Co₃O₄-loaded ZnO nanofibers for excellent hydrogen sensing

Lee, Jae-Hyoung,Kim, Jin-Young,Kim, Jae-Hun,Mirzaei, Ali,Kim, Hyoun Woo,Kim, Sang Sub Elsevier 2019 International journal of hydrogen energy Vol.44 No.50

<P><B>Abstract</B></P> <P>The development of outstanding H<SUB>2</SUB>-sensing materials is vital for the realization of ecofriendly devices using H<SUB>2</SUB>-based energy. ZnO nanofibers have excellent H<SUB>2</SUB>-sensing performance. In this study, we synthesized a series of Co<SUB>3</SUB>O<SUB>4</SUB>-loaded ZnO nanofibers with the formula (1-x)ZnO-xCo<SUB>3</SUB>O<SUB>4</SUB> (x = 0.03, 0.05, 0.1, and 0.15, representing the molar ratio of Co<SUB>3</SUB>O<SUB>4</SUB>) via electrospinning to improve the H<SUB>2</SUB>-sensing properties of pristine nanofibers. The sensing results indicated that a sensor with a nominal composition of 0.95ZnO-0.05Co<SUB>3</SUB>O<SUB>4</SUB> had the highest response of ~133 to 10 ppm H<SUB>2</SUB> gas, with good H<SUB>2</SUB> selectivity. The main mechanisms underlying the excellent H<SUB>2</SUB>-sensing capability of the optimized gas sensor involved ZnO surface/grain boundaries and Co<SUB>3</SUB>O<SUB>4</SUB>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The <I>n</I>-<I>p</I> ZnO–Co<SUB>3</SUB>O<SUB>4</SUB> composite nanofibers showed higher H<SUB>2</SUB> sensing response, superior to that of pristine <I>n</I>–ZnO nanofibers. </LI> <LI> The composite nanofibers with composition of 0.95 ZnO-0.05 Co<SUB>3</SUB>O<SUB>4</SUB> showed the highest response to H<SUB>2</SUB> at 300 °C. </LI> <LI> H<SUB>2</SUB> sensing was related to the H<SUB>2</SUB>-induced reduction of resistance in ZnO and formation p-Co<SUB>3</SUB>O<SUB>4</SUB>/n-ZnO heterojunctions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Change of potential barriers at ZnO/ZnO homointerfaces in the H<SUB>2</SUB> atmospheres, energy levels of ZnO and Co<SUB>3</SUB>O<SUB>4</SUB> after intimate contact, and responses of Co<SUB>3</SUB>O<SUB>4</SUB> loaded ZnO to H<SUB>2</SUB>, CO, NO<SUB>2</SUB> gases.</P> <P>[DISPLAY OMISSION]</P>

ZnO 박막내 산소관련결함과 녹색 발광의 상관관계

배명욱,장승훈,한문섭 한국물리학회 2014 새물리 Vol.64 No.3

Zinc-oxide (ZnO) films were deposited by using an RF magnetron sputtering method. By controlling the ratio of Ar to O₂ gases, we synthesized two types of films. Then, we performed furnace annealing at 900℃ under ambient O₂ or N₂ gases. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) techniques were applied to characterize the structural and the optical properties of the ZnO films. When a ZnO film with low oxygen content is initially deposited, the crystal structure is well formed in the transversal, as well as the longitudinal, direction. Also, a sufficient supply of oxygen molecules by O₂ annealing promoted the formations of antisite oxygen and oxygen interstitial defects. From the analyses of the PL and the XPS data for all samples, we ascribe the main origin of green emis-sion from the ZnO film to oxygen-related defects. The type of oxygen-related defect caused by O₂ post-annealing was determined by the initial conditions of the fabrication and affected luminescent property in the ZnO film. The results of this work should be important for the development of green-light-emitting diodes with ZnO thin films. RF magnetron 스퍼터링방법을 이용하여 ZnO 박막을 제작하였다. Ar 및 O₂ 스퍼터링 가스의 비율을 조절하여 두 종류의 ZnO 박막을 만들었고, 산소 및 질소 분위기에서 900℃ 조건으로 각각 열처리를 실시하였다. 구조 및 광학적 특성을 분석하기 위해서 X-ray Diffraction, X-ray Photoelectron Spectroscopy (XPS), Photoluminescence (PL) 측정을 하였다. 산소주입량이 적은 시료의 경우, 증착 직후 종단면 결정뿐만 아니라 횡단면 결정까지도 비교적 잘 성장되었으며, 산소 분위기에서의 후열처리후에도 시료 내 결정구조가 잘 유지됨과 동시에 ZnO 박막 안으로 산소 공급이 원활하게 이루어짐으로써 Antisite 산소 및 Oxygen Interstitial 결함 생성이 활발하게 일어남을 확인하였다. XPS 및 PL 측정결과를 분석하여 열처리 과정 중 생성된 산소 관련 결함들이 ZnO 박막 내 녹색발광의 주요한 원인이라고 판단하였다. 증착방법 및 조건에 따라 증착 완료 후 산소분위기 후열처리에 의한 산소관련 결함의 종류 및 형성 규모가 결정되며 이는 박막의 발광 강도에 직접적인 영향을 주었다. 이러한 결과는 ZnO 박막을 이용한 녹색발광소자 제작시 중요하게 고려되어야 할 요소라고 판단된다.

