P-type nitrogen-doped ZnO films are prepared successfully by in-situ thermal oxidation of Zn3N2 films. The prepared films are characterized by x-ray diffraction, non-Rutherford back.scattering (non-RBS) spectroscopy...P-type nitrogen-doped ZnO films are prepared successfully by in-situ thermal oxidation of Zn3N2 films. The prepared films are characterized by x-ray diffraction, non-Rutherford back.scattering (non-RBS) spectroscopy, x- ray photoelectron spectroscopy, and photoluminescence spectrum. The results show that the Zn3N1 films start to transform to ZnO at 400℃ and the total nitrogen content decreases with the increasing annealing temperature. The p-type fihns are achieved at 500℃ with a low resistivity of 6.33Ω.cm and a high hole concentration of +8.82 × 10^17 cm-3, as well as a low level of carbon contamination, indicating that the substitutional nitrogen (No) is an effective acceptor in the ZnO:N film. The photoluminescence spectra show clear UV emissions and also indicate the presence of oxygen vacancy (Vo) defects in the ZnO:N films. The p-type doping mechanism is briefly discussed.展开更多
Nitrogen-doped diamond-like carbon (DLC:N) films prepared by the filtered cathodic vacuum arc technology are functionalized with various chemical molecules including dopamine (DA), 3-Aminobenzeneboronic acid (A...Nitrogen-doped diamond-like carbon (DLC:N) films prepared by the filtered cathodic vacuum arc technology are functionalized with various chemical molecules including dopamine (DA), 3-Aminobenzeneboronic acid (APBA), and adenosine triphosphate (ATP), and the impacts of surface functionalities on the surface morphologies, compositions, microstructures, and cell compatibility of the DLC:N films are systematically investigated. We demonstrate that the surface groups of DLC:N have a significant effect on the surface and structural properties of the film. The activity of PC12 cells depends on the particular type of surface functional groups of DLC:N films regardless of surface roughness and wettability. Our research offers a novel way for designing functionalized carbon films as tailorable substrates for biosensors and biomedical engineering applications.展开更多
The nitrogen doping of ZnO film deposited by the magnetron sputtering method is subsequently realized by the hydrothermal synthesis method.The nitrogen-doped ZnO film is preferably(002) oriented.With the increase of...The nitrogen doping of ZnO film deposited by the magnetron sputtering method is subsequently realized by the hydrothermal synthesis method.The nitrogen-doped ZnO film is preferably(002) oriented.With the increase of hexamethylenetetramine(HMT) solution concentration,the average grain size of the film along the 002 direction almost immediately decreases and then monotonously increases,conversely,the lattice strain first increases and then decreases.The structural evolution of the film surface from compact and even to sparse and rough is attributed to the enhanced nitrogen doping content in the hydrothermal process.The transmission and photoluminescence properties of the film are closely related to grain size,lattice strain,and nitrogen-related defect arising from the enhanced nitrogen doping content with HMT concentration increasing.展开更多
Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 (AION) thin films on Si(100) substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown fi...Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 (AION) thin films on Si(100) substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown films have been characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and 3-omega method, respectively. Amorphous and polycrystalline Al2O3 and AlON thin films have been formed at 700 ℃ and 1000 ℃. The thermal conductivity results indicated that the effect of nitrogen doping on the thermal conductivity is determined by the competition of the increase of Al-N bonding and the suppression of crystallinity. A 67% enhancement in thermal conductivity has been achieved for the samples grown at 700 ℃, demonstrating that the nitrogen doping is an effective way to improve the thermal performance of polymer-assisted-deposited Al2O3 thin films at a relatively low growth temperature.展开更多
采用微波等离子体化学气相沉积(MPCVD)方法,通过改变CH_4浓度,在单晶Si(100)基底上制备掺氮纳米金刚石(NCD)薄膜,并以所制备的掺氮NCD薄膜为阴极材料,通过场发射扫描电子显微镜(FESEM)、原子力扫描探针显微镜(AFM)、Raman光谱和S波段射...采用微波等离子体化学气相沉积(MPCVD)方法,通过改变CH_4浓度,在单晶Si(100)基底上制备掺氮纳米金刚石(NCD)薄膜,并以所制备的掺氮NCD薄膜为阴极材料,通过场发射扫描电子显微镜(FESEM)、原子力扫描探针显微镜(AFM)、Raman光谱和S波段射频电子枪等测试方法系统地研究了掺氮NCD薄膜的微观结构对微波场发射性能的影响。结果表明:在CH_4浓度(体积比)为4%下,制备的掺氮NCD薄膜的颗粒呈多面体,而且颗粒尺寸和表面粗糙度较大,薄膜中金刚石相含量较高,这些微观结构使得微波场发射性能较高,在电场强度(E_0)为67.7 V·μm^(-1)时,发射电流密度(J0)高达144.8 m A·cm^(-2)。当升高CH_4浓度,所制备的掺氮NCD薄膜的颗粒尺寸减小而且连成条状结构,表面粗糙度也逐渐降低,薄膜中金刚石相减少、非金刚石相增加,这些微观结构的改变使得微波场发射性能逐渐降低。如当CH_4浓度增加至6%时,在电场强度E_0=67.7 V·μm^(-1)时,场发射电流密度降至37.9 m A·cm^(-2)。结果表明:低CH_4浓度下,掺氮NCD薄膜所具有的微观结构有利于微波场发射。展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10775033 and 11075038
