A phase change memory includes a sidewall insulation film and a heater
electrode which are formed in a contact hole formed in an interlayer
insulation film on a lower electrode. The heater electrode has a recessed
structure. In a recessed area surrounded by the sidewall insulation film,
the heater electrode and a phase change film are contacted with each
other. A phase change region is formed only in an area contacted with the
sidewall insulation film. The sidewall insulation film is an
anti-oxidizing insulation film. The phase change region and the heater
electrode which are heated to a high temperature upon rewriting are not
contacted with the interlayer insulation film as an oxidizing insulation
film.