不同衬底温度对ZnO薄膜结构和光学性质的影响

利用磁控溅射在玻璃基片上制备了不同衬底温度下的ZnO薄膜.借助X射线衍射仪(XRD)、吸收光谱、光致发光谱(PL)等手段研究了衬底温度对ZnO薄膜的微结构、光致发光性能的影响.结果表明:所有样品均呈现ZnO六角纤锌矿结构且具有高度c轴择优取向;ZnO薄膜在可见区的吸收系数很小,在紫外区有很高的吸收系数;室温下的荧光光谱显示薄膜具有较强的紫光发射.     

等离子束辅助沉积制备ZnO薄膜的特性研究

采用等离子束辅助沉积的方法在n-Si(001)衬底上制备出ZnO薄膜。X射线衍射谱显示，所制备的ZnO薄膜有较强的(002)晶面衍射峰，表明ZnO薄膜为c轴择优取向生长的，并且随着退火温度升高，晶粒逐渐增大，衍射峰逐渐增强。光致发光谱测量发现，样品分别在3．28eV和2．48eV存在紫外发射和深能级发射两个较强的发射峰，并且随着退火温度升高，深能级发射逐渐减弱，紫外发射峰得到进一步改善。四探针测试电阻率结果表明，随着退火温度的升高，ZnO薄膜的电阻率呈线性增加。     

Al掺杂对ZnO薄膜结构和光学性能的影响

研究了Al掺杂对采用直流磁控溅射方法制备的ZnO薄膜结构及光学性能的影响。X射线衍射结果揭示薄膜具有良好的C轴择优取向生长特性,同时,衬底温度对它们的透射谱和荧光谱有着明显影响,所有薄膜都有大于86%的可见光透过率和陡峭的本征吸收边,但ZAO薄膜的光学透过率略低。Al掺杂导致了更宽的光学带隙,光致发光光谱显示ZnO具有较强的近带本征吸收峰和深能级发射峰,但Al掺杂使得深能级发射峰降低。随着衬底温度的升高,近带边吸收峰蓝移,与光学带隙Eg变化趋势一致。     

Fe掺杂对ZnO薄膜的微结构与光学性质的影响

采用溶胶一凝胶法在石英玻璃衬底上制备了Fe掺杂的ZnO薄膜,研究了不同的Fe掺杂浓度对ZnO薄膜的微结构与光学性质的影响.利用x射线衍射分析了薄膜样品的晶向和晶相.利用原子力显微镜观测了薄膜样品的表面形貌,利用双光束紫外-可见分光光度计分析了znO薄膜样品的光学性质.实验结果表明:所有ZnO薄膜样品都是六角纤锌矿结构,ZnO晶粒沿c轴择优生长.质量分数为1%fe掺入之后,ZnO薄膜的C轴择优取向进一步增强,薄膜的晶化质量也得到进一步提高.当Fe的掺杂浓度高于1%时,ZnO薄膜(002)衍射峰的强度又降低了,这可能是由于Fe2+(x=2或3)和zn2+具有不同的离子半径,大量的Fe2+进入晶格取代Zn2+导致晶格严重畸变,从而影响了znO晶粒的正常生长.所制备的ZnO薄膜在可见光区都具有高的透射丰,由吸收边估算出来的ZnO薄膜的光学带隙表明:随着Fe的掺杂浓度的提高,光学带隙逐渐展宽.     

Mn掺杂ZnO纳米晶粉体的结构及磁性研究

为探寻ZnO稀磁半导体材料的室温铁磁性来源,采用溶胶凝胶法制备掺Mn量为0、1%、2%和3%的ZnO粉体,利用X射线衍射仪、扫描电子显微镜、X射线光电子能谱仪以及振动样品磁强计,研究粉体的形貌特征、物相、电子结构以及室温磁性能。结果表明:掺Mn可使粉体粒度减小;Mn以离子形式取代Zn的位置,保持了本征ZnO的六方纤锌矿结构,无第二相形成;掺Mn形成的Zn—Mn键和Mn—O—Mn键改变了本征ZnO的缺陷结构,从而导致磁性变化;样品中的氧空位浓度决定ZnO的室温铁磁性;掺Mn量为1%时为最优掺入量,具有最大的饱和磁矩22.599×10?2 emu/g。     