文摘P-type nitrogen-doped ZnO films are prepared successfully by in-situ thermal oxidation of Zn3N2 films. The prepared films are characterized by x-ray diffraction, non-Rutherford back.scattering (non-RBS) spectroscopy, x- ray photoelectron spectroscopy, and photoluminescence spectrum. The results show that the Zn3N1 films start to transform to ZnO at 400℃ and the total nitrogen content decreases with the increasing annealing temperature. The p-type fihns are achieved at 500℃ with a low resistivity of 6.33Ω.cm and a high hole concentration of +8.82 × 10^17 cm-3, as well as a low level of carbon contamination, indicating that the substitutional nitrogen (No) is an effective acceptor in the ZnO:N film. The photoluminescence spectra show clear UV emissions and also indicate the presence of oxygen vacancy (Vo) defects in the ZnO:N films. The p-type doping mechanism is briefly discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.51272237,51272231,and 51010002)the China Postdoctoral Science Foundation(Grant Nos.2012M520063,2013T60587,and Bsh1201016)
文摘Nitrogen-doped diamond-like carbon (DLC:N) films prepared by the filtered cathodic vacuum arc technology are functionalized with various chemical molecules including dopamine (DA), 3-Aminobenzeneboronic acid (APBA), and adenosine triphosphate (ATP), and the impacts of surface functionalities on the surface morphologies, compositions, microstructures, and cell compatibility of the DLC:N films are systematically investigated. We demonstrate that the surface groups of DLC:N have a significant effect on the surface and structural properties of the film. The activity of PC12 cells depends on the particular type of surface functional groups of DLC:N films regardless of surface roughness and wettability. Our research offers a novel way for designing functionalized carbon films as tailorable substrates for biosensors and biomedical engineering applications.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60807001)the Foundation of Henan Educational Committee,China (Grant No. 2010A140017)+1 种基金the the Foundation of Young Key Teachers from University of Henan Province,China (Grant No. 2011GGJS-008)the Graduate Innovation of Zhengzhou University,China (Grant No. 11L10102)
文摘The nitrogen doping of ZnO film deposited by the magnetron sputtering method is subsequently realized by the hydrothermal synthesis method.The nitrogen-doped ZnO film is preferably(002) oriented.With the increase of hexamethylenetetramine(HMT) solution concentration,the average grain size of the film along the 002 direction almost immediately decreases and then monotonously increases,conversely,the lattice strain first increases and then decreases.The structural evolution of the film surface from compact and even to sparse and rough is attributed to the enhanced nitrogen doping content in the hydrothermal process.The transmission and photoluminescence properties of the film are closely related to grain size,lattice strain,and nitrogen-related defect arising from the enhanced nitrogen doping content with HMT concentration increasing.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60976061 and 11028409)
文摘Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 (AION) thin films on Si(100) substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown films have been characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and 3-omega method, respectively. Amorphous and polycrystalline Al2O3 and AlON thin films have been formed at 700 ℃ and 1000 ℃. The thermal conductivity results indicated that the effect of nitrogen doping on the thermal conductivity is determined by the competition of the increase of Al-N bonding and the suppression of crystallinity. A 67% enhancement in thermal conductivity has been achieved for the samples grown at 700 ℃, demonstrating that the nitrogen doping is an effective way to improve the thermal performance of polymer-assisted-deposited Al2O3 thin films at a relatively low growth temperature.
文摘采用微波等离子体化学气相沉积(MPCVD)方法,通过改变CH_4浓度,在单晶Si(100)基底上制备掺氮纳米金刚石(NCD)薄膜,并以所制备的掺氮NCD薄膜为阴极材料,通过场发射扫描电子显微镜(FESEM)、原子力扫描探针显微镜(AFM)、Raman光谱和S波段射频电子枪等测试方法系统地研究了掺氮NCD薄膜的微观结构对微波场发射性能的影响。结果表明:在CH_4浓度(体积比)为4%下,制备的掺氮NCD薄膜的颗粒呈多面体,而且颗粒尺寸和表面粗糙度较大,薄膜中金刚石相含量较高,这些微观结构使得微波场发射性能较高,在电场强度(E_0)为67.7 V·μm^(-1)时,发射电流密度(J0)高达144.8 m A·cm^(-2)。当升高CH_4浓度,所制备的掺氮NCD薄膜的颗粒尺寸减小而且连成条状结构,表面粗糙度也逐渐降低,薄膜中金刚石相减少、非金刚石相增加,这些微观结构的改变使得微波场发射性能逐渐降低。如当CH_4浓度增加至6%时,在电场强度E_0=67.7 V·μm^(-1)时,场发射电流密度降至37.9 m A·cm^(-2)。结果表明:低CH_4浓度下,掺氮NCD薄膜所具有的微观结构有利于微波场发射。