｅｌｉｎｇ最低产额Ｘｍｉｎ达到１０－１４％．实验对ＣｏＳｉ２／Ｓｉ（１１１）样品，分别沿Ｓｉ衬底的＜１１０＞和＜１１４＞晶向进行背散射沟道测量．结果发现，沿Ｓｉ＜１１０＞晶向得到的ＣｏＳｉ２背散射沟道产额显著高     

新型复相陶瓷刀具材料JX—2—I的界面结构及其对材料性能的影响

本文利用ＴＥＭ研究了新型复相陶瓷刀具材料ＪＸ－２－Ｉ的界面结构，结果表明，在ＪＸ－２－Ｉ中Ａｌ２Ｏ３／ＳｉＣｗ（氧化铝／碳化硅晶须）界面和Ａｌ２Ｏ３／ＳｉＣｐ（碳化硅颗粒）界面结合良好，形成了具有较高强度的微观结构，发现在ＳｉＣｗ，ＳｉＣｐ和Ａｌ２Ｏ３晶粒上均有位错产生，在ＳｉＣｐ和Ａｌ２Ｏ３上有孪晶产生，分析表明，位错和孪晶的产生均吸收大量的断裂能，提高材料的断裂韧性，改善ＪＸ－２－Ｉ材料的整体     

三元硅化物(Co_xNi_(l-x))Si_2薄膜的制备及特性

在Ｓｉ（１００）衬底上用离子束溅射方法淀积Ｎｉ,Ｃｏ,Ｔｉ薄膜,形成Ｃｏ／Ｎｉ／Ｓｉ,Ｎｉ／Ｃｏ／Ｓｉ和Ｃｏ／Ｎｉ／Ｓｉ等结构,通过氮气中快速热退火反应生成三元硅化物（ＣｏｘＮｉｌ－ｘ）Ｓｉ２。用ＡＥＳ,ＸＲＤ,ＲＢＳ沟道谱,ＳＥＭ及四探针等方法对（ＣｏｘＮｉｌ－ｘ）Ｓｉ２薄膜的物理特性和电学特性进行了测试,在Ｓｉ衬底上Ｃｏ,Ｎｉ多层膜经快速热退火可形成高电导的（ＣｏｘＮｉｌ－ｘ）Ｓｉ２薄膜,其电阻率在１５～２０μΩ·ｃｍ之间。Ｃｏ／Ｎｉ／Ｔｉ／Ｓｉ（１００）多层结构固相反应可以得到外延（ＣｏｘＮｉｌ－ｘ）Ｓｉ２薄膜。（ＣｏｘＮｉｌ－ｘ）Ｓｉ２的晶格为ＣａＦ２立方结构,晶格常数介于ＣｏＳｉ２和ＮｉＳｉ２之间。通过热处理和选择腐蚀等工艺,可在有ＣＭＯＳ图形的衬底上形成自对准的三元硅化物源漏接触和栅极互连图形。     

1微米硅栅CMOSASIC制造中RIE的应用

本文主要介绍１ｕｍ双阱双层金属布线硅栅ＣＭＯＳ专用集成电路制造中采用先进的反应离子刻蚀技术，对多种材料如ＬＰＣＶＤ、Ｓｉ３Ｎ４、ＰＥＣＶＥＳｉ３Ｎ４、热ＳｉＯ２、ＰＥＶＥＤＳｉＯ２、ＰＳＧ、ＢＰＳＧ、多晶硅和Ａｌ－Ｓｉ（１．０％）－Ｃｕ（０．５％）合金等进行高选择比的，各向异性刻蚀的工艺条件及其结果。获得上述各种材料刻蚀后临界尺寸（ＣＤ）总损失＜０．０８ｕｍ的优良结果。此外还分析讨论了被选择的刻蚀     

激光熔覆Ni基SiC合金涂层组织与性能的研究

利用5kWCO2连续波激光器在16Mn钢基材表面对含20%(体积比)SiC陶瓷粉末的镍基自熔性合金粉末进行激光熔覆得到Ni基SiC合金涂层(NiSiC)。研究了合金涂层的组织形貌及相结构,并用单纯的镍基合金涂层(Ni60)进行了显微硬度及滑动磨损性能的对比试验。结果表明,NiSiC合金涂层由γ枝晶及其间的共晶组织组成,主要组成相为γ-Ni,γ-(Ni,Fe)固溶体和(Cr,Fe)7C3,Cr23C6及(Cr,Si)3Ni3Si等化合物。添加SiC的镍基合金涂层NiSiC比单纯的镍基合金涂层Ni60具有较高的硬度和耐磨性。     

