Electrostatic discharge path for preventing plasma-induced damage during patterning of phase change material and method for forming the same

A method of forming a device structure, comprising:

• providing a stack comprising a semiconductor substrate embedding a doped semiconductor region, dielectric material layers having formed therein metal interconnect structures, and an insulating layer;
• etching a via opening through at least the insulating layer;
• depositing a metal layer overlying the insulating layer and in the via opening;
• forming a heater element of a phase change memory (PCM) switch and an electrostatic discharge metal structure, wherein the electrostatic discharge metal structure comprises a patterned portion of the metal layer that fills the via opening;
• depositing a phase change material layer over the heater element and the electrostatic discharge metal structure;
• and
• performing an anisotropic etch process that etches an unmasked portion of the phase change material layer, wherein an electrostatic discharge path comprising the electrostatic discharge metal structure and the doped semiconductor region discharges electrostatic charges that accumulate in the insulating layer into the semiconductor substrate.

A device structure comprising:

• semiconductor devices located on a semiconductor substrate;
• a doped semiconductor region located in an upper portion of the semiconductor substrate;
• dielectric material layers located over the semiconductor devices and metal interconnect structures formed therein;
• an insulating layer overing the dielectric material layers;
• a phase change memory (PCM) switch located over the insulating layer, wherein the phase change memory switch comprises a heater element comprising a second portion of a set of at least one metallic material;
• and
• an electrostatic discharge path comprising the doped semiconductor region and an electrostatic discharge metal structure which vertically extends through the insulating layer, comprises a first portion of the set of at least one metallic material, and is electrically connected to the doped semiconductor region.