MgZnO/ZnO 이중 구조의 성장을 위한 사파이어 기판에서의 InZnO 버퍼층 연구

염아람,김홍승,안형수,장낙원 한국물리학회 2019 새물리 Vol.69 No.1

The replacement of Zn by Mg increases the bandgap of ZnO from 3.37 eV to 7.8 eV. The quantum-well structure of MgZnO/ZnO can be utilized as an active layer for ultra violet light-emitting diode (UV-LED) and high-mobility field effect transistor (HEMT). However, forming a high-quality MgZnO/ZnO heterostructure is difficult because of the lattice mismatch and surface roughness of the ZnO layer on a sapphire substrate. This study was carried out to introduce an InZnO buffer layer for the formation of a good-quality ZnMgO/ZnO quantum-well structure. Pulsed laser deposition (PLD) was used for this purpose, and X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to evaluate the structural properties. Atomic force microscopy (AFM) was also performed to observe surface changes. The addition of only a small amount of In improved the surface roughness of the buffer layers. This revealed that a buffer layer of InZnO is favorable for growing ZnMgO/ZnO thin films of high quality. Mg에 의한 Zn의 치환은 ZnO의 밴드 갭을 3.37 eV에서 7.8 eV로 증가시킨다. 이를 이용하여 ZnMgO/ZnO의 양자우물 구조 형성 시 UV-LED (ultra violet light-emitting diode) 및 ZnO 기반 고이동도 전계효과 트랜지스터의 활성층으로 활용할 수 있다. 하지만 양질의 ZnMgO/ZnO 구조를 사파이어 기판위에 형성 시 격자 불일치 및 ZnO 층의 표면 거칠기 등으로 양질의 이중 구조 박막의 형성이 어려운 실정이다. 본 연구는 양질의 ZnMgO/ZnO 양자우물 구조 형성을 위하여 InZnO 버퍼층을 도입하여 박막 표면의 변화를 관찰하고자 진행하였다. 이를 위하여 펄스 레이저 증착법을 이용하였고 형성된 InZnO의 구조적 특성 평가를 위하여 X-선 회절법 및 투과 전자현미경 분석을 행하였다. 또한 표면 변화 관찰을 위하여 원자력 현미경 분석도 실시하였다. 소량의 In 첨가로 InZnO 버퍼층은 ZnO 층에 비해 표면 거칠기가 급격히 감소하여 양질의 ZnMgO/ZnO 박막을 성장하기 위한 유리한 조건을 갖추었다.

