CHARACTERIZATION OF Sil-x-yGexCy FILMS GROWN BY ION IMPLANTATION AND SUBSEQUENT SOLID PHASE EPITAXY

Si1 y GexCy ternary alloy films were grown on monocrystalline silicon substratesby C+ ion implantation and subsequent solid phase epitaxy (SPE). Two-step anneal-ing technique was employed in the SPE. The structure and electrical properties of thealloy films were determined using Fourier transform infrared spectroscopy and vander Pauw Hall measurements, respectively. With the optimization of two-step anneal-ing technique for the implanted Si1-x-y GexCy layers, a certain amount of C atomsoccupied substitutional sites and no SiC was formed.     

Thermal performance of sputtered Cu films containing insoluble Zr and Cr for advanced barrierless Cu metallization

Pure Cu films and Cu alloy films containing insoluble substances(Zr and Cr)were deposited on Si(100)substrates,in the presence of interfacial native suboxide(SiOx),by magnetron sputtering.Samples were vacuum annealed between 300℃and 500 ℃to investigate effects of Zr and Cr additions on the thermal performance of Cu films.After annealing,copper silicides were found in the Cu(Zr)films,while no detectable silicides were observed in Cu and Cu(Cr)films.Upon annealing,Zr accelerated the diffusion and reaction between the film and the substrate,and lowered the thermal stability of Cu(Zr)alloy films on Si substrates,which was ascribed to the‘purifying effect’of Zr on the Si substrates.Whereas,Cr prohibited the agglomeration of Cu films at 500℃and decreased the surface roughness.As a result,the diffusion of Cu in Si substrates for Cu(Cr)films was effectively inhibited.In contrast to the high resistivity of Cu(Zr)films,the final resistivity of about 2.76μΩ·cm was achieved for the Cu(Cr)film.These results indicate that Cu(Cr)films have higher thermal stability than Cu(Zr)films on Si substrates and are preferable in the advanced barrierless Cu metallization.     

The Characterization of Sputtered Zr-Ge-N Thin Films as Diffusion Barriers Between Copper and Silicon

The main purpose of the present micro-structural analysis by transmission electron microscopy(TEM)and X-ray diffraction(XRD)was to investigate whether amorphous Zr-Ge-N films are a potential candidate as a diffusion barrier for Cu wiring used in Si devices.The Zr-Ge-N films were prepared by a radio frequency(RF)reactive magnetron sputter-deposition technique using N2 and Ar mixed gas,and the film structure was found to be sensitive to the gas flow ratio of N2 vs.Ar during sputtering.Polycrystalline Zr-Ge-N films were obtained when the N2/(Ar+N2)ratio was smaller than 0.2 and amorphous-like Zr-Ge-N films were obtained when the ratio was larger than 0.3.Diffusion barrier test was performed by annealing the Cu/Zr-Ge-N/Si film stack under Ar atmosphere.The deposited Zr-Ge-N(C)films remained amorphous even after high temperature annealing.The Cu diffusion profile in the film was assessed by the Auger electron spectroscopy(AES).The results indicate that Cu diffusion was minimal in amorphous Zr-Ge-N(C)films even at high annealing temperatures of 800℃.     

Ru incorporation on marked enhancement of diffusion resistance of multi-component alloy barrier layers

In this study, amorphous AlCrTaTiZr quinary alloy and 20 at.% Ru-incorporated AlCrTaTiZrRu senary alloy films were developed as diffusion barrier layers to inhibit Cu diffusion in interconnect structures. Under annealing at 700 °C, the interdiffusion of Cu and Si through the AlCrTaTiZr quinary alloy layer of 50 nm thick occurred, and compounds including Cu₃Si consequently formed. In comparison, at 800 °C, the interdiffusion was still effectively retarded by the Ru-incorporated AlCrTaTiZrRu senary alloy layer of only 5 nm thick without obvious formation of silicides. It suggests the high diffusion resistance of the Ru-incorporated barrier layer possibly attributed to the large lattice distortions caused by the addition of extra-large-sized Ru atoms.     

