衬底温度对AlN薄膜结构及电阻率的影响

采用直流反应磁控溅射法在Si(111)基片上制备了AlN薄膜,利用XRD、原子力显微镜(AFM)、电流-电压(I-V)测试仪等对不同衬底下制备薄膜的结构、形貌及电阻率等进行了分析表征。结果表明:随着衬底温度的升高,晶粒逐渐长大,AlN(002)择优取向明显改善,600℃达到最佳。一定范围内提高温度使晶粒均匀、致密,有利于改善表面粗糙情况和提高电阻率,550℃时表面粗糙度达到最低(2.8 nm)且有最大的电阻率(3.35×1012Ω.cm);同时薄膜应力随温度升高有增大趋势。     

衬底温度对CZTSSe薄膜结构特性的影响

采用热蒸发法制备铟锌锡硫(CZTSSe)薄膜。采用低 温一步 法在300℃衬底温度下制备CZTSSe薄膜;采用两步法,即在衬底温度 分别为300℃制备CZTSSe 薄膜;将衬底温度设定为480℃不变,一步蒸发沉积CZTSSe薄膜。通 过对X射线衍射(XRD)、 扫描电镜(SEM)、拉曼谱对比发现,在300℃低温下一步法和300℃ 、480℃两 步法沉积的薄膜表面粗糙,碎小晶粒较多;在480℃一步高温法制备 的薄膜表面平整, 晶粒大小均匀,3个衍射峰的半高峰宽变窄,薄膜的结晶质量得到 改善,且没有发现其它杂相的拉曼特征峰,沉积出适合作为制备CZTSSe薄膜太阳电池的 吸收层。     

衬底温度对AIN薄膜结构及电阻率的影响

采用直流反应磁控溅射法在Si(111)基片上制备了AIN薄膜,利用XRD、原子力显微镜(AFM)、电流-电压(I-V)测试仪等对不同衬底下制备薄膜的结构、形貌及电阻率等进行了分析表征.结果表明:随着衬底温度的升高,晶粒逐渐长大,AIN(002)择优取向明显改善,600℃达到最佳.一定范围内提高温度使晶粒均匀、致密,有利于改善表面粗糙情况和提高电阻率,550℃时表面粗糙度达到最低(2.8 nm)且有最大的电阻率(3.35×1012Ω·cm);同时薄膜应力随温度升高有增大趋势.     

衬底温度对ZnO纳米结构的影响

利用超声喷雾热解(USP)技术,以普通玻璃为衬底,制备了不同衬底温度下的系列ZnO薄膜.用扫描电镜(SEM)和X射线衍射(XRD)研究了衬底温度对ZnO结构的影响.结果表明,薄膜的微观结构随衬底温度变化显著.在410℃获得了ZnO纳米棒,纳米棒直径在50 nm左右,沿c轴择优生长,结晶质量较好.     

富碲碲化铅薄膜的晶体结构、表面形貌、元素深度分布和中红外光学常数

对由富碲( <1mol.% )碲化铅晶体材料热蒸发制备的薄膜进行了表征.结果表明:薄膜是多晶的,具有NaCl型晶体结构,表面晶粒分布均匀,在膜层的深度方向约 170nm内富碲的组分均匀分布.对比薄膜表面抛光前后的中红外光学常数表明表面散射对薄膜光学性质的影响极小.     

衬底温度对氧化锌薄膜场发射性能的影响

利用射频磁控溅射法制备了不同衬底温度的氧化锌(ZnO)薄膜.研究了其场发射特性,分析了场发射特性和衬底温度的变化关系.实验结果表明, 开启电场随着衬底温度的增加呈先增大后减小的趋势,场发射特性的变化是由于衬底温度的改变引起表面形貌的变化所致.衬底温度为300 ℃时沉积的ZnO薄膜样品粗糙度最小,场发射性能最差,其开启场强为1.7 V/μm,场强为3.8 V/μm时电流密度仅为0.001 97 A/cm2;衬底温度为400 ℃时沉积的ZnO薄膜样品表面粗糙度最大,场发射特性也优于其他薄膜;开启场强为0.82 V/μm, 场强为3.8 V/μm时电流密度稳定在0.03 A/cm2.Fowler-Nordheim(F-N)曲线为直线表明, 电子是在外加电场的作用下隧穿表面势垒束缚发射到真空的.     

