Patent ID: 11906451
Assignee: NOVA LTD.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A method for determining at least one property of an integrated circuit (IC) comprising a structure, the method comprises:
illuminating the structure with an x-ray beam, during an execution of a measurement selected out an x-ray photoelectron spectroscopy (XPS) measurement and an x-ray fluorescence spectroscopy (XRF) measurement; wherein the structure comprises a layer on top of an underlayer; wherein the layer has an uneven topography and comprises a layer top surface, layer sidewalls that are not parallel to the layer top surface, and a layer bottom surface; wherein the underlayer has an uneven topography and comprises an underlayer top surface, underlayer layer sidewalls that are not parallel to the underlayer top surface and an underlayer bottom surface;
detecting layer emitted photoelectrons and underlayer emitted photoelectrons; wherein the detected layer emitted photoelectrons comprise photoelectrons emitted from the layer top surface and photoelectrons emitted from the layer sidewalls; wherein the detected underlayer emitted photoelectrons comprise photoelectrons emitted from the underlayer top surface and photoelectrons emitted from the underlayer sidewalls;
determining a layer intensity function for the layer emitted photoelectrons, wherein the layer intensity function is responsive to photoelectrons emitted from the layer top surface, to photoelectrons emitted from the layer sidewalls, to photoelectrons emitted from the layer bottom surface and to layer coefficients that accommodate for the uneven topography of the layer; wherein the determining of the layer intensity function is based, at least in part, on one or more optical critical dimension (OCD) measurement obtained dimensions of the structure;
determining an underlayer intensity function for the underlayer emitted photoelectrons, wherein the underlayer intensity function is responsive to photoelectrons emitted from the underlayer top surface, to photoelectrons emitted from the underlayer sidewalls, to photoelectrons emitted from the underlayer bottom surface, and to underlayer coefficients that accommodate for the uneven topography of the underlayer;
calculating a ratio between the layer intensity function and the underlayer intensity function; and
determining a thickness of the layer based on the ratio.