Abstract: Provided is a heat treatment device including: a laser oscillator configured to produce a laser; one or more optical systems each configured to irradiate an object to be treated with the laser produced from the laser oscillator; and a rotating table on which the object is to be mounted. When a reaching temperature of the object, at which an activation rate of the object reaches a target value through one-time irradiation with the laser, is set as a first temperature, a second temperature lower than the first temperature is set as a target value of the reaching temperature of the object, and the object is repeatedly irradiated with the laser from one of the one or more optical systems two or more times.

Abstract: A heat treatment apparatus includes a laser oscillation unit, a stage, an optical system, and a moving unit. The laser oscillation unit oscillates laser light. The stage holds an irradiation target to be irradiated with the laser light. The optical system guides the laser light to the irradiation target. The moving unit relatively changes the positional relationship between the optical system and the irradiation target. Furthermore, the heat treatment apparatus includes a detection unit and a determination unit. The detection unit detects the power of first reflected light that is the laser light reflected from the surface of the irradiation target. On the basis of a detection value of the power of the first reflected light detected by the detection unit, the determination unit determines the presence or absence of a change in the surface temperature of an area irradiated with the laser light on the irradiation target.