衬底和退火温度对多晶硅薄膜结构及光学性质影响

通过射频等离子体增强化学气相沉积(RF-PECVD)技术与退火处理制备多晶硅薄膜,研究了衬底和退火温度对所制薄膜的结构及光学性质的影响。本次试验最大的晶粒尺寸是在衬底温度为250℃获得,考虑薄膜表面的质量,最佳的退火温度为635℃,衬底温度为225℃,在玻璃衬底形成的晶粒大于50 nm,光学带隙为1.5 e V。结果表明:衬底温度影响着薄膜中氢含量以及相关的缺陷。随着退火温度的升高,晶化率的提高,光学带隙先减小后增大。     

衬底表面状态对碲镉汞薄膜表面起伏的影响

通过改变碲锌镉衬底的表面加工方法及溴-甲醇腐蚀液的浓度,研究衬底的表面状态对碲镉汞薄膜表面起伏情况的影响。利用傅里叶红外透射(FTIR)光谱议、晶片扫描成像系统、光学显微镜等工具对不同条件下的碲镉汞薄膜的表面起伏情况进行观察和比较。研究初步发现碲锌镉衬底不经过化学抛光,以及不经过腐蚀直接进行外延的情况下得到的碲镉汞薄膜的表面起伏状况会得到一定程度的改善,但是考虑溴-甲醇腐蚀液对机械抛光造成的表面应力的释放作用以及外延过程中的衬底回熔的相互作用会使得外延所得碲镉汞薄膜表面起伏情况更加复杂。因此,仍需要对衬底使用前的化学抛光对薄膜表面起伏的作用以及确定合适的溴-甲醇腐蚀液的浓度进行进一步的研究。     

基片表面状态对Pb1-x GexTe薄膜红外光学性能的影响

在高真空中用热蒸发的方法沉积了碲锗铅Pb1-xGexTe薄膜。分析了基片表面状态(粗糙度、晶向、温度)对膜层结构和红外光学特性的影响,发现光滑表面容易得到致密膜层和高红外折射率;随着沉积温度的增加,膜层的短波吸收边(λc)往长波方向移动。     

沉积温度对PbTe薄膜结构和光学性能的影响

采用电阻热蒸镀法,分别以不同的沉积温度在锗基底上制备了PbTe薄膜。用X射线衍射仪(XRD)、原子力显微镜(AFM)和红外光谱测试仪(System2000)表征了不同沉积温度下薄膜的微结构和光学特性.结果表明,沉积温度对PbTe薄膜的结构、择优取向、生长方向、晶粒大小、禁带宽度以及短波吸收限均有明显影响.     

Electrical properties of tellurium thin films

Semiconducting properties of evaporated tellurium thin films, in the thickness range of 100 to 400 Å, are studied and correlated with observed structural properties. It is found that less-than-monolayer gold films can act as nucleation sites and stimulate the growth of large crystallites in deposited Te films. The Au-nucleated Te films are preferentially oriented with the c axis in the substrate plane and have crystallite diameters ranging from 2 to 5 µm. Hall mobilities as high as 250 cm²/V ċ s are observed in 400-Å Au-nucleated films with 5-µm crystallites. These large-grain films exhibit a temperature dependence for mobility of the form µ ∼ T^3/2between 85°K and 250°K, while the carrier concentrations in the films do not change appreciably with temperature. Transconductances greater than 1000 µmhos are achieved for Au-nucleated Te thin-film transistors with 3-mil channels (operating with a saturated drain current of 1 mA). Several devices exhibit field-effect mobilities greater than 100 cm²/V ċ s, a value consistent with the observed Hall mobilities for similar films. Transconductance measurements indicate that Te thin-film transistor (TFT) instabilities result primarily from hole trapping at the Te-insulator interface. It is possible to alter the threshold voltage of Te TFTs by applying a gate bias at room temperature. Improved stability (changes in V0less than 50 mV in 1 h) is observed at 77°K. From the observed changes in threshold, a lower limit of the trapping-state density at the surface is inferred to be 5×10¹²traps/cm². The surface-state density at the Te-SiO interface is estimated to be less than 6×10¹²surface states/cm²ċ eV as determined from capacitance and conductance measurements.     

基片温度对TiB2薄膜生长形貌及力学性能的影响

TiB2是一种超硬材料,块体TiB2的硬度高达HV30Gpa,而且耐腐蚀、抗氧化,还具有优良的导电性能,是一种受到广泛重视的导电耐磨涂层材料[1].     

沉积预制层衬底温度对CIGS薄膜结构特性的影响

采用三步共蒸发工艺在玻璃衬底上制备CIGS薄膜, 研究沉积预制层的衬底温度对CIGS薄膜 结构特性的影响。薄膜的厚度、组份、晶相结构、表观形貌和电学特性分别由台阶仪、X射 线荧光光谱(XRF)、X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)和霍耳效应测量仪来表征。沉积 预制层的衬底温度 较低(如300℃)时,预制层中Ga含 量较低,容易形成In₂Se₃相;而衬底温度较高(如400℃) 时,预制层中Ga含量较高,容易形成(In,Ga)₂Se₃相;原因是Ga₂Se₃的形成焓(－462.4kJ/mol)比In₂Se₃的(－360kJ/mol)低,没有In₂Se₃稳定;In₂Se₃相比Ga₂S e₃相更容易稳定存在,尤其是在低温下;当温度较高 时,Ga₂Se₃相也容易存在,与In₂Se₃一起形成(In,Ga)₂Se₃固溶体。而且,衬 底温度较高(如400℃)时,沉积 的CIGS薄膜中的Ga含量比其它两种衬底温度下沉积的薄膜都高,薄膜粗糙度较小,迁移率和 载流子浓度都比较大,电阻率较小。     

