Phase change material switch and method of making the same

A method for making a phase change material (PCM) switch, the method comprising:

• forming an insulating layer over a substrate;
• forming a resistive heater element over the insulating layer;
• depositing a thermally conductive electrical insulating barrier layer over the resistive heating element;
• forming openings in the barrier layer aligned with ends of the resistive heater element;
• forming a patterned photoresist over the barrier layer with an opening overlying and aligned with the resistive heater device;
• sputtering PCM in its amorphous state to form a PCM element;
• removing the patterned photoresist and excess PCM by applying a chemical solvent lift-off material;
• performing an anneal process to change the PCM element from its amorphous state to its crystalline state to enhance its immunity to deleterious effects caused by further processing;
• and
• forming conductive lines from ends of the PCM element and control lines from ends of the resistive heater element.

A method of making a phase change material (PCM) switch, the method comprising:

• forming a resistive heater element;
• forming a PCM element proximate the resistive heater element;
• forming a thermally conductive electrical insulating barrier layer positioned between the PCM element and the resistive heating element;
• and
• forming conductive lines extending from ends of the PCM element and control lines extending from ends of the resistive heater element comprising:
• forming a patterned photoresist over the barrier layer and the PCM element with trenches extending from both ends of the PCM and trenches extending from both openings in the barrier layer aligned with ends of the resistive heater element;
• depositing a conductive material to form conductive lines extending from each end of the PCM element and control lines extending from each end of the resistive heater element;
• and
• removing the patterned photoresist and excess conductive material by applying a chemical solvent lift-off material.