Designing method of non-volatile memory device, manufacturing method of non-volatile memory device, and non-volatile memory device

摘要

A method of designing a cross-point non-volatile memory device including memory elements arranged in (N×M) matrix, each of the memory elements including a variable resistance element and a bidirectional current steering element connected in series with the variable resistance element, the method comprises the step of: when an absolute value of a low-resistance state writing voltage is VR and an absolute value of a current flowing through the variable resistance element having changed to a low-resistance state by application of the low-resistance state writing voltage to both ends of the variable resistance element in a high-resistance state is Ion, and a relationship between a voltage V0 applied to both ends of the bidirectional current steering element and a current I flowing through the bidirectional current steering element is approximated as |V0|=a×Log(I)+b, deciding N, M, VR, Ion, a, and b such that b−VR/2>a×[Log {(N−1)×(M−1)}−Log(Ion)] is satisfied (S101).

主权项

1. A method of designing a cross-point non-volatile memory device including memory elements arranged in (N ×M) matrix, each of the memory elements including a variable resistance element and a bidirectional current steering element connected in series with the variable resistance element,
the variable resistance element being configured such that when a high-resistance state writing voltage is applied to the variable resistance element in a low-resistance state, the variable resistance element reversibly changes to a high resistance state in which the variable resistance element has a greater resistance value than in the low-resistance state, while when a low-resistance state writing voltage different in polarity from the high-resistance state writing voltage is applied to the variable resistance element in the high-resistance state, the variable resistance element reversibly changes to the low-resistance state, the method comprising the step of: when an absolute value of the low-resistance state writing voltage is VR and an absolute value of a current flowing through the variable resistance element having changed to the low-resistance state by application of the low-resistance state writing voltage to both ends of the variable resistance element in the high-resistance state is Ion, and a relationship between a voltage V0 applied to both ends of the bidirectional current steering element and a current I flowing through the bidirectional current steering element is approximated as|V0 |=a ×Log (I) +b, deciding N, M, VR, Ion, a, and b such that b −VR /2 >a ×[Log {(N −1) ×(M −1)}−Log (Ion)] is satisfied.