共查询到20条相似文献,搜索用时 15 毫秒
1.
Z. John Zhang Shoushan Fan Jinlin Huang Charles M. Lieber 《Journal of Electronic Materials》1996,25(1):57-61
Carbon nitride thin films were grown using an approach that combines pulsed laser deposition and atomic beam techniques. The
composition and phases of the carbon nitride materials obtained from the reaction of laser ablated carbon and atomic nitrogen
have been systematically investigated. The nitrogen composition was found to increase to a limiting value of 50% as the fluence
was decreased for laser ablation at both 532 and 248 nm. Analysis of these experiments show that the growth rate determines
the overall nitrogen composition, and thus suggests that a key step in the growth mechanism involves a surface reaction between
carbon and nitrogen. Infrared spectroscopy has also been used to assess the phases present in the carbon nitride thin films.
This spectroscopic measurement indicates that a cyanogen-like impurity occurs in films with nitrogen compositions greater
than 30%. Investigations of the effects of thermal annealing have been carried out, and show that the impurity phase can be
eliminated to yield a single phase material. In addition, systematic measurements of the electrical resistivity and thermal
conductivity of the carbon nitride films were made as a function of nitrogen content. The implications of these results are
discussed. 相似文献
2.
脉冲激光沉积法沉积类金刚石薄膜的实验研究 总被引:1,自引:0,他引:1
为了研究脉冲激光沉积法中衬底温度和距离对类金刚石薄膜的影响,首先温度保持在200℃,靶和衬底间的距离分别取25.0mm和30.0mm来沉积类金刚石膜。其次温度保持在400℃,距离分别取25.0mm和30.0mm来沉积类金刚石膜。用Raman光谱仪对薄膜的微观结构进行检测,用原子力显微镜对薄膜的表面形貌进行检测。实验结果表明:距离增加或者温度升高都会导致类金刚石薄膜的密度和sp3/ sp2的比值减小,薄膜中石墨晶粒的数量增多和体积增大。近距离时温度的变化和低温时距离的变化对薄膜微观结构产生的影响更明显。距离和温度的变化对类金刚石薄膜的表面形貌也产生显著的影响。 相似文献
3.
We have grown thin carbon films by pulsed laser deposition and have investigated the extent to which the properties of such
films, as well as the processes responsible for these properties, are laser wavelength dependent. Films were grown by ablating
material from a graphite target onto room temperature Si(100) substrates with 1064 and 248 nm laser radiation. The films were
analyzed byin situ electron energy loss spectroscopy and byex situ Raman spectroscopy. The results indicated that films grown with 1064 nm ablation were graphitic, while those grown with 248
nm radiation were diamond-like. We have also examined the mass and kinetic energy distributions of the particles ejected from
graphite by the two laser wavelengths. The results indicated that irradiation of graphite with 1064 nm laser radiation results
in the ejection of a series of carbon cluster ions C
n
+
(1 ≤ n ≤ 30) with mean kinetic energies less than 5 eV. Ablation of graphite with 248 nm radiation results in the ejection
of primarily C
2
+
and C
3
+
with mean kinetic energies of 60 and 18 eV, respectively. These results suggest that large, low energy clusters produce graphitic
films, while small, high energy clusters produce films of diamond-like carbon. 相似文献
4.
采用能量密度为1.178×109W/cm2的XeCl准分子激光直接辐照高纯度的石墨靶,并同时采用辅助放电,在1×10-5Torr的真空环境中,于温度为80℃的Si(100)的基片上淀积出类金刚石薄膜,Raman光谱显示在1330cm-1处出现较强的散射峰值;对薄膜红外光谱进行测试,其光谱在2900cm-1处有吸收峰,表明所淀积的类金刚石薄膜含有C-H键,其H元素与C元素的比为45%.薄膜的电阻率为1.89×106Ω/cm,通过光吸收测得的该薄膜的能隙为1.55eV. 相似文献
5.
简要评述了用脉冲激光沉积技术制备类金刚石膜及金刚石薄膜的研究进展,总结了激光脉冲沉积制备薄膜的基本原理及其特点,分析了激光波长,能量,衬底温度等对薄膜质量的影响。 相似文献
6.
