Modeling of cw laser annealing of multilayer structures

Rapid electrokinetic patterning (REP) is an emerging optoelectric technique that takes advantage of laser-induced AC electrothermal flow and particle-electrode interactions to trap and translate particles. The electrothermal flow in REP is driven by the temperature rise induced by the laser absorption in the thin electrode layer. In previous REP applications 350-700 nm indium tin oxide (ITO) layers have been used as electrodes. In this study, we show that ITO is an inefficient electrode choice as more than 92% of the irradiated laser on the ITO electrodes is transmitted without absorption. Using theoretical, computational, and experimental approaches, we demonstrate that for a given laser power the temperature rise is controlled by both the electrode material and its thickness. A 25-nm thick Ti electrode creates an electrothermal flow of the same speed as a 700-nm thick ITO electrode while requiring only 14% of the laser power used by ITO. These results represent an important step in the design of low-cost portable REP systems by lowering the material cost and power consumption of the system.

show abstract

“…Following the procedure adopted by Calder , Eqs. and are solved for the temperature rise

Δ T_{1} (r, z)

Δ T_{1} (r, z) = \frac{P w α^{2} (1 - R)}{π k_{1}} \int_{0}^{\infty} \frac{exp (- \frac{λ^{2}}{4}) J_{0} (\frac{λ r}{w})}{2 ({(α w)}^{2} - λ^{2})} [\begin{matrix} left \frac{A (λ) + B (λ)}{C (λ)} \\ left - D (λ) \end{matrix}] d λ,

where

A (λ) = (k_{1} / k_{2}) cosh (λ (z_{1} - z) / w) + sinh (λ (z_{1} - z) / w),

B (λ) = (λ / α w - k_{1} / k_{2}) exp (- α z_{1}) cosh (λ z / w),

C (λ) = cosh (λ z_{1} / w) +

…”

Section: Theorymentioning

confidence: 99%

“…In the above equation

Δ T_{1} (r, z) = T_{1} (r, z) - T_{\infty}

T_{\infty}

is the ambient temperature and λ is the variable of integration. Readers are referred to the work of Lax and Calder for more details on derivation of Eq. .…”

Section: Theorymentioning

confidence: 99%

Optoelectric patterning: Effect of electrode material and thickness on laser‐induced AC electrothermal flow

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Com a sofisticado crescente de diversas áreas científicas e tecnológicas, há a necessidade de um estudo detalhado de como a radiagáo láser interage com materiais estratificados. Necessidade que fica evidente ao analisarmos os diversos casos que existem na literatura científica de amostras de varias carnadas de materiais que sao irradiados com láser como por exemplo: discos de gravagáo ótica (1-3) que possuem quatro carnadas, (substrato, carnada absorvedora do láser, carnada de gravagáo, carnada protetora); aquecimento e fusáo de filmes finos sobre substratos isolantes (4); implantado de ions e impurezas sobre semicondutores (5); crescimento de cristais (5,6); recozimento de semicondutores (*) Dep. Ciencia Física, Univ.…”

Section: Introdujounclassified

Aquecimento de materiais estratificados com laser pulsado de Nd:YAG

Neto

1998

REVMETAL

View full text Add to dashboard Cite

Resumo Em nosso trabalho examinamos o aquecimento de amostras compostas de duas e tres carnadas, condutor-isolante e condutor-condutor, com um pulso potente de láser. O comportamento transiente da distribuigáo de temperatura através da amostra foi calculado. Em nosso modelo de calculo para o processo de aquecimento levamos em conta a dependencia com a temperatura dos parámetros térmicos (difusividade, capacidade e condutividade térmica), óticos (refletividade e coeficiente de absorcao), bem como a dependencia das condicóes de contorno com o tempo e consequentemente com a temperatura. Aplicamos nossa metodología para calcular o aquecimento amostras compostas: Al-Au, Al-Ag, A1-A1 2 0 3 , Al-Au-Ag e Ag-Au-Al. Concluimos que o substrato influencia as temperaturas máximas ñas superficie exposta ao láser e a forma com que a frente de calor se propaga ñas amostras térmicamente finas.

show abstract

“…The examples are the doping of plane surfaces or the deposition of homogeneous films. In such cases analytical and numerical solutions [5][6][7][8][9] can be applied, some of them include multilayer structures, 10 different shapes of the energy beam, 11 temperature dependent material parameters, melting, etc.…”

Section: Introductionmentioning

confidence: 99%

Temperature distributions and their evolution in non-planar energy beam microprocessing: A fast algorithm

Arnold

1996

Journal of Applied Physics

View full text Add to dashboard Cite

We present a fast algorithm for calculations of the temperature distributions induced by the energy beam in the three-dimensional deposits of arbitrary shape. It combines analytical approximations, numerical fast Fourier transform, and the multigrid technique. The accuracy of the method is demonstrated with problems that can be solved analytically. The behavior of the center temperature in laser-deposited spots and stripes of different shapes and sizes is studied. The results can explain explosive growth in laser-induced deposition and instabilities in laser direct writing, and provide a tool for a quantitative analysis of energy beam microprocessing.

show abstract

Modeling of cw laser annealing of multilayer structures

Cited by 65 publications

References 10 publications

Optoelectric patterning: Effect of electrode material and thickness on laser‐induced AC electrothermal flow

Optoelectric patterning: Effect of electrode material and thickness on laser‐induced AC electrothermal flow

Aquecimento de materiais estratificados com laser pulsado de Nd:YAG

Temperature distributions and their evolution in non-planar energy beam microprocessing: A fast algorithm

Contact Info

Product

Resources

About