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1.
利用直流热阴极辉光放电方法制备出了高品质金刚石厚膜,生长速率达到20μm/h,生长厚度达到3mm.为了解其工作特性、优化沉积工艺,本文研究了放电电压对金刚石沉积速率和品质的影响.通过对扫描电镜、拉曼谱和XRD图谱分析得出,随着放电电压的增加,沉积速率呈下降趋势,电压在850~950V范围金刚石中石墨和非晶碳明显减少,晶粒均匀,表面晶向以(110)为主,金刚石薄膜的质量显著提高.  相似文献   

2.
在自行研制的直流电弧等离子喷射化学气相金刚石膜设备上,初步研究了衬底温度、甲烷浓度、输入功率和循环气量等工艺参数对沉积金刚石膜的影响.总结出了制备各种级别金刚石膜的一般规律.并以11μm/h的沉积速率制备了直径60mm、厚度均匀的高质量自支撑金刚石膜,热导率可达18W/cm·K,厚度为0.7mm,其热导率已接近天然金刚石.  相似文献   

3.
大面积无衬底自支撑金刚石厚膜沉积   总被引:6,自引:1,他引:5  
讨论了在采用直流电弧等离子体喷射CVD工艺沉积大面积无衬底自支撑金刚石厚膜时遇到的若干技术问题,在制备过程中经常出现的膜炸裂现象,主要是由于膜和衬底材料线膨胀系数差异引起的巨大热应力,而衬底表面状态的控制、沉积过程中工艺参数的优化和控制也是一个重要的因素,因此,必须对整个金刚石厚膜沉积过程进行严格而系统的控制,团能有效地保证获得无裂纹大面积金刚石自支撑厚膜。  相似文献   

4.
采用灯丝热解化学气相沉积方法,在不同的碳源气体气氛中合成金刚石薄膜,并研究不同工艺条件下的金刚石膜生长速率.结果表明,在较低的灯丝分解气体温度和较近的灯丝与衬底距离条件下,以丙酮为碳源气体合成的金刚石膜具有较高的生长速率和较好的质量.  相似文献   

5.
为制备高质量的声表面波器件,探索金刚石薄膜的沉积工艺,采用直流电弧等离子体喷射化学气相沉积技术和特殊的复合衬底技术,在单晶硅衬底上制备了大面积、高质量的金刚石薄膜,成功解决了单晶硅衬底在沉积金刚石薄膜过程中产生的变形问题.研究了甲烷浓度和沉积温度对金刚石薄膜质量的影响,优化了沉积工艺.结果表明,甲烷气体体积分数为1.8%时,晶粒最为细小,同时金刚石薄膜的表面粗糙度最小,表面最为光滑.衬底温度为1000℃时生长的金刚石薄膜的晶粒尺寸较小.  相似文献   

6.
本文介绍了在863新材料领域资助下最新研制成功的100kw级高功率直流等离子体喷射(DCPlasmaJet)金刚石膜沉积系统。利用该系统在氩气—氢气—甲烷气体系中进行了初步的工艺试验,经过40小时的连续运行,在Φ110mm的基片上沉积出中心厚1.9mm,边沿厚1.6mm的金刚石膜。平均生长速率达44μm/h。  相似文献   

7.
采用显微拉曼光谱仪对直径为25.4 mm、总厚度为3.2 mm的刀具用金刚石复合片(PDC)层表面和侧面不同位置的残余应力进行测试,获得PDC金刚石层表面径向及侧面的应力分布。然后,用电火花切掉PDC的硬质合金基体,再测定金刚石层表面的拉曼光谱,从而得出金刚石层的微观残余应力。研究结果表明:PDC表面中间部分的应力为压缩应力,最大值约600 MPa,从中心到边缘逐渐降低,在离边缘2 mm左右变为拉应力;边沿拉应力的产生是基体的厚度较小,PDC朝金刚石层方向弯曲造成的;金刚石层侧面的应力为拉应力,最大值达580 MPa,位置靠近PDC界面,这是PDC出现金刚石脱层的主要原因之一;实验测得的PDC微观应力为62.5 MPa。  相似文献   

8.
PECVD法在聚酰亚胺上沉积氮化硅薄膜的工艺研究   总被引:3,自引:0,他引:3  
采用了等离子体增强化学气相沉积法(Plasma-Enhanced Chemical Vapor Deposition,PECVD)在聚酰亚胺(Polyimide,PI)牺牲层上生长氮化硅薄膜;利用微旋转结构测量氮化硅薄膜的残余应力;讨论沉积温度、射频功率、反应气体流量比等工艺参数对氮化硅薄膜的残余应力的影响,并把薄膜的残余应力分为热应力和本征应力加以分析,得出适合制作射频MEMS开关器件中的桥式梁的氮化硅薄膜的最佳工艺条件。  相似文献   

9.
采用电子束沉积的方法,分别在K9玻璃基片上制备了LaF3单层膜.研究了基板温度对LaF3薄膜残余应力的影响;基板温度从200 ℃上升到350℃,间隔为50℃.利用ZYGO干涉仪测量了基板镀膜前后的面型变化,利用Stoney公式计算出残余应力;分析结果表明:在本实验条件下,残余应力为张应力,随基板温度的增加,有增大的趋势.  相似文献   

10.
MEMS开关中氮化硅薄膜工艺研究   总被引:1,自引:0,他引:1       下载免费PDF全文
分析了沉积薄膜厚度、PECVD的薄膜沉积温度、反应气体形成的杂质以及多层薄膜之间热应力匹配等因素对薄膜残余应力的影响.应用光刻分割聚酰亚胺(PI)牺牲层、分层生长氮化硅薄膜及快速热退火等工艺减小薄膜残余应力,成功生长出了合格的氮化硅薄膜.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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