| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a matrix type large capacity memory device employing a resistance change memory cell. <P>SOLUTION: A memory element 100 has an intermediate electrode layer 102, a metal oxide layer 103 and an upper electrode 104 on a semiconductor substrate 101 wherein an ohmic contact 105 is provided at a part of the semiconductor substrate 101. The metal oxide layer 103 is composed of bismuth (Bi), titanium (Ti) and oxygen, and formed to have a film thickness of 30-200 nm or formed on the intermediate electrode layer 102 in contact therewith. For example, the metal oxide layer 103 is composed of a base layer containing excessive Ti as compared with the stoichiometric composition of Bi<SB>4</SB>Ti<SB>3</SB>O<SB>12</SB>, and a plurality of microcrystal grains which are about 3-15 nm of the stoichiometric composition of Bi<SB>4</SB>Ti<SB>3</SB>O<SB>12</SB>diffused in the base layer. Since the memory cell M has rectification characteristics, sneak current to a nonselect memory cell can be suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT |
