退火对SOI材料电阻率的影响

在SIMOX SOI材料外延生长硅层时,存在电阻率较高的过渡层.对衬底研究表明,SOI层呈现高阻.采取不同温度对衬底进行退火,结果表明:合适的温度退火可以明显降低SOI层电阻率,对外延硅层后的SOI材料进行退火,也可以部分降低外延层电阻率,减少外延层中高阻层厚度.     

PIN、NBP及NBN型InAsSb中波红外探测器光电性能研究

系统探索了GaSb(001)衬底上InAsSb体材料的分子束外延生长和PIN型、NBP型及NBN型InAsSb单元单色红外探测器的制备工艺,并对其光学、电学等相关物理特性进行了研究对比.PIN型InAsSb单元探测器的R0A为224Ω·cm2(100K),77K下峰值探测率为3.6×1010cmHz1/2/W.NBN型和NBP型InAsSb单元探测器的R0A都达到了105Ω·cm2(100K)的量级,但NBN型比NBP型的R0A值更大,暗电流密度更低,77K下峰值探测率分别为8.5×101 2cmHz1/2/W和2.4×108cmHz1/2/W.最后制备完成了50%截止波长为3.8μm(PIN型)、3.4μm(NBP型)、2.6μm(NBN型)的InAsSb单元探测器.     

硅纳米图形诱导生长分布均匀的锗纳米岛

采用阳极氧化铝模板的方法在硅衬底上制备出分布均匀的硅纳米图形,研究了在硅纳米图形衬底上自组装生长锗纳米岛的演化.发现在500℃下,硅纳米图形对自组装生长锗岛起到诱导作用,获得尺寸和分布均匀的Ge纳米岛,岛的尺寸为35nm,密度达到5×1010 cm-2.当温度较低和较高时,硅纳米图形的诱导作用变得不明显.最后探讨了纳米图形诱导锗纳米岛生长可能的机理.     

面向GPON的硅基锗探测器应用研究

锗硅探测器由于其在近红外波段有高响应度、高带宽,且与CMOS(Complementary Metal Oxide Semiconductor)工艺兼容等优良的光电特性,已经成为近几年的研究热点之一.为了研究硅基锗APD的商用通信测试指标,结合GPON(Gigabit-capable Passive Optical Networks)接入网的技术指标要求,实验研究了硅基锗探测器的光电变换特性.采用BERT搭建了可靠的硅基锗探测器测试系统,并对探测器进行了性能测试.该设计方案可靠性高,测试数据对实际应用有一定的指导意义.测试眼图表明,该探测器可以在2.5Gbps速率下可靠检测出2电平调制符号,有在GPON光通信网络中应用的潜力.讨论了进一步降低误码率,实现低误码、高可靠性的数据通信,减小信号因内部逻辑设计而产生的误码的几种方法.其中包括采用可扩展的Aurora光纤传输协议的传输方案、集成直流平衡缓冲器(DC-balancing Buffer)的方法和加入CDR(时钟数据恢复)模块的方法.数据表明,所提出的测试方案是可行的.本试验为硅基锗探测器在GPON上应用提供可行解决方案和技术数据.     

辉光放电无定形锗硅合金膜的红外吸收和氧的扩散

本工作主要着眼于锗硅合金(Si_(1-x) Ge_x∶H)红外吸收谱的某些变化和生长参数的关系,以寻求较合适的生长条件.实验中改变的参数有三个:锗含量,衬底温度,射频功率.我们首次观察到空气中的氧能扩散进某些条件下生长的锗硅合金膜.样品的制备和测量所用无定形锗硅合金膜,是在射频辉光放电中分解一定体积比的硅烷(SiH_4)和锗烷(GeH_4)淀积而成.硅烷、锗烷的纯度为99.999%,水和氧的含量都少于五百万分之一.红外测量的样品是淀积在粗抛过的高阻硅单晶片上.用涡旋分子泵把真空室抽空至真空度高于3×10~(-8)乇,然后通进硅烷和锗烷,按所要求的体积比进行混和,并把总压力固定在0.25乇.锗的含量x 在0和0.75之间变化,衬底温度在228—     

