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 共查询到19条相似文献,搜索用时 640 毫秒
1.
氮化硼薄膜的脉冲激光沉积   总被引:3,自引:0,他引:3  
用Q开关YAG激光器的1.06μm的脉冲激光在硅及玻璃衬底上沉积了氮化硼薄膜。做了SEM,XRD,红外透射谱和紫外一可见透射谱等测试。确认为六方氮化硼(h-BN)薄膜.并测出其禁带宽度、晶格常数等。  相似文献   

2.
沉积温度对Ti—B—N复合薄膜微结构及力学性能的影响   总被引:1,自引:0,他引:1  
采用多靶轮流溅射技术,用Ti和六方氮化硼(h-BN)反应合成了Ti-B-N薄膜,采用XRD、TEM和显微硬度计研究了薄膜的微结构及其力学性能。结果表明,室温下沉积的Ti-B-N薄膜为非晶体的Ti(N,B)化合物,其硬度达到HK2470;高温下沉积的薄膜为TiN结构类型的Ti(N,B)晶体,薄膜在晶化后硬度略有降低。  相似文献   

3.
我们采用低温等离子体CVD技术在金属表面成功地淀积了BN-SiN复合陶瓷薄膜。并用BF-1型薄膜附着力测定仪测试了它的结合力,以及用俄歇电子能谱(AES)分析其成键状态。结果表明:这种薄膜与基体之间具有较强的Fe-B键结合力。  相似文献   

4.
郑永梅 《半导体学报》1996,17(12):881-885
本文采用Lowdin微扰原理改进计算效率的局域密度泛函(LDF)线性Muffin-tin轨道原子球近似(LMTO-ASA)能带从头计算方法,以平均键能Em作参考能级,计算了以闪锌矿结构氯化硼为衬底外延生长金刚石(C/BN)、以C0.5(BN)0.5合金为衬底外延生长金刚石与闪锌矿结构氯化硼(CIBN)、以金刚石为衬底外延生长闪锌矿结构氯化硼(C\BN)和金刚石与氮化硼以平均晶格常数匹配生长(C-BN)等四种不同情况下,宽禁带半导体异质结C/BN的价带偏移△Ev值,结果分别为1.505、1.494、1.38  相似文献   

5.
本文对热灯丝(热电子)辅助射频等离子体CVD法制备的立方氮化硼(c-BN)薄膜进行了研究。实验结果表明,c-BN膜的质量与膜沉积条件有密切的关系。并对其结果作了简要讨论。  相似文献   

6.
多层结构铁电薄膜的I—V特性性能的研究   总被引:3,自引:0,他引:3  
为FRAM、FFET和FDM的实际应用研究,提出了多层结构铁电薄膜的设计思想,实际制备了M/BIT/p-Si、M/PZT/BIT/p-Si、M/BIT/PZT/BIT/p-Si三种结构铁电薄膜,并测量了它们的I-V特性曲线。结果表明,夹层结构铁电薄膜M/BIT/PZT/BIT/p-Si漏电流密度J最小,在500nm厚时J+(+3V)约2.8×10-10A/mm2,J-(-3V)约1.2×10-12A/mm2优于单层和双层结构铁电薄膜的结果。  相似文献   

7.
爱立信(ERICSSON) 输入(右*左*左*左*)后会显示: ABCDEF GHIJ PRGXXXXXXXXX ABCDEF为年、月、日(YY/MM/DD) 诺基亚(NOKIA) 输入*#000#显示: VXX·XX为软件版本, DD-MM-YY为生产日期(日-月-年), NXX-X为手机型号:如3310为NHM-5。 摩托罗拉( MOTOROLA) 查MSN(在手机标贴上)内容,MSN长度为十位: AAA-B-CC-DDDD AAA为型号代码(A74- Cd920/928, A84 2000); B为产地代码(2-…  相似文献   

8.
脉冲激光沉积铌酸锶钡铁电薄膜及其性能表征   总被引:3,自引:0,他引:3  
利用脉冲激光沉积(PLD)技术在MgO、LSCO/MgO衬底上在位制备了铌酸锶钡(SBN)铁电薄膜,发现SBN薄膜在MgO、LSCO/MgO衬底上均呈(001)择优取向。用扫描电子显微镜(SEM)和原子力显微镜(AFM)表明SBN薄膜的晶粒细小致密,铁电微畴尺寸约为200nm。SBN薄膜的剩余极化强度为18.6μC/cm2,矫顽场为22.3kV/cm。  相似文献   