(110)和(002)择优取向ZnO薄膜的制备及光学性能研究

运用射频溅射法在Si和LaNiO3/Si衬底上分别制备了高度(002)和(110)取向的ZnO薄膜.通过X射线衍射(XRD)和扫描电子显微镜(SEM)表征,发现ZnO/LaNiO3/Si薄膜的(110)取向度高达96%,ZnO/Si薄膜为(002)择优取向,两种薄膜表面均致密平整,晶粒尺寸小于80nm.光致发光结果表明,ZnO/LaNiO3/Si薄膜的光致发光峰主要为带边发射的紫外光,而ZnO/Si薄膜的光致发光峰主要为过量氧导致的缺陷引起的缺陷发光峰.因此,采用LaNiO3薄膜作为ZnO在Si衬底上生长的过渡层,能够有效抑制缺陷发光,改善ZnO薄膜的发光性能.     

Investigations of ZnO thin films deposited by a reactive pulsed laser ablation

Highly transparent ZnO thin films were deposited at different substrate temperatures by pulsed laser deposition in an oxygen atmosphere. The thin films were characterized by various techniques including X-ray diffraction, scanning electron microscopy, optical absorption, and photoluminescence. We demonstrated that oriented wurtzite ZnO thin films could be deposited at room temperature using a high purity zinc target. Variable temperature photoluminescence revealed new characteristics in the band edge emission. The underlying mechanism for the observed phenomena was also discussed.     

Preparation and characterization of transparent conductive zinc doped tin oxide thin films prepared by radio-frequency magnetron sputtering

High transparent and conductive thin films of zinc doped tin oxide (ZTO) were deposited on quartz substrates by the radio-frequency (RF) magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO2 ceramic target.The effect of substrate temperature on the structural,electrical and optical performances of ZTO films has been studied.X-ray diffraction (XRD) results show that ZTO films possess tetragonal rutile structure with the preferred orientation of (101).The surface morphology and roughness of the films was investigated by the atomic force microscope (AFM).The electrical characteristic (including carrier concentration,Hall mobility and resistivity) and optical transmittance were studied by the Hall tester and UV- VIS,respectively.The highest carrier concentration of -1.144×1020 cm-3 and the Hall mobility of 7.018 cm2(V ·sec)-1 for the film with an average transmittance of about 80.0% in the visible region and the lowest resistivity of 1.116×10-2 Ω·cm were obtained when the ZTO films deposited at 250 oC.     

Er／Yb／Al掺杂ZnO薄膜的结构与形貌研究

采用射频磁控溅射技术在室温下Si衬底上制备了ZnO薄膜和Er／Yb／Al掺杂的ZnO薄膜。通过对XRD的结构分析表明：未掺杂ZnO薄膜沿c取向性生长,掺杂ZnO薄膜偏离了正常生长,变为（102）取向性生长的纳米多晶结构;Er／Yb／Al掺杂的ZnO薄膜的晶粒尺寸随着Er元素含量的增多而减小。经AFM对其形貌分析表明：Er^3＋、Yb^3＋、Al^3＋的掺入引起了ZnO薄膜晶格场变化,使薄膜表面粗糙度变大。     

衬底温度对ZnO薄膜结构和光学特性的影响

采用射频磁控溅射的方法在不同温度下Si(111)衬底上制备出了具有高c轴择优取向的ZnO薄膜,利用X射线衍射(XRD),原子力显微镜(AFM),光致发光(PL)谱等分析手段研究了衬底温度对ZnO薄膜微观结构及发光特性的影响.通过XRD和AFM分析发现随着衬底温度的升高,制备样品的X射线衍射半高宽(FWHM)减小,晶粒尺寸增大,在300 ℃时晶粒尺寸达到最大,但随温度的进一步升高(至400 ℃)晶粒尺寸减小,缺陷增多.薄膜样品PL谱均在520nm处出现绿光发射峰,本文认为这是由于氧空位(V_O)和氧替位(O_(Zn))共同作用的结果,绿光发射峰强度与其结晶质量密切相关,结晶质量越好,杂质和缺陷态就越少,发光峰越弱.     

