| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide inspection method and structure for increasing the reliability of a memory cell including a transistor with extremely high off resistance as a switching element. <P>SOLUTION: A memory cell that does not have a sufficient data storage characteristic is eliminated by determining whether the threshold value V<SB POS="POST">th</SB>of a transistor of a memory cell is in the allowable range. For this reason, the potential of a gate of the transistor is held at an appropriate potential V<SB POS="POST">GM</SB>and the potential of a drain of the transistor is set to be V<SB POS="POST">GM</SB>or more. By writing in the memory cell in this state, the potential of a source of the transistor is expressed with the formula including the threshold value V<SB POS="POST">th</SB>(V<SB POS="POST">GM</SB>-V<SB POS="POST">th</SB>). By comparing this potential with another reference potential, whether the threshold value V<SB POS="POST">th</SB>is in the allowable range or not can be determined. <P>COPYRIGHT: (C)2012,JPO&INPIT |