凝固条件对γ-Ni/Mo2Ni3Si合金凝固组织的影响

设计并采用激光熔炼工艺制备出镍基固溶体γ增韧的Mo_2Ni_3Si三元金属硅化物合金。差式扫描量热分析(DSC)及高温金相实验表明,该合金共晶温度约1287℃,液相线温度约1355℃。研究了该Mo_2Ni_3Si合金在炉冷、水冷及激光表面熔凝条件下的凝固组织。结果表明,在炉冷及水冷条件下,随着凝固冷却速度的提高,合金中Mo_2Ni_3Si初生枝晶体积分数降低、二次枝晶臂间距减小,但激光表面快速熔凝合金中Mo_2Ni_3Si初生枝晶体积分数急剧增加(62％)。激光表面快速熔凝γ/Mo_2Ni_3Si合金由于组织细小,且基体γ相被Mo及Si元素过饱和固溶,具有最优异的力学性能(显微硬度600HV);炉冷Mo_2Ni_3Si合金凝固组织初生枝晶上分布着许多显微裂纹,且显微组织为粗大的二相组织,力学性能较差。     

激光熔覆Ni31Si12/FeNi金属硅化物复合材料涂层显微组织与耐蚀性研究

以Ni、Si元素粉末为原料,利用激光熔覆技术在A3钢表面制得了Ni_(31)Si_(12)/FeNi金属硅化物复合材料涂层。分析了该涂层显微组织,采用测定阳极极化曲线的方法评价了该涂层在0.5mol/l H_2SO_4水溶液中的耐蚀性能,考察了添加少量合金元素Cr对涂层耐酸腐蚀性能的影响。结果表明:激光熔覆Ni_(31)Si_(12) /12/FeNi金属硅化物复合材料涂层组织由带状Ni31Si12初生相及带间FeNi/Ni_(31)Si_(12)/12共晶组成,涂层表面平整、组织细小、与基体间为完全冶金结合;涂层组织显微硬度在HV650—75O之间,沿层深分布均匀;涂层组织组成相Ni_(31)Si_(12)/FeNi本身具有良好的耐酸腐蚀性能,具有快速凝固成分均匀的显微组织,激光熔覆Ni_(31)Si_(12)//FeNi金属硅化物复合材料涂层在H_2SO_4水溶液中表现出良好的耐蚀性。合金元素Cr的添加进一步提高了涂层的耐酸腐蚀性能。     

激光熔覆镍基金属陶瓷涂层的组织性能研究

运用 5kWCO2 连续激光器在 16Mn钢表面激光熔覆镍基B4 C金属陶瓷层 (NB4 C)和镍基SiC金属陶瓷层(NSiC) ,研究了两种激光熔覆层的组织、结构、显微硬度及滑动磨损特性 ,并用激光熔覆镍基合金层 (Ni6 0 )进行了滑动磨损对比试验。结果表明 ,熔覆合金层显微组织由枝晶固溶体及其间细密的共晶组织组成 ,NB4 C熔覆层主要组成相为γ Ni,γ (Ni,Fe) ,(Cr,Fe) 7C3,CrB ,Ni3B ,Fe2 B ,Fe2 3(C ,B) 6 和B4 C等 ,NSiC熔覆层主要组成相为γ Ni,γ (Fe,Ni) ,(Cr,Fe) 7C3,Cr2 3C6 和 (Cr ,Si) 3Ni3Si等。三种激光熔覆层的显微硬度及耐滑动磨损性能由高到低的顺序为 :NB4 C→NSiC→Ni6 0。     

Linewidth effect and phase control in Ni fully silicided gates

The scalability of Ni fully silicided (FUSI) gate processes to short gate lengths was studied for NiSi, Ni/sub 2/Si, and Ni/sub 31/Si/sub 12/. It is shown that the control of the deposited Ni-to-Si ratio is not effective for phase and V/sub t/ control at short gate lengths. A transition to Ni-richer phases at short gate lengths was found for nonoptimized NiSi and Ni/sub 2/Si processes with excessive thermal budgets, resulting in significant V/sub t/ shifts for devices on HfSiON consistent with the difference in work function among the Ni silicide phases. Linewidth-independent phase control with smooth V/sub t/ rolloff characteristics was demonstrated for NiSi, Ni/sub 2/Si, and Ni/sub 31/Si/sub 12/ FUSI gates by controlling the Ni-to-Si reacted ratio through optimization of the thermal budget of silicidation (prior to selective Ni removal). Phase characterization over a wide temperature range indicated that the process windows for scalable NiSi and Ni/sub 2/Si are less than or equal to 25 /spl deg/C, whereas a single-phase Ni/sub 31/Si/sub 12/ is obtained over an /spl sim/200/spl deg/C temperature range.     

