Retention characteristics of Pb(Zr, Ti)O3 films deposited by various methods for high-density non-volatile memory

ABSTRACTRetention loss is a significant issue for an application of ferroelectric thin films to high-density non-volatile memory devices. We investigated the polarization retention characteristics of ferroelectric Pb(Zr,Ti)O3 (PZT) thin films which were fabricated on Pt/IrO2/Ir substrates by different deposition methods. In thermally-accelerated retention failure tests, Pb(Zr,Ti)O3 (PZT) films which were prepared by a chmeical solution deposition (CSD) method showed rapid decay of retained polarization charges as the films became thinner down to 1000 Å, while the films which were grown by metal organic chemical vapor deposition (MOCVD) showed relatively large nonvolatile charges at the same thickness. We concluded that in the CSD-grown films, the relatively large interfacial passive layer compared with the MOCVD-grown films had an unfavorable effect on retention behavior. We observed the existence of such interfacial layers by extrapolation of the total capacitance with thickness of the films and the capacitance of this layer was larger in MOCVD-grown films. It means that the possibility of the accumulation of space charges at the interface was reduced, so that less imprint and less retention loss could be observed in the MOCVD-grown films.

Download Full-text

{10} edge dislocations in YSZ films grown on (100)MgO by PLD

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170384 ◽

1994 ◽

Vol 52 ◽

pp. 530-531

Author(s):

Jason R. Heffelfinger ◽

C. Barry Carter

Keyword(s):

Thin Films ◽

Semiconductor Lasers ◽

Vapor Deposition ◽

Substrate Surface ◽

Laser System ◽

Average Energy ◽

Target Material ◽

Chemical Vapor ◽

Buffer Layers ◽

Organic Chemical

Yttria-stabilized zirconia (YSZ) is currently used in a variety of applications including oxygen sensors, fuel cells, coatings for semiconductor lasers, and buffer layers for high-temperature superconducting films. Thin films of YSZ have been grown by metal-organic chemical vapor deposition, electrochemical vapor deposition, pulse-laser deposition (PLD), electron-beam evaporation, and sputtering. In this investigation, PLD was used to grow thin films of YSZ on (100) MgO substrates. This system proves to be an interesting example of relationships between interfaces and extrinsic dislocations in thin films of YSZ.In this experiment, a freshly cleaved (100) MgO substrate surface was prepared for deposition by cleaving a lmm-thick slice from a single-crystal MgO cube. The YSZ target material which contained 10mol% yttria was prepared from powders and sintered to 85% of theoretical density. The laser system used for the depositions was a Lambda Physik 210i excimer laser operating with KrF (λ=248nm, 1Hz repetition rate, average energy per pulse of 100mJ).

Download Full-text

Growth of gallium oxide thin films on silicon by the metal organic chemical vapor deposition method

Materials Science and Engineering B ◽

10.1016/j.mseb.2004.01.012 ◽

2004 ◽

Vol 110 (1) ◽

pp. 34-37 ◽

Cited By ~ 47

Author(s):

Hyoun Woo Kim ◽

Nam Ho Kim

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Gallium Oxide ◽

Chemical Vapor ◽

Organic Chemical ◽

Chemical Vapor Deposition Method ◽

Deposition Method ◽

Metal Organic ◽

Organic Chemical Vapor Deposition

Download Full-text

Observations on the Growth of YBa2Cu3O7 Thin Films at Very High Laser Fluences

MRS Proceedings ◽

10.1557/proc-388-67 ◽

1995 ◽

Vol 388 ◽

Cited By ~ 2

Author(s):

Rand R. Biggers. ◽

M. Grant Norton ◽

I. Maartense ◽

T.L. Peterson ◽

E. K. Moser ◽

...

Keyword(s):

Thin Films ◽

Substrate Surface ◽

Chemical Vapor ◽

Growth Conditions ◽

Organic Chemical ◽

High Fluences ◽

Laser Fluences ◽

High Laser ◽

High Laser Fluences ◽

Very High

AbstractThe pulsed-laser deposition (PLD) technique utilizes one of the most energetic beams available to form thin films of the superconducting oxide YBa2Cu3O7 (YBCO). IN this study we examine the growth of YBCO at very high laser fluences (25 to 40 J/cm2); a more typical fluence for PLD would be nearer to 3 J/cm2. the use of high fluences leads to unique film microstructures which, in some cases, appear to be related to the correspondingly higher moveabilities of the adatoms. Films grown on vicinal substrates, using high laser fluences, exhibited well-defined elongated granular morphologies (with excellent transition temperature, Tc, and critical current density, Jc). Films grown on vicinal substrates using off-axis magnetron sputtering, plasma-enhanced metal organic chemical vapor deposition (PE-MOCVD), or PLD at more typical laser fluences showed some similar morphologies, but less well-defined. Under certain growth conditions, using high laser fluences with (001) oriented substrates, the YBCO films can exhibit a mixture of a- and c-axis growth where both crystallographic orientations nucleate on the substrate surface at the same time, and grow in concert. the ratio of a-axis oriented to c-axis oriented grains is strongly affected by the pulse repetition rate of the laser.

Download Full-text

Domain structure of epitaxial PbTiO3 thin films on LaAlO3(100) grown by metal organic chemical vapor deposition

Journal of Applied Physics ◽

10.1063/1.369203 ◽

1999 ◽

Vol 85 (2) ◽

pp. 853-860 ◽

Cited By ~ 12

Author(s):

Bi Ming Yen ◽

Haydn Chen

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Domain Structure ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Metal Organic ◽

Organic Chemical Vapor Deposition

Download Full-text

Properties of Tin Oxide Films Prepared by MOCVD

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.997 ◽

2004 ◽

Vol 449-452 ◽

pp. 997-1000 ◽

Cited By ~ 3

Author(s):

Gwang Pyo Choi ◽

Yong Joo Park ◽

Whyo Sup Noh ◽

Jin Seong Park

Keyword(s):

Thin Films ◽

Oxygen Content ◽

Tin Oxide ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Metal Organic ◽

Organic Chemical Vapor Deposition ◽

Tin Oxide Films ◽

N2 Annealing

Tin oxide thin films were deposited at 375 °C on α-alumina substrate by metal-organic chemical vapor deposition (MOCVD) process. A number of hillocks on the film were formed after air annealing at 500 °C for 30 min and few things in N2 annealing. The oxygen content and the binding energy after air annealing came to close the stoichiometric SnO2. The cauliflower hillocks of the film seem to be formed by the continuous migration of crystallites from a cauliflower grain on the substrate to release the stress due to the increase of oxygen content and volume.

Download Full-text