A method of increasing a quality factor for a micromechanical resonator uses a laser beam to anneal the micromechanical resonator. In one embodiment, the micromechanical oscillator is formed by fabricating a mushroom shaped silicon oscillator supported by a substrate via a pillar. The laser beam is focused on a periphery of the mushroom shaped silicon oscillator to modify the surface of the mushroom shaped silicon oscillator. In a further embodiment, the mushroom shaped oscillator is a silicon disk formed on a sacrificial layer. Portions of the sacrificial layer are removed to free the periphery of the disk and leave a supporting pillar at the center of the disk. In further embodiments, different type resonators may be used.