다양한 기판온도에서 성장된 ZnO 나노구조체의 버퍼층 효과

이혜지,서성보,손선영,김종재,김화민 한국물리학회 2011 새물리 Vol.61 No.1

In this study, the ZnO nano-structures were grown on Si substrates at various growth temperatures from 500 ℃ to 900℃ by using a thermal evaporation method, and the effects of Zn and ZnO buffer layers prepared by using a RF magnetron sputtering system were investigated. The surface morphology and the growth direction of the ZnO nano structures with Zn and ZnO buffer layers on Si wafers were determined by using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Among all samples, because the ZnO nano-structures grown on ZnO buffer layers at 700℃ had a ZnO (002) preferred orientation and vertical growth potential due to their acting as a seed layer, those nanostructures can be applied to optoelectronic devices. 본 연구에서, ZnO 나노구조체는 500∼900℃의 다양한 성장 온도 조건에서 열증착 방법에 의해 Si 기판위에 성장되었으며, 또한 RF-magnetron sputter에 의해 제작된 Zn와 ZnO 버퍼층의 유무에 따른 효과들을 연구하였다. Zn 및 ZnO 버퍼층을 갖는 ZnO 나노구조체의 표면 형상과 성장 방향은 SEM과 XRD 분석을 이용해 확인하였다. 제작된 샘플들 가운데 700℃에서 ZnO 버퍼층위에 성장된 ZnO 나노구조체는 nanorod 형태를 가지며 이는 ZnO 버퍼층이 seed layer로 작용함으로써 ZnO (002) 우선 배향성이 향상되었다. 또한 최적화된 조건에서 형성된 ZnO는 일정하며, 수직성장된 형상들을 갖는 것을 확인하였다. 결론적으로 최적화된 성장온도에서 버퍼층 도입에 따라 ZnO 나노구조체의 성장 제어가 수월해짐을 확인하였다. 샘플들 가운데, 700 ℃에서 ZnO 버퍼층위에 성장된 ZnO 나노 구조체는 버퍼층이 seed 층으로 작용하기 때문에 ZnO (002) 우선 성장과 수직 성장 가능성이 향상되어지고, 광전자 소자로 적용될 수 있다.

Effect of Ga-doping on the properties of ZnO f ilms grown on glass substrate at room temperature by radio frequency magnetron sputtering

G.C. Kim(김금채),S.K. Lee(이수경),J.S. Lee(이지수),D.H. Kim(김도현),S.H. Lee(이성희),J.H.Moon(문주호),M.H. Jeon(전민현) 한국진공학회(ASCT) 2008 Applied Science and Convergence Technology Vol.17 No.1

유리기판 위에 약 500 ㎚의 두께로 성장된 ZnO층의 구조적, 광학적, 전기적 성질에 미치는 갈륨도핑의 영향에 대하여 연구하였다. 다결정 ZnO 와 GZO 층은 상온에서 radio frequency magnetron sputtering 법을 사용하여 성장되었다. 투과전자 현미경 (TEM)과 x-ray 회절분석 (XRD)에 의하면, 갈륨이 도핑된 ZnO 박막의 결정성은 ZnO에 비하여 향상되었고 (002)방향을 따라 우선성장 되었음이 발견되었다. GZO 박막의 투과도는 가시광 영역에서 ZnO 박막에 비해 약 10% 정도 향상된 것으로 나타났다. PL 분석에 따르면, NBE emission 세기와 DL emission 세기의 비는 GZO 와 ZnO의 경우 각각 2.65:1 과 1.27:1로 나타났다. GZO와 ZnO의 비저항은 각각 1.27과 1.61 Ωㆍ㎝ 로서 GZO의 전기전도도가 높았다. GZO 와 ZnO의 캐리어농도는 각각 10¹? and 10²? ㎠/Vs으로 측정되었다. 본 실험결과 따르면, Ga 도핑으로 인해 ZnO 박막의 전기적, 광학적, 구조적 특성이 향상되었음을 알 수 있었다. We present the effect of Ga-doping on the electrical, structural and optical properties of ZnO layers with a thickness of ~500 ㎚ deposited on glass substrates. Polycrystalline ZnO and Ga-doped ZnO (GZO) layers were deposited by radio frequency (rf) magnetron sputtering at room temperature. Based on the X-ray diffraction (XRD) and transmission electron microscopy (TEM) data, the crystalline quality of Ga-doped ZnO film was improved and GZO film has a preferred orientation along with the (002) crystal direction. The transmittance of the GZO film was enhanced by 10% in the visible region from that of the ZnO film. From photoluminescence (PL) data, the ratio of intensity of near band edge (NBE) emission to deep level (DL) emission was as high as 2.65:1 and 1.27:1 in the GZO and ZnO films, respectively. The res istivities of GZO and ZnO films were measured to be 1.27 and 1.61 Ωㆍ㎝, respectively. The carrier concentrations of ZnO and GZO film were approximately 1018 and 1020 ㎠/Vs, respectively. Based on our experimental results, the Ga-doping improves the electrical, structural and optical properties of ZnO film with potential application.

