Method for manufacturing three-dimensional semiconductor device by sequential beam epitaxy

A method for manufacturing a three-dimensional semiconductor device comprising the steps of:

• forming first and second semiconductor elements on the surface of a single-crystalline semiconductor substrate;
• forming a first insulating film on said substrate;
• forming a first opening in said first insulating film at a predetermined portion of said first semiconductor element;
• forming a first polycrystalline or amorphous semiconductor layer on said first insulating film having said first opening;
• irradiating said first semiconductor layer with an energy beam to grow a single crystal in a predetermined region in said first semiconductor layer using as a seed crystal that part of said semiconductor substrate which contacts said first semiconductor layer and to form a first single-crystalline semiconductor region;
• forming at least a part of a third semiconductor element in said first single-crystalline semiconductor region;
• forming an interconnection between said first and third semiconductor elements by using a part of said first single-crystalline semiconductor region from said semiconductor substrate to said third element;
• forming a second insulating film having a second opening at a predetermined portion of said second semiconductor element so as to elongate on said first single-crystalline semiconductor region;
• forming a second polycrystalline or amorphous semiconductor layer on said second insulating film having said second opening;
• irradiating said second semiconductor layer with an energy beam to grow a single crystal at a predetermined region in said second semiconductor layer using as a seed crystal that part of said semiconductor substrate which contacts with the second semiconductor layer and to form a second single-crystalline semiconductor region;
• and
• forming a remaining part of said third semiconductor element and forming an interconnection between said second and third semiconductor elements by using a part of said second single-crystalline semiconductor region from said semiconductor substrate to said third semiconductor element.