铁基合金激光熔覆层组织分布及开裂敏感性研究

在45#钢基底上进行了铁基合金粉末激光熔覆实验。利用扫描电镜观察了熔覆层横断面的金相显微组织形态,对组织的不同特征部位进行了EDS能谱分析,使用X射线衍射仪对熔覆层进行物相分析。结合熔覆层的组织成分分布和激光熔覆过程中组织凝固的特点,分析得到熔覆层中存在少量的Si和B与Fe、Cr、Ni、O结合形成的低熔点共晶,低熔点共晶分布在晶界,尤其是夹杂在熔覆层表层部分,成为裂纹源。调节熔覆材料的成分,减少低熔点共晶产生,可以有效抑制熔覆层的裂纹敏感性。     

Fabrication and Microstructures of Sequentially Electroplated Sn-Rich Au-Sn Alloy Solders

Three Sn-rich, Au-Sn alloy solders with eutectic, hypoeutectic, and hypereutectic Sn compositions were fabricated by sequential electroplating of Au and Sn and then the dual-layer films were reflowed at 250°C. The microstructures and phase compositions of the deposited Au/Sn dual-layer film and the reflowed Sn-rich Au-Sn alloys were studied. Microhardness values of the different phases or phase zones for the reflowed alloys were also tested. Finally, two Si wafers were bonded together with the eutectic Sn-rich Au-Sn alloy solder. For as deposited Au/Sn dual-layer films, reaction between Au and Sn occurs at room temperature leading to the formation of Au₅Sn, AuSn, and AuSn₂ at the Au/Sn interface. After reflowing at 250°C, two phases remain, Sn and AuSn₄, with the morphology and phase distribution depending on the original solder composition. In the Sn-rich, eutectic Au-Sn alloy, AuSn₄ particles are distributed uniformly in the Sn matrix. In the Sn-rich hypoeutectic/hypereutectic Au-Sn alloys, the proeutectic phase, AuSn₄ (Vickers hardness, Hv 125) or Sn (Hv 14.2), is larger in size and is surrounded by the eutectic zone (Sn + AuSn₄) (Hv 16.1). In all cases, the TiW adhesion and barrier layer remains intact during annealing. After reflowing at 250°C under a pressure of 13 kPa, two Si wafers are joined by the Sn-rich eutectic Au-Sn alloy solder, without crack or void formation at the Si wafer/solder interface or within the solder.     

Interfacial microstructure of Pb-free and Pb-Sn solder balls in the ball-grid array package

Ball-grid array (BGA) samples were aged at 155°C up to 45 days. The formation and the growth of the intermetallic phases at the solder joints were investigated. The alloy compositions of solder balls included Sn-3.5Ag-0.7Cu, Sn-1.0Ag-0.7Cu, and 63Sn-37Pb. The solder-ball pads were a copper substrate with an Au/Ni surface finish. Microstructural analysis was carried out by electron microprobe. The results show that a ternary phase, (Au,Ni)Sn₄, formed with Ni₃Sn₄ in the 63Sn-37Pb solder alloy and that a quaternary intermetallic phase, (Au,Ni)₂Cu₃Sn₅, formed in the Sn-Ag-Cu solder alloys. The formation mechanism of intermetallic phases was associated with the driving force for Au and Cu atoms to migrate toward the interface during aging.     

激光熔敷Ti5Si3/NiTi金属间化合物复合材料涂层组织与高温抗氧化性能研究

以Ti—Si—Ni混合合金粉末为原料,利用激光熔敷技术,在高温、高强钛合金BT9表面制得了以金属间化合物Ti5Si3为强化相、以金属间化合物NiTi为基体的金属间化合物快速凝固高温抗氧化复合材料涂层。在1000℃恒温氧化50小时的试验条件下测试了涂层的抗氧化性及氧化动力学曲线,分析了复合材料涂层及氧化膜的显微组织结构及相组成。     

Impact of surface preparation on nickel-platinum alloy silicide phase formation

Nickel based silicide films were prepared by annealing nickel-platinum layers deposited on n-doped Si substrates. We report on the evolution of the crystallography, the phase formation and the redistribution of contaminants on blanket wafers during silicide formation as a function of the silicon surface preparation prior to Ni(Pt) deposition. In situ argon sputtering etch creates a contamination layer which modifies phase texture during the formation of the first Ni silicide phases. Using remote pre-clean results in a predominant Ni₂Si phase with preferential grain orientation after a first anneal. After a second anneal, the monosilicide forms, regardless of what nickel rich silicide phase was initially formed and regardless of the surface preparation prior to metal deposition.