ZnO/Cu₂O-decorated rGO: Heterojunction photoelectrode with improved solar water splitting performance

Hou, Tian-Feng,Shanmugasundaram, Arunkumar,Hassan, Mostafa Afifi,Johar, Muhammad Ali,Ryu, Sang-Wan,Lee, Dong-Weon Pergamon Press 2019 International journal of hydrogen energy Vol. No.

<P><B>Abstract</B></P> <P>In present work, we report a facile fabrication process to improve the photoelectrochemical (PEC) performance of ZnO-based photoelectrodes. In order to achieve that, the Cu<SUB>2</SUB>O nanocubes are cathodic-deposited on the as-prepared ZnO nanorods. Then rGO nanosheets are electrodeposited on the ZnO/Cu<SUB>2</SUB>O heterostructures. The fabricated photoelectrodes are systematically studied in detail by different characterization techniques such as powder X-ray diffraction, micro-Raman, X-ray photoelectron spectroscopy, ultraviolet diffused reflectance spectroscopy and photoluminescence spectroscopy analysis. Morphologies of the fabricated photoelectrodes are investigated through electron microscopy in scanning and transmission mode. To evaluate the PEC performance of the fabricated photoelectrodes, the line scan voltammetry (LSV) measurement is performed using a three-electrode system in 0.5-M Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte solution under stimulated light illumination at 100 mW/cm<SUP>2</SUP> from a 300-W Xenon Arc lamp coupled with an AM 1.5G filter using a three-electrode system. The photocurrent measurement demonstrates that the photoelectrodes based on ZnO/Cu<SUB>2</SUB>O/rGO possess enhanced PEC performance compared to the pristine ZnO and ZnO/Cu<SUB>2</SUB>O photoelectrodes. The photocurrent density of ZnO/Cu<SUB>2</SUB>O/rGO-15 photoelectrode (10.11 mA/cm<SUP>2</SUP>) is ∼9 and ∼3 times higher than the photoelectrodes based on pristine ZnO (1.06 mA/cm<SUP>2</SUP>) and ZnO/Cu<SUB>2</SUB>O (3.22 mA/cm<SUP>2</SUP>). The enhanced PEC performance of ZnO/Cu<SUB>2</SUB>O/rGO photoelectrode is attributed to the excellent light absorption properties of Cu<SUB>2</SUB>O and excellent catalytic and charge transport properties of rGO. Experimental results reveal that the proposed functional nanomaterials have a great potential in water splitting applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> rGO-protected ZnO/Cu<SUB>2</SUB>O heterojunction photoelectrodes for water splitting. </LI> <LI> Thickness of rGO on heterostructure controlled by electrochemical reduction time. </LI> <LI> Cu<SUB>2</SUB>O significantly enhances the light absorption for ZnO/Cu<SUB>2</SUB>O heterojunction. </LI> <LI> Super catalytic and charge transport properties of rGO improved the PEC performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The improved PEC performance of the ZnO/Cu<SUB>2</SUB>O/rGO hybrid photoelectrodes is attributed to (i) excellent crystalline nature of the as-prepared ZnO NRs and Cu<SUB>2</SUB>O nanocubes, (ii) large light absorption property of the Cu<SUB>2</SUB>O nanocubes, (iii) high electrical conduction effect and excellent charge transport property of the rGO nanosheets, (iv) electric effect induced by the heterojunction between the vertically aligned ZnO NRs, Cu<SUB>2</SUB>O nanocubes and rGO nanosheets (Scheme 2) and (v) excellent electron acceptor and passivation layer of rGO. All these factors coupled together contribute to the excellent PEC performance of ZnO/Cu<SUB>2</SUB>O/rGO hybrid based photoelectrodes.</P> <P>[DISPLAY OMISSION]</P>

Photocurrent detection of chemically tuned hierarchical ZnO nanostructures grown on seed layers formed by atomic layer deposition

Bang, Seokhwan,Lee, Seungjun,Ko, Youngbin,Park, Joohyun,Shin, Seokyoon,Seo, Hyungtak,Jeon, Hyeongtag Springer 2012 NANOSCALE RESEARCH LETTERS Vol.7 No.1

