Formation manner of polycrystal silicone films and production manner null of thin film

摘要

PURPOSE: To manufacture a TRFT almost free of crystalline grain boundary in the current path in a channel region with excellent reproducibility by controlling the position of crystalline grain boundary on an insulating substrate as well as arranging the orientation degree of individual crystalline grains to form polycrystalline silicon film in large grain diameter. CONSTITUTION: The first polycrystalline silicon film 4 arranged with orientation degree in the vertical direction to the stepped part side 7 is obtained by forming the first amorphous silicon 3 film on an insulating substrate 1 formed of a stepped part 2 to be heat-treated. Next, the whole surface is patterned leaving the region containing the part above the stepped part 2. Next, the second amorphous silicon film 8 is formed on the pattern and the first polycrystalline silicon film 4 is used as a seed to solid crystallize so that the orientation degree and the position of crystalline grain boundary controlling the second polycrystalline silicon film 9 may be formed. Finally, when a channel region 12i formed making the vertical direction to the side of the stepped part 2, a current path may be coincide with the epitaxial growing direction.