Influence of substrate temperature on the properties of fluorinated silicon-nitride thin films deposited by IC-RPECVD

Fluorinated silicon-nitride films have been prepared from an Ar/SiF₄/NH₃ gas mixture by inductively coupled remote plasma-enhanced chemical vapor deposition (IC-RPECVD) at different substrate temperatures, ranging from 150 to 300°C. All of the resulting deposited silicon-nitride films were free of Si-H bonds, showed high dielectric breakdown fields (≥8 MV cm^?1), and had root mean square (rms) surface roughness values below 3 Å. The films’ refractive indices and the contents of O and F remain constant, but Si/N ratios drop from 5 to 2 and N-H bond concentrations decrease in the range (1.3–0.9) × 10²² cm^?3 as the substrate temperature increases. The density of interface states (D_it) with c-Si was reduced from 2.4 × 10¹² to 8 × 10¹¹ eV^?1 cm^?2 at substrate temperatures ≥250°C.     

Influence of substrate temperature on structural and optical properties of RF sputtered ZnMnO thin films

The ZnMnO thin films were deposited on glass substrates by radio frequency magnetron sputtering method. The properties of ZnMnO thin films were investigated by high-resolution x-ray diffractometer (HRXRD),atomic force microscopy (AFM), UV-Vis spectrometer and room temperature photoluminescence (PL), under the influence of substrate temperature. The substrate temperature was varied from 300, 400 and 500°C. With increasing the substrate temperature, the structure of the films changed from cubic to hexagonal. The cubic ZnMnO thin films grown along [210] direction, while the hexagonal ones grown along [002] direction. The changes in surface morphology provided a proof on the structural transition. Also, decrease and increase of optical band gap is associated with cubic or hexagonal structure of the films.

     

衬底温度对纳米晶SnO_2薄膜结晶特性的影响

阐述了金属氧化物SnO2纳米薄膜研究的发展情况及其应用前景,介绍了采用磁控溅射技术,使用混合气体Ar和O2,在衬底温度为150～400℃的耐热玻璃基片上制备了纳米晶SnO2∶Sb透明导电薄膜。通过测定x射线衍射谱,表明薄膜择优取向为[110]和[211]方向,SnO2∶Sb薄膜的结晶特性随衬底温度变化。     

Influence of cadmium concentration on the optical and structural properties of cadmium selenide thin films

Thin films of cadmium selenide (CdSe) and Cd_xSe_100−x (x=54, 34) have been deposited by vacuum evaporation onto ultraclean glass substrates at room temperature from as-prepared powders. Fabricated samples were characterized using X-ray diffraction (XRD), UV–vis and Fourier transform infrared (FTIR) spectroscopy. XRD indicated the formation of polycrystalline Cd_xSe_100−x thin films polycrystalline in nature with the preferred orientation along the (002) plane. The crystallite sizes of thin films calculated by the Scherer formula were found to be in the range of 29–82 nm. The crystallinity of thin films degraded on increasing the Cd concentration in the Cd–Se system. The band gaps of thin films were obtained from their optical absorption spectra, which were found in the range of 1.69–2.20 eV. The band gap of the Cd₃₄Se₆₆ thin films was found to be very high because of the decrease of their crystallites sizes in comparison to the CdSe and Cd₅₄Se₄₆ thin films. From the FTIR spectra it was revealed that the Cd–Se peaks shifted to lower wavelengths with increase in selenium concentration. The SEM measurements for CdSe, Cd₅₄Se₄₆ and Cd₃₄Se₆₆ thin films reveal that the particle size and the crystalline nature decreased when Se content increased in the system.     

衬底温度对电子束沉积LaF3薄膜性能的影响

采用电子束沉积的方法分别在K9玻璃、紫外熔凝石英和Si基片上制备了LaF3单层膜,研究了衬底温度对LaF3薄膜结构和光学性能的影响.衬底温度从200℃上升到350℃,间隔为50℃,用分光光度计测量样品的透射率光谱曲线,并进行光学常数的计算.利用原子力显微镜(AFM)进行表面粗糙度的标定,利用ZYGO干涉仪测量基板镀膜前...     

Influence of substrate temperature and post deposition annealing on the properties of vacuum deposited ZnSe thin films

The effects of substrate temperature and post deposition annealing on the structural, optical and electrical properties of vacuum deposited ZnSe thin films are presented here. The chemical composition of the films varied drastically with substrate temperature which in turn caused changes in various properties of the films. The grain size of the films increased with substrate temperature and also after annealing. The electrical properties of the films were found to be varying as a function of chemical composition and grain size.