Disclosed are a fast, highly-integrated and highly-reliable magnetoresistive
random access memory (MRAM) and a semiconductor device which uses the MRAM. The
semiconductor device performs the read-out operation of the MRAM using memory cells
for storing information by using a change in magnetoresistance of a magnetic tunnel
junction (MTJ) element with a high S/N ratio. Each memory cell includes an MTJ
element and a bipolar transistor. The read-out operation is carried out by selecting
a word line, amplifying a current flowing in the MTJ element of a target memory
cell by the bipolar transistor and outputting the amplified current to an associated
read data line.