<P>We demonstrate the morphological control method of ZnO nanostructures by atomic layer deposition (ALD) on an Al<SUB>2</SUB>O<SUB>3</SUB>/ZnO seed layer surface and the application of a hierarchical ZnO nanostructure for a photodetector. Two layers of ZnO and Al<SUB>2</SUB>O<SUB>3</SUB> prepared using ALD with different pH values in solution coexisted on the alloy film surface, leading to deactivation of the surface hydroxyl groups. This surface complex decreased the ZnO nucleation on the seed layer surface, and thereby effectively screened the inherent surface polarity of ZnO. As a result, a 2-D zinc hydroxyl compound nanosheet was produced. With increasing ALD cycles of ZnO in the seed layer, the nanostructure morphology changes from 2-D nanosheet to 1-D nanorod due to the recovery of the natural crystallinity and polarity of ZnO. The thin ALD ZnO seed layer conformally covers the complex nanosheet structure to produce a nanorod, then a 3-D, hierarchical ZnO nanostructure was synthesized using a combined hydrothermal and ALD method. During the deposition of the ALD ZnO seed layer, the zinc hydroxyl compound nanosheets underwent a self-annealing process at 150 °C, resulting in structural transformation to pure ZnO 3-D nanosheets without collapse of the intrinsic morphology. The investigation on band electronic properties of ZnO 2-D nanosheet and 3-D hierarchical structure revealed noticeable variations depending on the richness of Zn-OH in each morphology. The improved visible and ultraviolet photocurrent characteristics of a photodetector with the active region using 3-D hierarchical structure against those of 2-D nanosheet structure were achieved.</P>

버퍼막 두께 및 버퍼막 열처리 온도에 따른 ZnO/b-ZnO/p-Si(111)의 전기적 특성 변화 및 이종접합 다이오드 특성 평가

허주회,류혁현,Heo, Joo-Hoe,Ryu, Hyuk-Hyun 한국진공학회 2011 Applied Science and Convergence Technology Vol.20 No.1

In this study, the effects of ZnO buffer layer thickness and annealing temperature on the heterojunction diode, ZnO/b-ZnO/p-Si(111), were reported. The effects of those on the structural and electrical properties of zinc oxide (ZnO) films on ZnO buffered p-Si (111) substrate were also studied. Structural properties of ZnO thin films were studied by X-ray diffraction and I-V characteristics were measured by a semiconductor parameter analyzer. ZnO thin films with 70 nm thick buffer layer and annealing temperature of $700^{\circ}C$ showed the best c-axis preferred orientation. The best electrical property was found at the condition of buffer layer annealing temperature of $700^{\circ}C$ and 50nm thick ZnO buffer layer (resistivity: $2.58{\times}10^{-4}[{\Omega}-cm]$, carrier concentration: $1.16{\times}1020[cm^{-3}]$). The I-V characteristics for ZnO/b-ZnO/p-Si(111) heterojunction diode were improved with increasing buffer layer thickness at buffer layer annealing temperature of $700^{\circ}C$.