Sputtering of ZnO buffer layer on Si for GaN blue light emitting materials

The preparation of high quality ZnO/Si substrates for the growth of GaN blue light emitting materials is considered. ZnO thin films have been deposited on Si (100) and Si (111) substrates by conventional magnetron sputtering. Morphology, crystallinity and c-axis preferred orientation of ZnO thin films have been investigated by transmitting electron microscopy (TEM), X-ray diffraction (XRD) and X-ray rocking curve (XRC). It is proved that the ZnO thin films have perfect structure. The full-width-at-half-maximum (FWHM) of the ZnO(002) XRC of these films is about 1°, while the minimum is 0.353°. This result is better than the minimum FWHM (about 2°) reported by other research groups. Moreover, comparison and discussion are given on film structure of ZnO/Si(100) and ZnO/Si(111).     

Er^＋注入Yb掺杂的ZnO波导膜的光学及结构特性研究

利用射频磁控溅射技术在蓝宝石衬底上沉积ZnO：Yb光波导薄膜,然后用离子注入技术将能量为200keV的Er^＋离子注入薄膜中,剂量为1×10^15ions／cm2。应用棱镜耦合技术、卢瑟福背散射（RBS）技术、X射线衍射（XRD）技术和荧光光谱等技术研究了薄膜的波导性质、基本结构、厚度、组分、Er^＋的射程情况及光学频率上转换性质。实验发现掺杂Yb和Er的薄膜可以形成光波导结构,但波导质量较纯ZnO波导膜差,膜的有效折射率及沉积速率随Yb掺杂量增加有减小趋势;薄膜呈ZnO高度c-轴取向生长,Yb和Er能有效掺杂进ZnO晶格,ZnO晶格常数受Yb掺杂量的不同而变化;在980nm激光激发下没有发现在300-720nm间的光学频率上转换。     

Structural,optical and electrical properties of Li-doped ZnO thin films influenced by annealing temperature

Li-doped Zn O thin films had been grown by radio frequency magnetron sputtering and then annealed under various annealing temperatures. The characteristics of Zn O films were examined by XRD, FESEM, Hall measurement and optical transmission spectra. Results showed that p type conduction was observed in Lidoped Zn O films annealed at 500-600 ℃ and the p type Zn O films possessed a good crystalline with c-axis orientation, dense surface, and average transmission of about 85% in visible spectral region.     

Fabrication of GaN films through reactive reconstruction of magnetron sputtered ZnO/Ga_2O_3

1　INTRODUCTIONGallium nitride (GaN) is one of the most po tential semiconductors. GaN has a direct energyband gap of 3.4 eV at room temperature and highexternal photoluminescence quantum efficiency, aswell as a high excitonic binding energy of20 meV[1]. It is an ideal material for fabrication ofultraviolet(UV)/blue/green light emitting diodes(LEDs), laser diodes(LDs), UV detectors and de vices operating in high temperature, high frequen cy and high power co…     

梯度掺杂AZO薄膜的制备及其性能表征

采用Sol-Gel法,以不同铝离子浓度的溶胶梯度掺杂的方法制备了Al掺杂ZnO（AZO）薄膜,用XRD衍射仪和SEM扫描电镜对该薄膜进行了结构和形貌分析,并对其电学性能和光学性能进行了研究。结果表明,梯度掺杂的AZO薄膜比单一浓度掺杂5.0 at%（原子数百分比）的薄膜具有更明显的c轴择优取向,更强的本征紫外发光峰和近紫外发光峰。当薄膜的退火温度在500~650℃区间时,薄膜电阻率稳定在10-2Ω.cm,高于700℃时,薄膜电阻率明显升高。     