非晶态有机聚合物薄膜脉冲激光沉积 总被引:1,自引:0,他引:1
非晶态有机聚合物薄膜具有低介电常数,高强度等优良物理特性,在微电子工业领域有着潜在应用价值而引起人们极大兴趣,本文就其沉积方法及沉积机制进行简要综述,并展望了其应用前景。 相似文献
7.
8.
脉冲激光纳米薄膜制备技术 总被引:7,自引:1,他引:6
脉冲激光薄膜沉积(PLD)是近年来受到普遍关注的制膜新技术。简要介绍了该技术的物理原理;探讨了脉冲激光沉积制膜的物理过程,激光作用的极端条件及等离子体羽辉形成的控制对薄膜成长的影响;评价了脉冲激光沉积技术在多种功能材料薄膜,特别是纳米薄膜及多层结构薄膜的制备方面的特点和优势,结合自行研制的设备,介绍了在PLD基础上发展起来的兼具分子束外延(MBE)技术特点的激光分子束外延技术(L-MBE),指出脉冲激光沉积技术在探讨激光与物理相互作用和薄膜成膜机理方面的作用,尤其是激光分子束外延技术在高质量的纳米薄膜和超晶格等人工设计薄膜的制备上显现出的巨大潜力。 相似文献
9.
10.
给出了在氧气气氛中利用单束脉冲激光交替作用锌靶和铝靶进行掺铝氧化锌(AZO)透明导电薄膜的脉冲激光沉积(PLD)新方法,分析了该方法的特点与优点,并与利用ZnO陶瓷掺杂靶制备AZO薄膜的方法进行了对比。利用该方法分别在玻璃片和硅片上制备了AZO薄膜,用SEM观察了薄膜的表面型貌,用X射线衍射谱(XRD)研究厂薄膜的结构,最后通过透射光谱分析了制备的透明导电膜在可见光区的透射性能。实验结果表明:利用该方法能够制备出性能优越的AZO功能薄膜。 相似文献
11.
用脉冲激光沉积(PLD)法在热解C制作的人工心脏机械瓣膜上沉积类金刚石(DLC)薄膜,并用3KeV的氩离子轰击(AIB)DLC薄膜。采用拉曼(Raman)光谱和X射线光电子能谱(XPS)分别对AIB前后的DLC薄膜进行检测分析,用光学显微镜观察AIB前后的DLC薄膜表面。实验结果表明:AIB不影响薄膜的黏附性。但是可以在一定程度上导致薄膜微观结构的变化和sp3/sp2比值的提高,可以在薄膜中掺杂微量的Ar元素,可以有效消除薄膜表面吸附的O,但对薄膜中C-O、C=O和COOH的影响较小。因此,离子轰击法可以作为一种改进类金刚石薄膜质量的方法。 相似文献
12.
13.
采用脉冲直流电源,以甲醇有机溶液作为碳源,在常压60℃的条件下,采用电化学沉积方法在不锈钢表面制备了类金刚石碳薄膜.在电沉积过程中电流密度最高达到150 mA/cm2,沉积速度为500 m/h.用原子力显微镜和扫描电镜表征了薄膜的表面形貌,透射电镜和电子衍射谱表征了薄膜的结构.结果表明:沉积的类金刚石碳DLC膜是由均匀分布的球形纳米颗粒组成,粒度约为300 nm~400 nm,而且致密光滑;不锈钢上沉积的类金刚石薄膜,薄膜的生长是在基体表面划刻的边缘形核中心开始生长,并且生长先由基体的边缘向中心然后逐渐覆盖基体表面. 相似文献
14.
