Abstract: An ignition method of a plasma chamber includes steps of: (a) starting softly an ignition voltage to a first voltage, (b) decreasing the magnitude of the ignition voltage to a second voltage after a first ignition time, (c) increasing the magnitude of the ignition voltage to the first voltage after a second ignition time, and (d) repeating the step (b) and the step (c) until the ignition is successful.

Abstract: An ignition method of a plasma chamber includes steps of: (a) starting softly an ignition voltage to a first voltage, (b) decreasing the magnitude of the ignition voltage to a second voltage after a first ignition time, (c) increasing the magnitude of the ignition voltage to the first voltage after a second ignition time, and (d) repeating the step (b) and the step (c) until the ignition is successful.

Abstract: A method for forming a label image on an optical disk is provided. A label image is formed on a label layer of an optical disk by an optical disk drive. The label layer has a number of virtual tracks including a first virtual track and a second virtual track adjacent to each other. The optical disk drive includes an optical pickup head and a spindle. The optical pickup head has a laser diode. The method includes following steps. Firstly, the optical disk is deposed around the spindle, and the label layer faces the optical pickup head. Next, the optical disk is rotated, and the laser diode is moved between the first virtual track and the second virtual track, so that a laser beam emitted by the laser diode is focused on the label layer and that a spot is formed between the first virtual and the second virtual track.