9.
CdS多晶薄膜的电学性质   总被引:9,自引:1,他引:8  
黄小融 《半导体光电》1998,19(6):404-406,411
用化学池沉积方法(CBD)制备了CdS多晶薄膜,并对薄膜进行了退火处理,测量了不同CdS薄膜光电导、暗电导和电导-温度关系,计算了电导激光活能。结果表明:刚沉积的CdS暗电导率为10^-6Ω^-1.cm^-1比光电导率低二个数量级,退火后,电导升高,电导激活能减小。X射线衍射分析表明,经退火后,CdS薄膜发生相变,由立方结构变成六方结构。对上述结果进行了讨论。  相似文献   

10.
B-ISDN与N-ISDN的区别B-ISDN与N-ISDN相比,主要有以下3点不同,这也是B-ISDN的优势:(l)以光纤为传输媒介。N-ISDN是建立在原有电话网、分组网基础上的,它可利用现有网络终端、用户环路等网络资源。而8-1犯N则必须以光纤作...  相似文献   

11.
The various crystallographic forms of boron nitride (BN) are of great technological interest because of their demonstrated tribological, high-temperature, thermally conducting, electrically insulating, and wide-bandgap semiconductor properties. Unfortunately, the synthesis of crystalline BN films is still in the early stages of development. Furthermore, although polycrystalline BN films have been prepared by a variety of physical and chemical vapor deposition techniques, the capability does not currently exist for depositing large area single-crystal or oriented films of BN. Such single-crystal films are required for many applications of interest, especially in electronics. The present paper reports on a new approach to the oriented growth of boron nitride using a novel molten layer epitaxy technique. Well-oriented hexagonal boron nitride (h-BN) crystals were obtained with highly faceted crystal shapes. The h-BN was formed via precipitation from a molten, hydrogen-saturated Ni surface layer. Solid cubic BN was utilized as the source material and was dissolved into the substrate surface during a brief high-temperature anneal. It was found that surface melting occurred during this process and the B diffused into the Ni substrate, whereas the N was expelled into the growth chamber. Oriented BN was then precipitated as the surface layer was allowed to resolidify.  相似文献   

12.
湿化学法合成先驱体制备氮化硼纤维的研究   总被引:3,自引:0,他引:3  
以硼酸和三聚氰胺为原料,采用湿化学法合成先驱体,在氮气气氛中制备出氮化硼(BN)纤维。用中和滴定法、红外吸收光谱(IR)、X射线衍射(XRD)、扫描电镜(SEM)对合成的先驱体及制得的BN纤维的氮含量、形貌及结构进行分析。结果表明合成温度1,700℃,保温时间3 h,氮气流量2 L/min时制得的BN纤维的氮含量为53.46%,达到理论值的95%。先驱体分子中存在B—N、N—H、C—O—C、—(B—N)—结构单元。用扫描电镜观察制得的BN纤维直径为2~10 靘,长径比为40~50。  相似文献   

13.
The electronic and transport properties of embedded boron nitride(BN) nanodot superlattices of armchair graphene nanoribbons are studied by first-principles calculations.The band structure of the graphene superlattice strongly depends on the geometric shape and size of the BN nanodot,as well as the concentration of nanodots.The conduction bands and valence bands near the Fermi level are nearly symmetric,which is induced by electron-hole symmetry.When B and N atoms in the graphene superlattices with a triangular BN nanodot are exchanged,the valance bands and conduction bands are inverted with respect to the Fermi level due to electron-hole symmetry.In addition,the hybridization ofπorbitals from C and redundant B atoms or N atoms leads to a localized band appearing near the Fermi level.Our results also show a series of resonant peaks appearing in the conductance.This strongly depends on the distance of the two BN nanodots and on the shape of the BN nanodot. Controlling these parameters might allow the modulation of the electronic response of the systems.  相似文献   

