Laser Direct Writing of Aluminum Conductor Lines from a Liquid Phase Precursor

Aluminum conductor lines were deposited on Si substrates from liquid phase triisobutylaluminum (TIBA) using a scanned argon ion laser. The vertical growth rate of Al lines initially increased, then decreased with increasing dwell time. The maximum vertical growth rate occurred at a particular dwell time depending upon the laser power. Lower vertical growth rates at longer dwell times are probably caused by the depletion of the reactant at the reaction site. A volcano deposit shape was observed, which became more pronounced as dwell time increased. The conductivity of the as-deposited Al lines decreased with increasing dwell time for our experimental conditions. To study the deposition kinetics and calculate the activation energy, the temperature rise on the Si surface was calculated by solving the nonlinear heat equation using finite difference method.