脉冲激光沉积法制备Zn1-xCdxO薄膜及结构和光学性能研究

采用脉冲沉积（PLD）法在石英玻璃衬底上制备了Zn1-xCdxO薄膜,X射线衍射仪（XRD）结果表明,所制备的Zn1-xCdxO薄膜具有与ZnO同样的六角纤锌矿结构,且薄膜具有沿着（002）晶面择优取向生长特征,随着Cd掺杂浓度（x）的增加,衍射峰（002）向小角度方向移动,晶格常数增加。光致发光光谱表明Zn1-xCdxO薄膜随着Cd的掺杂浓度的增加使光学带隙逐渐变窄了,且控制掺入量就可以实现ZnO薄膜禁带宽度在一定范围内连续可调。     

Fabrication of GaN films through reactive reconstruction of magnetron sputtered ZnO／Ga2O3

A simple and easily operated technique was developed to fabricate GaN films. GaN films possessing hexagonal wurtzite structure were fabricated on Si(111) substrates with ZnO buffer layers through nitriding Ga2O3 films in the tube quartz furnace. ZnO buffer layers and Ga3O3 films were deposited on Si substrates in turn by using radio frequncy magnetron sputtering system before the nitriding process. The structure and composition of GaN films were studied by X-ray diffraction, selected area electron diffraction and Fourier transform infrared spectrophotometer. The morphologies of GaN films were studied by scanning electron microscopy. The results show that ZnO buffer layer improves the crystalline quality and the surface morphology of the films relative to the films grown directly on silicon substrates. The measurement result of room-temperature photoluminescence spectrum indicates that the photoluminescence peaks locate at 365 nm and 422 nm.     

基片表面朝向对ZnO纳米线生长机理的影响

采用热蒸发ZnO粉末法,以金膜为催化剂,在两片表面分别朝上和朝下的Si(100)基片上生长ZnO纳米线(样品分别标为1#和2#)。X射线衍射(XRD)图谱上只存在ZnO的(002)衍射峰,说明ZnO纳米线沿(001)择优取向。通过扫描电子显微镜(SEM)表征发现,ZnO纳米线整齐排列在Si基片上,直径在100nm左右,平均长度为4mm。通过分析得出,两种基片上生长的ZnO纳米线的生长机理是不相同的:1#样品,在基片表面上先生长ZnO薄膜,再在薄膜上生长ZnO纳米线;2#样品,ZnO纳米线直接外延生长在基片表面。结果显示基片表面的朝向影响ZnO纳米线的生长机理。     

ZnO纳米阵列的水溶液法制备及其荧光特性

采用简单的低温水溶液法,在修饰有ZnO种子膜的玻片上制备出形貌规整、取向性较好的ZnO纳米棒阵列。利用场发射扫描电子显微镜(FE-SEM)、X射线衍射仪(XRD)和荧光测试仪(PL)等对产物的形貌、结构、光致发光特性进行了表征。结果表明,水热生长12 h后,能够得到均匀致密、高度取向的氧化锌纳米棒阵列,每个纳米棒直径大约为150 nm,长度为1.5μm左右。XRD结果显示,ZnO纳米棒的结构为纤锌矿结构,并沿c轴择优生长。荧光测试结果显示,所制备的ZnO纳米棒阵列在383 nm附近有一个强的紫外发射峰,同时在可见光区出现比较弱的蓝绿光发射峰。     

ZnO films on transferable and low thermal resistance graphite substrate grown by ultrasonic spray pyrolysis

ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method with Zn(CH 3 COO) 2 ·2H 2 O aqueous solution as precursor. The crystalline structure, morphology, and optical properties of the as-grown ZnO films were investigated systematically as a function of deposition temperature and growth time. Near-band edge ultraviolet(UV) emission was observed in room temperature photoluminescence spectra for the optimized samples, yet the usually observed defect related deep level emissions were nearly undetectable, indicating that high optical quality ZnO thin fi lms could be achieved via this ultrasonic spray pyrolysis method. Considering the features of transferable and low thermal resistance of the graphite substrates, the achievement will be of special interest for the development of high-power semiconductor devices with suffi cient power durability.