FBAR 필터 응용을 위한 Al 하부전극 상에서 ZnO 박막 증착 및 온도가 ZnO 결정의 성장에 미치는 영향

윤기완,임문혁,채동규,Mai Linh 한국정보통신학회 2003 한국정보통신학회논문지 Vol.7 No.2

In this paper, an investigation on the ZnO film deposition using radio-frequency magnetic sputtering techniques on aluminum bottom electrode for film bulk acoustic wave resonator (FBAR) filter applications and the temperature effects on the ZnO film growth is presented. The investigation on how much impact the actual process temperature may have on the crystal growth is more meaningful if it is considered that the piezoelectricity property of ZnO films plays a dominant role in determining the resonance characteristics of FBAR devices and the piezoelectricity is determined by the degree of the c-axis preferred orientation of the deposited ZnO films. In this experiment, it was found that the growth of ZnO crystals has a strong dependence on the deposition temperature ranged from room temperature to $350^{\circ}C$ regardless of the RF powers applied and there exist 3 temperature regions divided by 2 critical temperatures according to the degree of the c-axis preferred orientation. Overall, below $200^{\circ}C$, ZnO deposition results in columnar grains with a highly preferred c-axis orientation. With this ZnO film, a multilayered FBAR structure could be realized successfully. 본 논문에서는 FBAR(film bulk acoustic wave resonator) 필터 응용을 위해 Al 하부전극 상에서 RF magnetron sputtering 기술을 이용한 ZnO 박막 증착 및 공정온도가 ZnO 결정성장에 미치는 영향에 대한 연구결과를 발표한다 ZnO 박막의 압전특성은 FBAR 소자의 공진특성을 결정하는 가장 중요한 요소이고 압전성은 증착된 ZnO박막의 c축 우선배향성의 정도에 의해 결정된다는 사실을 고려한다면 ZnO 결정성장에 미치는 공정온도에 관한 연구는 매우 의미 있는 일이다. 본 실험을 통하여 ZnO 박막의 성장특성은 상온에서부터 35$0^{\circ}C$까지의 실험조건에서 c축 우선배향성의 정도에 따라 RF power에 관계없이 온도를 2개의 임계온도에 의해 나눠진 3개의 온도구간으로 구분할 수 있었다. 결과적으로 20$0^{\circ}C$ 이하의 공정온도에서는 주상형 결정립을 가진 c축 우선배향의 ZnO 박막을 얻을 수 있었다. 이렇게 얻은 ZnO박막을 사용하여 FBAR 다층박막 구조를 구현하였다.

초음파 열분해법를 이용한 ZnO 성장

김길영,정연식,변동진,최원국,Kim, Gil-Young,Jung, Yeon-Sik,Byun, Dong-Jin,Choi, Won-Kook 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.4

단결정 사파이어 (0001) 기판 위에 저가의 초산아연(Zinc Acetate Dehydrate; ZAH) 전구체를 이용하여 초음파 열분해법과 Ar 가스를 이용한 ZnO 박막을 성장시켰다. Thermogravimetry-Differential Scanning Calorimetry(TG-DSC) 초산아연의 열분해 과정을 조사하여 $380^{\circ}C$ 이상에서 ZnO로 분해되는 것을 확인하였다. $380-700^{\circ}C$에서 증착된 ZnO 박막은 모두 ZnO (002), (101) 결정면으로 부터의 회절피크를 보여주고 있었으며, $400^{\circ}C$ 박막의 경우 c-압축 스트레인 ${\Sigma}Z=0.2\%$, 압축 응력 $\sigma=-0.907\;GPa$이 작용하고 있음을 알 수 있었다. 전자 현미경을 이용한 미세 구조의 관찰을 통하여 $380-600^{\circ}C$에서는 초산아연과 ZnO 초미세 입자가 혼합된 aggregate 형태의 결정립을 형성하고 있었으며, nanoblade 형태의 미세구조를 보였다. 한편 $700^{\circ}C$에서 증착된 박막내의 결정립은 찌그러진 육방정계의 형태를 취하고 있으며, 10-25nm 정도의 부결정림 초미세 ZnO 입자로 이루어져 있음을 알 수 있었다. 초미세 입자의 형성을 임의 핵형성 기구(random nucleation mechanism)로 설명하였고, photoluminescence(PL) 측정을 통하여 광 특성을 조사하였다. ZnO was deposited on sapphire single crystal substrate by an ultrasonic pyrolysis of Zinc Acetate Dehydrate (ZAH) with carrying Ar gas. Through Thermogravimetry-Differential Scanning Calorimetry(TG-DSC), zinc acetate dihydrate was identified to be dissolved into ZnO above $380^{\circ}C$. ZnO deposited at $380-700^{\circ}C$ showed polycrystalline structures with ZnO (101) and ZnO (002) diffraction peaks like bulk ZnO in XRD, and from which c-axis strain ${\Sigma}Z=0.2\%$ and compressive biaxial stress$\sigma=-0.907\;GPa$ was obtained for the ZnO deposited $400^{\circ}C$. Scanning electron microscope revealed that microstructures of the ZnO were dependent on the deposition temperature. ZnO grown below temperature $600^{\circ}C$ were aggregate consisting of zinc acetate and ZnO particles shaped with nanoblades. On the other hand the grain of the ZnO deposited at $700^{\circ}C$ showed a distorted hexagonal shape and was composed of many ultrafine ZnO powers of 10-25 nm in size. The formation of these ulrafine nm scale ZnO powers was explained by the model of random nucleation mechanism. The optical property of the ZnO was analyzed by the photoluminescence (PL) measurement.