Method and apparatus for detection of chemical mechanical planarization endpoint and device planarity

A method for measuring metrological requirements of the chemical mechanical polishing of a semiconductor device, using a polishing tool supported within a tool chamber whereby the polishing produces a gaseous effluent during said polishing, and said method comprising the steps of:

• (a) introducing a first spiking material into a device layer of a semiconductor device, at a predetermined depth of the device layer, and said spiking material dispersed within a predetermined thickness of the device layer;
• (b) introducing a second spiking material to the device layer at a predetermined thickness above the first spiking material, the second spiking material having an atomic mass different from an atomic mass of the first spiking material;
• (c) introducing trace samples of the gaseous effluent into a measuring system in fluid communication with the tool chamber, during the polishing of the semiconductor device;
• and,
• (d) measuring an abundance of the first spiking material and the second spiking material over a predetermined time duration in an effluent produced during polishing of the semiconductor device.

A method of fabricating a structure, comprising the steps of:

• (a) providing at least one material within a layer formed on a substrate, and said at least one material having at least two isotopic variations in atomic mass, wherein a change in the atomic mass with respect to said at least one material is a function of layer thickness;
• (b) removing at least a portion of the layer from the substrate;
• (c) detecting the presence of each of the at least two variations of atomic mass of said at least one material during removal of the layer;
• and
• (d) terminating the removal of the layer at a predetermined threshold of concentration of the isotopic variations indicative of an endpoint of the removal of said portion of the layer.