Effect of annealing on the microstructures and Vickers hardness at room temperature of intermetallics in Mo-Si system

The microstructures and Vickers hardness at room tempcrature of arc-melting processed intermetallics of Mo5Si3-MoSi2 hypoeutectic alloy and hypereutectic alloy annealed at 1200℃ for different time were investigated. Lamellar structure consisted of MosSi3 (D8m) phase and MoSi2 (C11b) phase was observed in all the alloys. For Mo5Si3-MoSi2 hypoeutectic alloy, the lamellar structure was found only after annealing and developed well with fine spacing on the order of hundred nanometers after annealing at 1200℃ for 48 h. But when the annealing time was up to 96 h, the well-developed lamellar structure was destroyed. For Mo5Si3-MoSi2 hypereutectic alloy, the lamellar structure was found both before and after annealing. However the volume fraction and spacing of the lamellar structure did not change significantly before and after annealing. The effects of the formation, development and destruction of lamellar structure on Vickers hardness of alloys were also investigated. When Mo5Si3-MoSi2 hypoeutectic alloy annealed at 1200℃ for 48 h, the Vickers hardness was improved about 19% compared with that without annealing and formation of lamellar structure. The highest Vickers hardness of Mo5Si3-MoSi2 hypereutectic was increasing about 18% when annealing at 1200℃ for 48 h.     

Lanthanum silicate thin films for SOFC electrolytes synthesized by magnetron sputtering and subsequent annealing

Thin films of La and Si with Si/(La + Si) atomic ratios ranging from 0.36 to 0.44 were produced by magnetron sputtering in pure Ar. For all compositions, the apatite-like La_9.33Si₆O₂₆ phase was formed during annealing in air at 900 °C. A preferential orientation was developed during annealing of the films with higher silicon content while formation of oxide impurities was detected for the films with less silicon. Silicon segregation to the thin film/substrate interface was observed after annealing for thin films with higher Si/(La + Si) atomic ratios. The higher ionic conductivity values were obtained with the films with lower silicon content (2.81 × 10^− 3 Scm^− 1 at 800 °C for the film with Si/(La + Si) atomic ratio of 0.36). This film presented the lower activation energy E_a (0.94 eV).     

Annealing effects on microstructure and properties of Ta-Al thin film resistors

The Ta-Al thin film resistor has been used as a heating element of the thermal bubble inkjet printhead with several millions of thermal cycle operations between room temperature and about 350 °C. In this paper, the thermal stability of Ta-Al alloy films was investigated by the variation of phase transformation, microstructure and resistivity at annealing temperatures of 450-650 °C for 1 h. Three kinds of Ta-Al films were prepared with average Ta/Al atomic composition ratios of about 2/1, 1/1 and 1/2, respectively. The Ta-Al film with composition ratio of about 1/1 exhibits amorphous-like microstructure with nanocrystalline grains embedded in an amorphous matrix. The thermal stability is strongly related to the composition and microstructure in Ta-Al alloy. The best thermal stability of Ta-Al films occurs in Ta-rich alloy up to 650 °C and the worst occurs in Al-rich alloy with phase transformation as low as 450 °C. The amorphous-like Ta-Al alloy is stable up to 550 °C, but then exhibits polycrystalline multiphase formation at 650 °C. The resistivity of Ta-Al films is also related to the annealing temperature. The resistivity of Ta-rich Ta-Al film increases to about 13.5% from as-deposited to after annealing at 450 °C while that is doubled in the Al-rich Ta-Al film. In contrast, the resistivity of the amorphous-like Ta-Al film increased by about 6.1% at 450 °C and then remains nearly stable at 1.5% variation on annealing at 450-550 °C. The as-deposited amorphous-like Ta-Al film has the merits of high resistivity, smooth morphology and good thermal stability at annealing temperatures of up to 550 °C. These attributes are beneficial for the thermal bubble inkjet application with thermal cycling at maximum temperatures below 400 °C.     

Soft magnetic properties of carbide-dispersed nanocrystalline films with high thermal stability

