Semiconductor device and method of manufacturing the same

Abstract

A first shape of semiconductor region having on its one side a plurality of sharp convex top-end portions is formed first and a continuous wave laser beam is used for radiation from the above region so as to crystallize the first shape of semiconductor region. A continuous wave laser beam condensed in one or plural lines is used for the laser beam. The first shape of semiconductor region is etched to form a second shape of semiconductor region in which a channel forming region and a source and drain region are formed. The second shape of semiconductor region is disposed so that a channel foaming range would be formed on respective crystal regions extending from the plurality of convex end portions. A semiconductor region adjacent to the channel forming region is eliminated.

1 . A semiconductor device comprising:
 a crystalline semiconductor film having a plurality of rectangular semiconductor regions disposed in parallel wherein the plurality of rectangular semiconductor regions continuously connected in series and a pair of semiconductor regions are connected to both ends of the plurality of rectangular semiconductor regions are continuously connected in series; and   an electrode crossing the plurality of rectangular semiconductor regions with an insulating film interposed therebetween,   wherein a channel region is formed in a crossing portion of the electrode and each of the plurality of rectangular semiconductor regions, and   wherein a crystal of the crystalline semiconductor film extends along a channel length direction.   
     
     
         2 . The semiconductor device according to  claim 1 , wherein each of the plurality of rectangular semiconductor regions comprises a channel forming region and an LDD region. 
     
     
         3 . The semiconductor device according to  claim 1 , wherein the electrode is applied with common potential. 
     
     
         4 . The semiconductor device according to  claim 1 , wherein a length of each of the plurality of rectangular semiconductor regions in a channel width direction is 0.5 to 1.0 μm. 
     
     
         5 . A semiconductor device comprising:
 a crystalline semiconductor film having a plurality of rectangular semiconductor regions disposed in parallel wherein the plurality of rectangular semiconductor regions continuously connected in series and a pair of semiconductor regions are connected to both ends of the plurality of rectangular semiconductor regions are continuously connected in series; and   an electrode crossing the plurality of rectangular semiconductor regions with an insulating film interposed therebetween,   wherein a channel region is formed in a crossing portion of the electrode and each of the plurality of rectangular semiconductor regions, and   wherein a crystal orientation aligns in the channel forming regions.   
     
     
         6 . The semiconductor device according to  claim 5 , wherein each of the plurality of rectangular semiconductor regions comprises a channel forming region and an LDD region. 
     
     
         7 . The semiconductor device according to  claim 5 , wherein the electrode is applied with common potential. 
     
     
         8 . The semiconductor device according to  claim 5 , wherein a length of each of the plurality of rectangular semiconductor regions in a channel width direction is 0.5 to 1.0 μm. 
     
     
         9 . A method for manufacturing a semiconductor device, comprising the steps of:
 forming a first semiconductor film on an insulating surface, the first semiconductor film having a first edge and a second edge opposed to each other wherein a side surface of the first edge has at least a first projection and a second projection;   scanning the first semiconductor film with a continuous wave laser beam in a direction from the first edge to the second edge in order to crystallize or improve crystallinity of the first semiconductor film wherein the crystallized first semiconductor film includes at least a first crystalline region of which crystallization occurred from the first projection and a second crystalline region of which crystallization occurred from the second projection;   forming at least a first channel region and a second channel region in the first crystalline region and the second crystalline region, respectively,   wherein at least a portion of the first semiconductor film between the first channel region and the second channel region is removed by etching.   
     
     
         10 . A method for manufacturing a semiconductor device, comprising the steps of:
 forming a first semiconductor film on an insulating surface, the first semiconductor film having a first edge and a second edge opposed to each other wherein a side surface of the first edge has at least a first projection and a second projection;   scanning the first semiconductor film with a continuous wave laser beam in a direction from the first edge to the second edge in order to crystallize or improve crystallinity of the first semiconductor film wherein the crystallized first semiconductor film includes at least a first crystalline region of which crystallization occurred from the first projection and a second crystalline region of which crystallization occurred from the second projection,   removing at least a portion of the first semiconductor film between the first channel region and the second channel region.