• 제목/요약/키워드: (100) perovskite

검색결과 146건 처리시간 0.024초

Orientation Control and Dielectric Properties of Sol-gel Deposited (Ba,Sr)TiO3 Thin Films for Room-temperature Tunable Element Applications

  • Zhai, Jiwei;Chen, Haydn
    • 한국세라믹학회지
    • /
    • 제40권4호
    • /
    • pp.380-384
    • /
    • 2003
  • The effects of the mole concentrations of precursor solution on the microstructure and dielectric properties of sol-gel deposited $Ba_{0.85}$S $r_{0.15}$Ti $O_3$(BST) thin films have been investigated. The films were of single perovskite phase with strong (100) preferred orientation when grown on LaNi0$_3$ buffered Pt/Ti/ $SiO_2$Si substrates using a diluted precursor solution. Variation of the precursor solution concentration resulted in a different microstructure and, in turn, affected the tunability of the sol-gel deposited films. It was observed that leakage currents increased asymmetrically for the negative and positive bias voltage with decreasing thickness. Overall results suggest that those BST films have acceptable properties f3r applications as room-temperature tunable elements.

Seeding층이 sol-gel법에 의한 PLZT 박막의 제조시 전기적 특성에 미치는 영향 (Effects of seeding layers on electrical properties of PLZT thin films prepared by sol-gel method)

  • 이진홍;박병욱
    • 한국결정성장학회지
    • /
    • 제10권2호
    • /
    • pp.140-144
    • /
    • 2000
  • ($Pb_{0.91}$$La_{0.09}$)($Zr_{0.65}$$Ti_{0.35}$)$O_3$ thin films were prepared on ITO-coated glass by spin-coating. As $Pb_{0.9}$$La_{0.1}$)$TiO_3$ thin films were used as seeding layers, formation temperature of perovskite was reduced and theUrosette" structure was disappeared. PLZT thin films with a seeding layer of 40 nm thick showed a (100) preferred orientation and better dielectric and ferroelectric properties.ties.

  • PDF

Control the crystal size by varying concentrations of precursors for the planar perovskite solar cells

  • Xie, Lin;Hwang, Heewon;Kim, Minjung;Kim, Kyungkon
    • Rapid Communication in Photoscience
    • /
    • 제4권4호
    • /
    • pp.79-81
    • /
    • 2015
  • The influence of the grain size of the $CH_3NH_3PbI_3$ on the solar cell performance is investigated by controlling the ratio between $CH_3NH_3I$ and $PbI_2$ precursors. As the concentration of the precursors increased from 1.0M to 2.0M, the $CH_3NH_3PbI_3$ grain size increased from ~100nm to ~400nm. The solar cell utilizing the $CH_3NH_3PbI_3$ with large grain size shows improved photocurrent compared to the solar cell utilizing $CH_3NH_3PbI_3$ with small grain size, which is ascribed to the reduced recombination at the boundaries of grains.

소결온도에 따른 $Ba(Zn_{1/3}Ta_{2/3})O_3$[BZT] 세라믹스의 구조적 특성 (Structural Properties of $Ba(Zn_{1/3}Ta_{2/3})O_3$[BZT] Ceramics with Sintering Temperature)

  • 이상철;김지헌;김강;이성갑;이영희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
    • /
    • pp.76-79
    • /
    • 2000
  • The $Ba(Zn_{1/3}Ta_{2/3})O_3$ ceramics were prepared by conventional mixed oxide method. The structural properties of the BZT ceramics with the sintering temperature were investigated by XRD, SEM. The BZT ceramics have a complex-perovskite structure. The BZT ceramics sintered at $1550^{\circ}C$ had a superstructure plane of BZT(100). Increasing the sintering temperature, the bulk density and ordering were increased. The bulk density of the BZT ceramics sintered at $1550^{\circ}C$ was $7.50[g/cm^3]$. Increasing the sintering temperature, the average grain size were increased and pore were decreased.

  • PDF

Plasma source와 RF power에 따른 NiO박막의 우선배향성 및 표면형상 (The Evolution of Preferred Orientation and Morphology of NiO Thin Films under Variation of Plasma Source and RF Power)

  • Hyunwook Ryu;Park, Jinseong
    • 한국재료학회:학술대회논문집
    • /
    • 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
    • /
    • pp.121-121
    • /
    • 2003
  • NiO thin films are very attractive for use as an antiferromagnetic layer, p-type transparent conducting films, in electrochromic devices and functional sensor layer for chemical sensors, due to their excellent chemical stability, as well as optical, electrical and magnetic properties. In addition, (100)- and (111)-oriented NiO films can be used as buffer layers on which to deposit other oriented oxide films, such as c-axis-oriented perovskite-type ferromagnetic films and superconducting films, because of the similarity in symmetry of oxygen ion lattice and lattice constants between the NiO films and the oriented oxide films. Thus, controlling the crystallographic orientation and surface roughness of the NiO films for a buffer layer are very important.

