Methods for thermal treatment of a semiconductor layer in semiconductor device

A method for thermal treatment on a semiconductor device, comprising:

• obtaining a pattern of a treatment area comprising amorphous silicon;
• aligning a plurality of laser beams with the treatment area, the laser beams each in a focused laser spot having a plurality of spot areas each less than or equal to a treatment area;
• and
• performing a laser anneal on the treatment area by emitting the plurality of laser beams towards the treatment area for a treatment period to convert the amorphous silicon to polysilicon,
• wherein:
• a spot area of the plurality of spot areas comprises a central spot area and a peripheral spot area surrounding the central spot area;
• and
• a dimension of the treatment area is at least related to a dimension of the central spot area, a width of a scribe line, and an overlay error.

A system for thermal treatment on a semiconductor device, comprising:

• a laser source configured to generate one or more laser beams;
• an optical module configured to provide one or more focused laser spots on a treatment area;
• and
• a controller coupled to the optical module and configured to (i) obtain dimensions of the treatment area, and (ii) control at least the optical module to perform a laser anneal on the treatment area by applying the one or more focused laser spots on treatment area based on a spot area of each of the focused laser spots and the treatment area,
• wherein:
• the spot area comprises a central spot area and a peripheral spot area surrounding the central spot area;
• and
• a dimension of the spot area is at least related to a dimension of the treatment area, a dimension of the peripheral spot area, and an overlay error.