SiGe合金氧化层中的纳米结构

我们在硅锗合金衬底上采用氧化等制膜方式生成零维和三维的纳米结构样品,用高精度椭偏仪(HPE)、卢瑟福背散射谱仪(RBS)和高分辨率扫描透射电子显微镜(HR-STEM)测量样品的纳米结构,并采用美国威思康新州立大学开发的Rump模拟软件对卢瑟福背散射谱(RBS)中的CHANNEL谱和RANDOM谱分别进行精细结构模拟,计算且测量出纳米氧化层与锗的纳米薄膜结构分布,并且反馈控制加工过程,优化硅锗半导体材料纳米结构样品的加工条件.我们在硅锗合金的氧化层表面中首次发现纳米锗量子点和量子层结构,我们首次提出的生成硅锗纳米结构的优化加工条件的氧化时间和氧化温度的匹配公式和理论模型与实验结果拟合得很好.     

MECHANISM OF NANOSTRUCTURE IN OXIDATION OF Si1-xGex AL-LOYS

我们在硅锗合金衬底上采用氧化等制膜方式生成零维和三维的纳米结构样品,用高精度椭偏仪(HPE)、卢瑟福背散射谱仪(RBS)和高分辨率扫描透射电子显微镜(HR-STEM)测量样品的纳米结构,并采用美国威思康新州立大学开发的Rump模拟软件对卢瑟福背散射谱(RBS)中的CHANNEL谱和RANDOM谱分别进行精细结构模拟,计算且测量出纳米氧化层与锗的纳米薄膜结构分布,并且反馈控制加工过程,优化硅锗半导体材料纳米结构样品的加工条件.我们在硅锗合金的氧化层表面中首次发现纳米锗量子点和量子层结构,我们首次提出的生成硅锗纳米结构的优化加工条件的氧化时间和氧化温度的匹配公式和理论模型与实验结果拟合得很好.     

脉冲激光作用硅锗合金形成多种捕获界面态

用脉冲激光辐照和退火氧化处理在硅锗合金衬底上形成了具有不同界面态分布的氧化低维结构.在这些结构中都有在几个纳米的氧化层中约束了大量的硅和锗的纳米团簇结构,分析这些低维结构所产生的光致荧光(PL)光谱发现,由于氧化条件的不同所生成的这些结构对应的PL光谱无论是强度,还是频率都发生了显著的变化.用量子受限-硅锗与氧化物界面态综合模型解释了样品PL发光的变化.     

SOI双槽隔离结构的耐压特性

理论推导了绝缘体上硅(SOI)双槽隔离结构的耐压模型.该模型表明,在SOI双槽隔离结构中,因隔离氧化层压降的不均衡,高压侧隔离氧化层提前发生介质击穿,从而导致SOI双槽隔离结构的临界击穿电压小于理论值.增大沟槽纵横比和减小槽间距可以减弱隔离氧化层上压降的不均衡性,提高SOI双槽隔离结构的临界击穿电压.Sentaurus器件仿真软件的模拟结果和华润上华半导体有限公司0.5μm 200 V SOI工艺平台下的流片测试结果均证明,减小槽间距和增大沟槽纵横比是提高双槽隔离结构临界击穿电压的有效方法,同时也证明了该耐压模型的正确性.     

硅,锗衬底上的软硬碳氢膜

我们使用射频-直流辉光放电系统制备了非晶碳氢膜(a-C:H),所用的衬底为半导体级抛光后的硅、锗单晶片,锗片纯度在9个9以上,硅片为N型,电阻率10～20Ω·cm为研究淀积源对膜层结构的影响,我们除使用气态源乙炔(C_2H_2)外,还使用了液态源戌烷(C_5H_(12))。所用淀积参数为:高频频率10MHz,高频功率密度1.4～2.8W/cm~2(未能精确测量),直流偏压0～600V,气体流量0.3～0.61/min,反应室内压强0.01～1托,衬底温度:室温～300℃。     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.