Phase change memory cell with heater and method therefor
View Patent ↗A method for forming a phase change memory cell (PCM) includes forming a heater for the phase change memory and forming a phase change structure electrically coupled to the heater. The forming a heater includes siliciding a material including silicon to form a silicide structure, wherein the heater includes at least a portion of the silicide structure. The phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state. The silicide structure produces heat when current flows through the silicide structure for changing the phase state of the phase change structure.
1. A method of forming a circuit including a phase change memory cell, the method comprising:
forming a heater for the phase change memory cell, wherein the forming a heater includes forming a silicon region having a first portion joined to a second portion with a narrowed portion narrower than the first portion and the second portion, etching back the silicon region to separate the first portion from the second portion and to result in the first portion coming to a first point and the second region coming to a second point, siliciding the first point to form a silicided first point and siliciding the second point to form a silicided second point separated from the silicided first point, wherein the heater includes the silicided first point and the silicided second point;
forming a phase change structure electrically coupled to the heater and in contact with the silicided first point and the silicided second point, wherein the phase change structure exhibits a first resistive value when in a first phase state and exhibits a second resistive value when in a second phase state;
wherein the silicide structure produces heat at the silicided first point and the silicided second point when current flows between the first point and the second point for changing a phase state of the phase change structure.
2. The method of claim 1 wherein the thinning includes oxidizing portions of the patterned structure and removing at least portions of the oxidized portions to expose unoxidized portions of the patterned structure, wherein the siliciding includes forming silicide from the unoxidized portions.
3. The method of claim 1 wherein the siliciding includes depositing cobalt.
4. The method of claim 1 wherein the siliciding includes depositing at least one of a group consisting of tantalum and tungsten.