Semiconductor manufacturing device and beam-shaping mask

Abstract

A manufacturing method of a semiconductor thin film decreases the number of and controls the direction of crystal grain boundaries. A first beam irradiated onto amorphous silicon produces a radial temperature gradient centered on a tip of a concave. This forms a crystal grain in the concave tip, which grows in both the beam width and length direction. After the second beam and on, growth is repeated using the crystal grain formed in the tip of the concave as the seed. This forms a band-form crystal grain with a wider than that of the conventional narrow-line beam, with the tip of the concave being the start point. Further, by setting the periphery of the concave pattern to be equal or less than the crystal grain diameter in the direction vertical to the beam scanning direction, it is possible to form the band-form crystal grain being lined continuously.

1 . A beam shaping mask for shaping a laser beam used for growing on a semiconductor thin film, wherein
 a main body of the mask has a continuous transmission region for transmitting the laser beam, said transmission region including at least one control pattern inwardly extending into the transmission region, said control pattern defining an area shielding the laser beam, the control pattern is shaped into a concave shape with respect to an edge of the transmission pattern.   
   
   
       2 . The beam shaping mask according to  claim 1 , wherein the transmission region is formed in a shape which is a rectangle and also has the control pattern extending into the rectangle at a side of the rectangle. 
   
   
       3 . The beam shaping mask according to  claim 1 , wherein the control pattern is formed in a side opposite to a side without the control pattern. 
   
   
       4 . The beam shaping mask according to  claim 1 , wherein a concave length in a length direction of the control pattern is set to be equal or less than a concave width in a width direction of the control pattern where a crystal growth width of a band-form crystal grain becomes the maximum. 
   
   
       5 . The beam shaping mask according to  claim 1 , wherein a concave width in a width direction of the control pattern is set to be equal or more than a concave width in a width direction, of the control pattern where a crystal growth width of a band-form crystal grain becomes the maximum. 
   
   
       6 . The bean shaping mask according to  claim 2 , wherein more than one control pattern is shaped in the side of the rectangle. 
   
   
       7 . The beam shaping mask according to  claim 6 , wherein a cycle of shaping the control pattern is set to be equal or less than a length which is substantially same as a crystal growth width of a band-form crystal grain. 
   
   
       8 . The beam shaping mask according to  claim 1 , wherein the concave pattern is in a shape with three or more side. 
   
   
       9 . The beam shaping mask according to  claim 1 , wherein the concave pattern is in a shape with a curve. 
   
   
       10 . The beam shaping mask according to  claim 1 , wherein the sum of beam concave lengths of each concave pattern is shorter than a length of the beam. 
   
   
       11 . The beam shaping mask according to  claim 1 , wherein the concave patterns are shaped into a plurality of different sizes or into a different shapes. 
   
   
       12 . The beam shaping mask according to  claim 2 , wherein, provided that an opening width in a width direction of the transmission region is A, a concave width in a width direction of the shielding pattern is B, and the maximum crystal growth distance of the band-form crystal grain in the width direction is L, their dimensional relation is set to be 2L≦A−B. 
   
   
       13 . The beam shaping mask according to  claim 2 , wherein provided that a concave length in a length direction of the shielding pattern is C, a convex length which is a space in between the shielding pattern is D, and the maximum crystal growth distance of the band-form crystal grain in the width direction is L, their dimensional relation is set to be 2L≧C+D. 
   
   
       14 . The beam shaping mask according to  claim 2 , wherein, provided that an opening width in a width direction of the transmission region is A, a concave width in a width direction of the shielding pattern is B, a concave length in a length direction of the shielding pattern is C, a convex length which is a space in between the shielding pattern is D, their dimensional relation is set to be A−B≧C+D. 
   
   
       15 . A semiconductor thin film manufacturing device for growing a crystal grains on a precursor film by irradiating a laser beam onto the precursor made by a semiconductor thin film formed on an insulating substrate, the device comprising a beam shaping mask for shaping a laser beam, wherein
 a main body of the mask has a continuous transmission region for transmitting the laser beam, said transmission region including at least one control pattern inwardly extending into the transmission region, said control pattern defining an area shielding the laser beam, the control pattern is shaped into a concave shape with respect to an edge of the transmission pattern.