G. S. Sudhir H. Fujii W. S. Wong C. Kisielowski N. Newman C. Dieker Z. Liliental-Weber M. D. Rubin E. R. Weber 《Journal of Electronic Materials》1998,27(4):215-221
Thin films of AlN and GaN were grown by pulsed laser deposition on c-plane sapphire substrates. It is demonstrated that the
structure and surface morphology of layers can actively be controlled by adjusting the nitrogen partial pressure during the
growth. The observed trends in the structural quality of the thin films can be attributed to the changes in the surface diffusion
of adatoms. It is argued that the surface diffusion of adatoms can be influenced by the collisions between the nitrogen gas
molecules and the activated atoms which can reduce the kinetic energy of activated atoms and increase the rate of formation
of immobile surface dimers. Through these nitrogen pressure related effects, thin films with microstructure ranging from crystalline
to amorphous can be produced. The observed similar impact of nitrogen pressure on the growth of GaN and AlN thin films indicates
that a pressure assisted growth procedure is generally applicable to design the surface morphology of group III-nitride thin
films. A minimal surface root mean square roughness of 0.7 nm for amorphous AlN is obtained which compares well with the substrate
roughness of 0.5 nm. Rutherford backscattering spectroscopy of thin films of GaN and AlN showed a large incorporation of oxygen
which was found to reduce the lattice constants of GaN and AlN. 相似文献
15.
16.
17.
S. S. Ang G. Sreenivas W. D. Brown H. A. Naseem R. K. Ulrich 《Journal of Electronic Materials》1993,22(4):347-352
The effects of nitrogen trifluoride (NF3) on the growth and properties of plasma-enhanced chemical-vapor-deposited diamond-like carbon (DLC) films were investigated.
The addition of NF3 increases the deposition rate of DLC film due presumably to the removal of activated hydrogen species by the fluorine radical
(F−). Diamond-like carbon films deposited in a methane/NF3 mixture have a higher refractive index, a lower bulk resistivity, and a lower optical bandgap compared to films deposited
in pure methane due to a lower hydrogen content in the films. Moreover, the bulk resistivity of methane/NF3 DLC films remains constant for annealing temperatures below 400°C. Thus, DLC films deposited with NF3 are more stable than DLC films deposited without NF3. 相似文献
18.
Synthesis of n-Si/diamond-like carbon (DLC) bi-layer films was realized by depositing DLC films on n-Si (100) substrate by a simple electrodeposition technique using acetonitrile (CH3CN) as the electrolyte. The films were characterized by Field Emission Scanning Electron Microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier Transformed Infrared spectroscopy (FTIR) and Raman studies. Solar cell characteristics were investigated critically. Open circuit voltage (Voc) and short circuit current density (Jsc) obtained for the best n-Si (100)/DLC structure were 335 mV and 9.6 mA/cm2, respectively, corresponding to a total conversion efficiency of η= 1.65%. Open circuit photovoltage decay measurement was carried out to determine the carrier lifetime. Photoinduced charge separation in the n-Si (100)/DLC structure could be associated with an increase in the dielectric constant and a decrease in the device resistance. The process is cheap, reproducible and scalable, involving significantly lesser process steps. This is likely to usher in a new hope to the current competitive scenario of photovoltaic (PV) technology. 相似文献
19.
XIONGGang UCERKB WILLIAMSRT TANGPing LINBi-xia FUZhu-xi 《电子显微学报》2005,24(3):178-184
我们分别通过直流反应溅射及脉冲激光淀积法制备了ZnO多晶薄膜。X射线衍射结果显示出薄膜的c轴取向。原子力显微镜证实薄膜的多晶结构。两种方法制备的ZnO在光子激发下都发射较强的带边荧光。绿色荧光未被观察到。激光淀积在(001)硅表面的ZnO的发光源自“自由激子”辐射。激光淀积在(0001)氧化铝晶体表面的ZnO的发光机制则在相当宽的激发强度范围内都呈现出电子.空穴等离子体(electron-hole plasma)的复合特性。 相似文献
20.
反应式脉冲激光溅射淀积AlN薄膜化学稳定性研究 总被引:2,自引:0,他引:2
就反应式脉冲激光溅射淀积制备氮化铝薄膜的过程,讨论了激光脉冲能量密度及脉冲频率对所有制备薄膜结构性能的影响,并对薄膜的化学稳定性作了比较详细的研究,结果表明,当薄膜中存在有未反应的单质铝时,薄膜的化学稳定性较差。比较而言具有高取向性,择优生长的致密AIN微晶膜的化学稳定性优于结构相对疏松的非晶膜。 相似文献