Non-volatile semiconductor memory device with thin film transistor formed on a separation insulating film adjacent to a memory cell, and method of making thereof

A non-volatile semiconductor memory device, comprising:

• a semiconductor substrate having a surface with a principal plane;
• a plurality of memory cells formed on said principal plane of said semiconductor substrate surface;
• an element separation insulating film selectively formed on said surface of said semiconductor substrate adjacent to areas of said semiconductor substrate on which said memory cells are formed;
• and
• a plurality of thin film transistors formed on said element separation insulating film adjacent to said memory cells, wherein a predetermined number of said memory cells is connected to a first bit line in parallel, and the first bit line is connected to one of source and drain regions of each of said thin film transistors and the other of said source and drain regions is connected to a second bit line.

A non-volatile semiconductor memory device, comprising:

• a semiconductor substrate having a surface with a principal plane;
• a plurality of memory cells formed on said principal plane of said semiconductor substrate surface;
• an element separation insulating film selectively formed on said surface of said semiconductor substrate adjacent to areas of said semiconductor substrate on which said memory cells are formed;
• and
• a plurality of thin film transistors formed on said element separation insulating film adjacent to said memory cells, wherein said thin film transistors are selection transistors for selectively reading out data stored in said memory cells.

A non-volatile semiconductor memory device, comprising:

• a semiconductor substrate having a surface with a principal plane;
• a plurality of memory cells formed on said principal plane of said semiconductor substrate surface;
• an element separation insulating film selectively formed on said surface of said semiconductor substrate adjacent to areas of said semiconductor substrate on which said memory cells are formed;
• and
• a plurality of thin film transistors formed on said element separation insulating film adjacent to said memory cells, wherein said thin film transistors are sector erasing transistors for selectively erasing data stored in said memory cells.

A method of making a non-volatile semiconductor memory device, comprising the steps of:

• providing a semiconductor substrate having a surface with a principal plane;
• forming a plurality of memory cells on said principal plane of said semiconductor substrate surface;
• forming an element separation insulating film selectively on said surface of said semiconductor substrate adjacent to areas of said semiconductor substrate on which said memory cells are formed;
• forming a plurality of thin film transistors on said element separation insulating film adjacent to said memory cells;
• forming a first insulating film over and between each of said plurality of thin film transistors so that said plurality of thin film transistors are selectively separated and insulated from one another;
• and
• connecting one of the source and drain regions of at least one of said thin film transistors and a diffusion layer of at least one of said memory cells to each other, and to a bit line, through a common contact hole.