14.
利用离子束辅助沉积技术在金刚石薄膜衬底上制备立方氮化硼薄膜,傅立叶变换红外谱的结果表明,在高度(001)织构金刚石薄膜衬底上沉积的立方氮化硼薄膜是纯的立方相,而在多晶金刚石薄膜衬底上制备的立方氮化硼薄膜中还含少量的六角氮化硼。高分辨透射电镜的分析表明,在金刚石晶粒上异质外延的c-BN直接成核于金刚石衬底,界面没有六角氮化硼过渡层;而在含有大量缺陷的晶粒边界,存在六角氮化硼的成核与生长。  相似文献   

15.
Applications of SiH-free silicon nitride (SiN) films, formed by tetrachlorosilane (TCS) and ammonia, have been proved to effectively suppress the SiN-induced boron penetration. The SiN-induced boron penetration has been investigated in detail by using boron-doped polysilicon gated capacitors with several kinds of thick SiN films. It was clarified for the first time that the SiN-induced boron penetration becomes worse with SiH content in SiN films and deposition technique of SiH-free TCS-SiN films is essential for realization of the high-performance PMOSFETs  相似文献   

16.
采用射频(RF)磁控溅射的方法,通过改变工艺参数在n型Si(100)片上制备六方氮化硼(h-BN)薄膜。通过傅立叶红外(FTIR)光谱仪,X射线衍射(XRD)仪进行结构表征,原子力显微镜(AFM)进行表面形貌和压电性能表征。测试结果表明,在射频功率为300 W、衬底温度为500℃、工作压强在0.8Pa、N2与Ar流量比为4∶20和衬底偏压在-200V时制备的六方BN薄膜具有高纯度、高c-轴择优取向,颗粒均匀致密,粗糙度为2.26nm,具有压电性并且压电响应均匀,符合高频声表面波器件基片高声速、优压电性要求。薄膜压电性测试研究表明,AFM的PFM测试方法适用于纳米结构半导体薄膜的压电性及其压电响应分布特性的表征。  相似文献   

17.
BxGa1−xN films were deposited on 6H-SiC (0001) substrates at 1000°C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. The presence of boron was detected by Auger scanning microprobe, the shift of the (00.2) x-ray diffraction peak, and low-temperature photoluminescence. A single-phase BxGa1−xN alloy with x=1.5% was produced at the gas phase B/Ga ratio of 0.005. Phase separation into wurtzite BGaN and the B-rich phase occurred for a B/Ga ratio in the 0.01–0.2 range. Only BN was formed for B/Ga >0.2. The B-rich phase was identified as h-BN with sp2 bonding based on the results of Fourier transform infrared spectroscopy. As the diborane flow exceeds the threshold concentration, the growth rate of BGaN decreases sharply, because the growth of GaN is poisoned by the formation of the slow growing BN phase. The bandedge emission of BxGa1−xN varies from 3.451 eV for x=0% with FWHM of 39.2 meV to 3.465 eV for x=1.5% with FWHM of 35.1 meV. The narrower FWHM indicates that the quality of GaN epilayer is improved with a small amount of boron incorporation. The PL linewidths become broader as more boron is introduced into the solid solution.  相似文献   

18.
The synthesis and characterization of multifunctional cement and concrete composites filled with hexagonal boron nitride (h‐BN) and graphite oxide (GO), is reported and their superior mechanical strength and oil adsorption properties compared to composites devoid of fillers are illustrated. GO is utilized to bridge the cement surfaces while h‐BN is used to mechanically reinforce the composites and adsorb the oil. Introduction of these fillers even at low filler weight fractions increases the compressive strength and toughness properties of pristine cement and of porous concrete significantly, while the porous composite concrete illustrates excellent ability for water separation and crude oil adsorption. Experimental results along with theoretical calculations show that such nanoengineered forms of cement based composites would enable the development of novel forms of multifunctional structural materials with a range of environmental applications.  相似文献   

19.
Novel yard‐glass shaped boron nitride nanotubes (YG‐BNNTs) periodically filled with Fe nanoparticles were synthesized by a catalytic reaction process of ammonia with boron precursors at 1300 °C. Such novel structures were extensively characterized using X‐ray diffraction and advanced electron microscopy. The Fe‐filled boron nitride nanotubes show excellent ferromagnetic properties at room temperature with superior chemical stability. A growth model is proposed for the formation of such novel BN nanostructures.  相似文献   

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