Sub-bandgap pulsed laser patterning of planar chalcogenide microphotonics

Ceramic composite materials are increasingly used in dental restoration procedures, but current ceramic surface designs do not yet achieve the osseointegration potential of state-of-the-art titanium implants. Rapid bone tissue integration of an implant is greatly dependent on its surface characteristics, but the material properties of ceramic composite materials interfere with classical surface modification techniques. Here, ultra-short pulsed laser machining, which offers a defined energy input mitigating a heat-affected zone, is explored for surface modification of ceramic composites. Inspired by surface textures of clinically relevant titanium implants, dual roughness surfaces are laser patterned. Raman mapping reveals a negligible effect of ultra-short pulsed laser ablation on material properties, but a laser-induced change in the wetting state is revealed by static contact angle measurements. Laser patterning of surfaces also influences blood coagulation, but not the attachment and spreading of osteoblastic cells. The presented laser machining approach thus allows the introduction of a rational surface design on ceramic composites, holding great promise for the manufacturing of ceramic implants.

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Femtosecond pulsed laser patterning of poly(3,4-ethylene dioxythiophene)-poly(styrenesulfonate) thin films on gold/palladium substrates

Journal of Applied Physics ◽

10.1063/1.2752137 ◽

2007 ◽

Vol 102 (1) ◽

pp. 013107 ◽

Cited By ~ 12

Author(s):

Joel P. McDonald ◽

Jeffrey L. Hendricks ◽

Vanita R. Mistry ◽

David C. Martin ◽

Steven M. Yalisove

Keyword(s):

Thin Films ◽

Pulsed Laser ◽

Laser Patterning ◽

Femtosecond Pulsed Laser

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Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089652 ◽

1991 ◽

Vol 49 ◽

pp. 1068-1069

Author(s):

M. Grant Norton ◽

C. Barry Carter

Keyword(s):

Thin Film ◽

Thin Films ◽

Laser Ablation ◽

Substrate Surface ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Thin Film Deposition ◽

Film Deposition ◽

Laser Ablation Process ◽

Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

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Microstructural changes of Aluminum Nitride after laser irradiation and electroless copper deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170918 ◽

1994 ◽

Vol 52 ◽

pp. 636-637

Author(s):

S. Cao ◽

A. J. Pedraza ◽

L. F. Allard

Keyword(s):

Aluminum Nitride ◽

Laser Irradiation ◽

Electroless Deposition ◽

Thermal Evaporation ◽

Surface Region ◽

Near Surface ◽

Laser Patterning ◽

Electroless Copper ◽

Excimer Laser Irradiation ◽

Laser Effect

Excimer-laser irradiation strongly modifies the near-surface region of aluminum nitride (AIN) substrates. The surface acquires a distinctive metallic appearance and the electrical resistivity of the near-surface region drastically decreases after laser irradiation. These results indicate that Al forms at the surface as a result of the decomposition of the Al (which has been confirmed by XPS). A computer model that incorporates two opposing phenomena, decomposition of the AIN that leaves a metallic Al film on the surface, and thermal evaporation of the Al, demonstrated that saturation of film thickness and, hence, of electrical resistance is reached when the rate of Al evaporation equals the rate of AIN decomposition. In an electroless copper bath, Cu is only deposited in laser-irradiated areas. This laser effect has been designated laser activation for electroless deposition. Laser activation eliminates the need of seeding for nucleating the initial layer of electroless Cu. Thus, AIN metallization can be achieved by laser patterning followed by electroless deposition.

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