Phase change memories and fabrication method

The method according to claim 7, wherein:

• the phase change layer is made of GeiSbjTekor nitrogen, oxygen or carbon doped GeiSbjTek;
• wherein:
• j and k real are numbers referring to atomic percentages;
• 0≦i<1;
• 0≦j<1;
• 0≦k<1;
• and
• i+j+k=1.

A phase change memory, comprising:

• a semiconductor substrate having a bottom electrode inside connecting with one or more of semiconductor devices;
• a first dielectric layer consisting a portion of a fifth dielectric layer and a portion of the sixth dielectric layer on the semiconductor substrate;
• a loop-shape electrode in the first dielectric layer;
• a second dielectric layer on the first dielectric layer and the loop-shape electrode;
• a phase change layer in the second dielectric layer such that a contact area between the phase change layer and the loop-shape electrode may be controlled to achieve desired contact;
• and
• a top electrode electrically connecting with the phase change layer.
• wherein:
• the loop shape electrode is formed by sequentially:
• forming the fifth dielectric layer on the semiconductor substrate;
• forming a third opening in the fifth dielectric layer;
• forming a loop-shape electrode material layer in the third opening covering bottom and sidewall of the third opening;
• forming the sixth dielectric layer on the loop-shape electrode material layer such that a contact area between the phase change layer and the loop-shape electrode may be controlled to achieve desired contact;
• and polishing the sixth dielectric layer and the loop-shape electrode material layer until the fifth dielectric layer is exposed.