Memory device having a transistor and one resistant element as a storing means and method for driving the memory device

A method for writing bit data of a memory device that includes a semiconductor substrate;

• an NPN-type transistor formed on the semiconductor substrate;
• an interlayer insulating film formed on the semiconductor substrate to cover the transistor, in which a contact hole exposing the source region of the transistor is formed;
• a conductive plug filling the contact hole;
• a resistant material in which a bit data “0” or “1” is written formed on the conductive plug;
• and a conductive plate formed on the interlayer insulating film to be contacted with the resistant material, the method comprising:
• initializing the resistant material;
• and
• enhancing the resistance of the resistant material and writing the bit data “0” or “1” therein.

A method for reading a written bit data in a memory device that includes a semiconductor substrate;

• an NPN-type transistor formed on the semiconductor substrate;
• an interlayer insulating film formed on the semiconductor substrate to cover the transistor, in which a contact hole exposing a source region of the transistor is formed;
• a conductive plug filling the contact hole;
• a resistant material in which a bit data “0” or “1” is written formed on the conductive plug;
• and a conductive plate formed on the interlayer insulating film to be contacted with the resistant material, wherein the bit data which is written in the resistant material is read by measuring a current flowing through the resistant material and reading the written bit data in the resistant material.