Nanocrystalline Fe-M-C, Co-M-C, and Ni-M-C (M = group IVa-VIa metals) films in which extremely fine M-carbide particles are dispersed were prepared by annealing sputter-deposited amorphous alloy films. Of these films, the Fe-M-C and Co-M-C films exhibited good soft magnetic properties. These soft magnetic properties were maintained after annealing at elevated temperatures, because carbide particles dispersed in the films considerably retard the grain growth of Fe-rich or Co-rich nanocrystallites. Films containing Ta or Hf exhibit particularly high thermal stability (around 1000 K). On the other hand, Zr and Hf are suitable for obtaining high saturation magnetization,Is, because the amount of these elements needed for amorphization is less than other M elements. The highest Is of films containing Zr or Hf was 1.7 T for Fe-M-C and 1.6 T for Co-M-C films. Because the magnetostriction of Fe-M-C films is dominated primarily by the C concentration dissolved into Fe, zero-magnetostrictive films can easily be attained by controlling the C to M ratio or annealing conditions. In addition to the good performance of Fe-Hf-C films, a higherIs value of 2.0 T was achieved by multilayering the Fe-Hf-C with Fe, and improved frequency characteristics of permeability as well as higher thermal stability by about 100 K was achieved by Si additions without sacrificing other properties. These carbide-dispersed nanocrystalline films are suitable for use in high-density magnetic recording heads fabricated by glass bonding processes.     

沉积和退火温度对多晶ZnO薄膜结构特性的影响

采用RF反应溅射法在Si（111）衬底上制备出了沿C轴高度取向的多晶ZnO薄膜。通过对ZnO薄膜的X射线衍射（XRD）分析,研究了沉积温度及退火对多晶ZnO薄膜取向性、晶粒大小和应力的影响。结果表明,衬底温度和退火温度对多晶ZnO薄膜的晶体结构影响显著。适当的提高衬底温度或适当的增加退火温度都能有效地改善ZnO薄膜的结构特性,但增加退火温度更有优势。同时原子力显微镜观察表明,退火能有效地降低ZnO薄膜的表面粗糙程度。     

Alloys Preparation of Ag Particles/Islands on Si Wafer by RF Magnetron Sputtering

In order to investigate the morphology change of Ag nano-particles/island film with the sputtering time and annealing temperature,Ag nano-particles/island films were sputtered on the silicon wafers by radio-frequency(RF)magnetron sputtering.Ag nano-particles/islands films were sputtered on Si wafer with different time.After sputtering,the samples with Ag nano-particles/islands films were annealed at 100,200 and 400 o C for 1 h,respectively.Raman spectrum was employed to examine the phase stability of Ag particles/island film after annealed at 400 o C for 1h.The result showed that the Raman spectrum peak of Ag particles/island film with annealed at 400 o C was similar to that of pure Ag.Scanning electron microscope(SEM)was used to test the microstructures and morphology of the films with different condition.To further study the morphology change,atomic force microscope(AFM)was used to test surface morphology of the Ag particles/islands films.The SEM and AFM results showed that the morphology of Ag nano-particles/island films were different with the increasing sputtering time.Ag particles went through a dramatic change on the Si wafer surface,when sputtering time changed from 3 to 60 s,Ag particles diffused and agglomerated with the annealing temperature increasing.     

Influence of annealing on the structural and optical properties of ZnO films grown by MOCVD

The properties of ZnO films grown on Si (1 1 1) substrates by Metal-Organic Chemical Vapor Deposition technique using diethylzinc and H₂O as reactant gases are reported. The primary focus is on understanding the origin of deep-level luminescence. As increasing the annealing temperature, a visible emission is observed both in samples annealing in oxygen atmosphere and nitrogen atmosphere. In addition, this broad defect emission becomes obviously asymmetric when the annealing temperature was increased to 1000 °C in oxygen atmosphere. Theoretical investigations have reported that the formation enthalpy of defects is varied under different conditions. With these results, it is suggested that the visible emission in ZnO films annealed in oxygen atmosphere is related to zinc vacancy and oxygen interstitial defects. While, the green emission in ZnO films which were annealed in nitrogen atmosphere is attributed to oxygen vacancy defects.     

纳米晶Fe_（73．5）Cu_1Nb_3Si_（13．5）B_9合金中缺陷及内应力的分布研究

用正电子湮没技术和微观磁学方法研究了纳米晶Ｆｅ_（７３．５）Ｃｕ_（１）Ｎｂ_（３）Ｓｉ_（１３．３）Ｂ_９合金结构缺陷在退火过程中的变化规律，表明晶化初期形成的界面结构只引入少量的缺陷，晶化后期由于出现大量晶界，缺陷浓度急剧上升；非晶制备过程中以及晶化时引入的准位错偶极子造成的应力场对其软磁性能有很大的影响，并可以解释在最佳退火温度的磁性行为。     