  • PDF

알루미나 기판에 스크린 프린팅된 Ag(Ta,Nb)O3 후막의 유전특성 및 초고주파 특성에 대한 연구 (An Investigation on the Dielectric and Microwave Properties of Ag(Ta,Nb)O3 Thick Films on the Alumina Substrates)

  • 이규탁;고중혁
    • 한국전기전자재료학회논문지
    • /
    • 제24권11호
    • /
    • pp.925-928
    • /
    • 2011
  • Perovskite niobates and tantalates have been placed on a short list of functional materials for future technologies. This article was investigated ferroelectric materials $Ag(Ta,Nb)O_3$ thick film. In this study, we have fabricated the $Ag(Ta,Nb)O_3$ thick film on the $Al_2O_3$ substrates by screen printing method. The $Ag(Ta,Nb)O_3$ thick film were fabricated by the mixed oxide method. The sintering temperature and time were 1,150$^{\circ}C$, 2 hr. The electrical properties of $Ag(Ta,Nb)O_3$ thick film were investigated at 30~100$^{\circ}C$.

FRAM 응용을 위한 BLT 박막의 제작 및 특성 (A Fabrication and ferroelectric properties of BLT Thin Films for FRAM)

  • 김경태;권지운;심일운;김창일
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
    • /
    • pp.565-568
    • /
    • 2001
  • We have fabricated $Bi_{3.25}La_{0.75}Ti_{3}O_{12}(BLT)$ thin(200nm) films on the $Pt/Ti/SiO_{2}/Si$ substrates using a MOD(Metalorganic decomposition) method with annealing temperature from $550^{\circ}C$ to $750^{\circ}C$. The structural properties of the films examined by x-ray diffraction. The layered-perovskite phase obtained above $600^{\circ}C$. Scanning electron micrographs showed uniform surface composed of rodlike grains. The grain size increased with increasing annealing temperature. The BLT thin films showed little polarization fatigue test up to $3.5{\times}10^{9}$ bipolar cycling at a 5V and 100kHz.

  • PDF

강유전체 메모리용 $Bi_{3.3}Eu_{0.7}Ti_3O_{12}$ 박막의 증착과 전기적 특성 (Preparation and Electrical Properties of Ferroelectric $Bi_{3.3}Eu_{0.7}Ti_3O_{12}$ Thin Films for Memory Applications)

  • 강동균;박원태;김병호
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
    • /
    • pp.39-40
    • /
    • 2005
  • Ferroelectric Eu-substituted $Bi_4Ti_3O_{12}$ (BET) thin films with a thickness of 200 nm were deposited on Pt(111)/Ti/SiO$_2$/Si(100) substrate by means of the liquid delivery MOCVD system and annealed at several temperatures in an oxygen atmosphere. At annealing temperature above $600^{\circ}C$, the microstructure of layered perovskite phase was observed. The remanent polarization of these films increased with increase in annealing temperature. The remanent polarization values ($2P_r$) of the BET thin films annealed at $720^{\circ}C$ were $37.71{\mu}C/cm^2$ at an applied voltage of 5 V.

  • PDF

Chemical Solution Deposition 방법으로 증착된 $Bi_{0.8}A_{0.2}FeO_3$ (A=Pb, Co) 박막의 자기적 특성에 대한 연구

  • 차정옥;안정선
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
    • /
    • pp.245-245
    • /
    • 2011
  • $BiFeO_3$ (BFO)박막에 전위금속 Pb와 Co를 각각 치환환 박막을 chemical solution deposition 방법으로 Pt/Ti/SiO2/Si(100) 기판위에 증착하였다. Bi 자리에 Pb와 Co를 20 at.% 치환하였으며, 치환된 $Bi_{0.8}Pb_{0.2}FeO_3$ (BPFO), $Bi_{0.8}Co_{0.2}FeO_3$ (BCFO) 박막의 구조적, 자기적 특성 변화를 BFO 박막과 비교하여 조사하였다. XRD 패턴을 분석한 결과 BPFO, BCFO 박막들은 모두 rhombohedrally distorted perovskite 구조였으며 불순물인 pyrochlore 상이 약하게 관측되었다. 치환이 이루어진 BPFO, BCFO 박막들의 자기 이력곡선은 안정된 포화곡선을 나타냈으며 BFO의 포화값(5 emu/$cm^3$)에 비해 크게 증가된 55 emu/$cm^3$, 35 emu/$cm^3$의 값을 나타냈다. 또한 보자력장(coercive field, Hc)값도 BFO의 500 Oe보다 크게 증가된 1,200 Oe, 800 Oe의 값을 보였다.

  • PDF

Dielectric, Pyroelectric and Piezoelectric Properties of 0.7PMN-0.3PT Ceramics Modified With Cr$_2$O$_3$

  • Hyun, June-Won
    • 한국표면공학회지
    • /
    • 제36권5호
    • /
    • pp.413-417
    • /
    • 2003
  • The effect of 0-0.7 ㏖% addition of $Cr_2$$O_3$on the dielectric, pyroelectric, and piezoelectric properties were studied in the (Mg$0.7Pb_{1}$$3/Nb_{2}$3/)$O_3$-$0.3PbTiO_3$(0.7PMN-0.3PT) ceramics with composition near the morphotropic phase boundary. The dielectric constant and loss of the ceramics samples were measured as a function of temperature at various frequencies (0.1-100 KHz). The pyroelectric coefficient was measured by using the Byer-Roundy method as a function of temperature. Dielectric, pyroelectric, and piezoelectric constant achieved the maximum values of 0.4 ㏖% $Cr_2$$O_3$The transition temperature is continuously shifted to lower temperature with an increase of a small amount of $Cr_2$$O_3$.