Semiconductor device having a laser annealed semiconductor layer

摘要

A laser annealing method includes forming a nitrogen-doped layer on a semiconductor layer, the nitrogen-doped layer having a nitrogen concentration of at least 3×1020 atoms/cc, irradiating a first area of the nitrogen-doped layer in a low oxygen environment with a laser beam and irradiating a second area of the nitrogen-doped layer in a low oxygen environment with a laser beam, a part of the second area overlapping with the first area.

主权项

1. A semiconductor device comprising:
a laser-annealed semiconductor layer comprising a first polycrystalline silicon layer, and a second polycrystalline silicon layer integrally formed on the first polycrystalline silicon layer and doped with nitrogen, the laser-annealed semiconductor layer comprising a first area laser-annealed and a second area laser-annealed wherein a part of the first area overlaps with a part of the second area in a direction perpendicular to a surface of the laser-annealed semiconductor layer and the overlap region is laser-annealed by two times, the laser-annealed semiconductor layer having a nitrogen concentration of at least 3×1020 atoms/cc on the second polycrystalline silicon layer and a root mean square (rms) value of grain protrusion height is less than 20nm.