退火对栅介质SrHfON薄膜性能的影响

采用射频磁控溅射法在Si衬底上制备新型栅介质SrHfON薄膜。采用X射线衍射(XRD)仪、高分辨透射电镜(HRTEM)和X射线光电子谱(XPS)分析退火对SrHfON薄膜的界面形态、薄膜的结构和电学性能的影响。结果表明,SrHfON薄膜经900℃退火后仍保持非晶态,表现出良好的热稳定性。SrHfON薄膜与Si衬底的界面主要由HfSixOy和SiO2组成。以SrHfON薄膜为栅介质的MOS电容结构具有较小的漏电流密度,并且漏电流密度随着退火温度的升高而减小。在外加偏压(Vg)为+1V时样品在沉积态和900℃退火后的漏电流密度分别为4.3×10-6和1.2×10-7A/cm2。研究表明,SrHfON薄膜是一种很有希望替代SiO2的新型栅介质材料。     

Effects of annealing temperature and time on microstructure and magnetic properties of Pr-Co thin films

A series of Pr-Co thin films were deposited on the Si (100) substrates with Cr underlayer by magnetron sputtering. The effects of both the post-annealing temperature and the annealing time on the microstructure and magnetic properties for the Pr-Co films were studied systemati- cally. The as-deposited Pr-Co thin films are mostly amorphous and tend to crystallize after annealing at temperatures above 600 C. When the annealing time is increased, the films show a complicated structure with various phases coexisting. Accordingly, the as-deposited film and low temperature annealed films are soft magnets and films annealed at temperatures beyond 600 C tend to be hard magnets. When the annealing time is increased from 5 min to 2 h, the films transfer from hard magnets to soft again. The sample annealed at 600 C for 10 min shows the largest coercivity of 0.59 T.     

Characterization of NiCo composite silicides by 10 nm-Ni50Co50 alloy films with additional annealing

We fabricated 10 nm-Ni₅₀Co₅₀ alloy films into a single crystal and a polycrystalline silicon substrate, and applied silicidation annealing to these substrates at 600 °C to 1100 °C for 40 s. To test the thermal stability of the processed silicide layers, we examined the change in their physical properties after an additional 30-min annealing at the given rapid thermal annealing (RTA) temperatures. To characterize the physical properties of the silicide layers, we used a four-point probe, an x-ray diffractometer (XRD), a transmission electron microscope, a scanning electron microscope, an Auger electron spectroscope, and an atomic force microscope. The silicide layer formed only through RTA showed low resistance (20 Ω/sq) at up to 1100 °C and 900 °C for the single crystal and for the polycrystalline silicon substrate, respectively. Sheet resistance after the additional 30-min annealing was low, and did not differ significantly before and after the additional annealing for the single crystal substrate, but it became high at all temperatures for the polycrystalline substrate. The XRD confirmed the formation of the NiSi (or Ni(Co)Si) phase, in which there were no changes after the additional annealing. The thickness of the RTA-formed silicide layers varied from 11 nm to 13 nm, 20 nm and 28 nm, depending on whether the temperature was 700 °C or 1000 °C, for both the single and the polycrystalline substrates. The thickness of the silicide layers tended to increase from 22 nm to 25 nm, 48 nm and 82 nm after the additional 30-min annealing. Auger depth profiling also confirmed changes in thickness with the additional annealing. The surface roughness was no greater than 10 nm in all cases, even with the additional annealing. We verified that the nano-silicide layer formed with the proposed nano-NiCo alloy films satisfied the requirements for the nano-CMOS process.     

60Si2Mn化学氧化的机理分析与工艺改进研究

目的 解决60Si2 Mn合金钢在化学氧化时生成的化学氧化膜颜色差异问题.方法 采用辉光放电光谱(GDS)分析不同氧化温度下制备的60Si2Mn化学氧化膜层成分及化学氧化膜的厚度,采用扫描电镜(SEM)观测氧化膜表面形貌,分析合金元素对化学氧化的影响,以及化学氧化温度对化学氧化膜厚度、成分含量及颜色的影响,改进60Si2 Mn化学氧化工艺.结果 不同化学氧化温度对60Si2 Mn化学氧化膜厚度及膜层中合金成分的含量有较大影响.不同化学氧化温度导致化学氧化膜厚度差异,化学氧化膜中合金成分Si、Mn氧化物含量差异导致60 Si2 Mn化学氧化膜颜色的差异.结论 相对于普通钢,化学氧化温度为(142±1)℃时,可以保证化学氧化膜厚度及Fe3O4含量的稳定,进而有效确保氧化膜的颜色一致性.     

基于稳定固溶体团簇模型的含氮铜合金薄膜

目的制备结构和性能稳定的含氮铜合金薄膜,提高铜合金的硬度。方法基于稳定固溶体团簇模型在Cu-Ni基合金成分设计方面的研究,进一步利用Nb与N相对较大的负混合焓以及Ni的作用,将N带入Cu中,达到稳定N的目的。采用磁控溅射方法在N2/Ar比为1/30的气氛中制备了Si(100)基Cu-Ni-Nb-N四元合金薄膜和参比样品,并通过电子探针、X射线衍射仪和透射电子显微镜分别分析了薄膜的成分、结构和膜-基界面,采用双电测四探针测量仪和超轻微载荷努氏硬度计测量了薄膜的电阻率和硬度。结果与Cu(N)薄膜相比,四元合金薄膜具有更好的结构稳定性和更高的硬度。溅射态时,四元薄膜由铜的纳米柱状晶和少量NbN组成,硬度均在5 GPa左右。550℃/1 h退火后,薄膜致密度好,部分N能以NbN化合物的形式稳定存在于薄膜中,大部分薄膜的硬度在3 GPa以上,并且具有较好的导电性。结论采用稳定固溶体团簇模型选择固氮元素,能够制备出综合性能较好的含氮铜合金薄膜,为其进一步用于铜及其合金的表面改性奠定了基础。     

电弧离子镀法制备高硬度Cr-Si-C-N薄膜

采用电弧离子反应沉积技术在SCM415渗碳淬火钢基片上沉积了Cr-Si-C-N薄膜,三甲基硅烷(TMS)反应气体作为Si和C掺杂源,通过改变TMS流量实现了薄膜中si和C含量的调节.利用XPS,XRD,HRTEM和显微硬度计研究了Cr-Si-C-N薄膜的化学状态、显微组织和显微硬度.Cr-Si-C-N薄膜中的Si和C含量随TMS流量的增加而单调增加.在TMS流鼍小于:90 mL/min时,薄膜中Si和C含量较少,薄膜由Cr(C,N)纳米晶与Si_3N_4非品(nc-Cr(C,N)/a-Si_3N_4)组成,薄膜硬度随流量的增加而单调增大,最大至4500 HK.硬度的增加源于固溶强化及薄膜中纳米晶/非晶复合结构的形成;当TMS流量大于90 mL/min时,薄膜中Si和C含量较多,多余的C以游离态形式存在,且随TMS流量的增加而增多,薄膜硬度下降.     

ATOMIC SCALE MECHANISM OF RESTRAINED EMBRITTLEMENT IN AMORPHOUS Fe_(78)B_(13)Si_9 ALLOY BY ELECTRIC PULSE RAPID ANNEALING

1.IntroductionTheiron-basedamorphousalloysproducedviarapidquenchingtechniquepossessgoodmechanicalproperties.However,toacquiredesirablesoftmagneticproperties,alongperiodofconventionalfurnaceannealing(CFA)(1-2h)isrequired.Unfortunately,theannealingembrittlementoccursinevitablytocreatemanydifficultiesinpractice.Flashannealingorelectricpulserapidannealing(EPRA)isbasedonthejouleheatingeffectsofatransientcurrentpulseflowinginanamorphousribbon.RecentlyithasbeenprovedthatEPRAisasuitablemethodfori…     

Improvement of deformation capacity of gas-atomized hypereutectic Al-Si alloy powder by annealing treatment

Gas-atomized pure metal or alloy powders are widely used as raw material in the preparation of high performance materials by powder metallurgy route (compaction and sintering). However, cold compactibility of gas-atomized Al-Si alloy powder is inhibited due to the high strength as a result of the refined Si phases and the supersaturated Al matrix. The effect of annealing on improving the compactibility of Al-Si alloy powder was studied. The densification was investigated by the HECKEL compaction equation in terms of deformation capacity. Moreover, the microstructures and bending fracture surfaces of the green compacts were examined to clarify the densification behavior. The results show that a maximum relative density of 96.1% is obtained when the powder is annealed at 400 °C. The deformation capacity is significantly improved by annealing treatment due to the softening of Al matrix, precipitation of supersaturated Si phases, dissolution of needle-like eutectic phase, and spheroidization of Si phases.