Measuring a property of a layer in multilayered structure
US6906801B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 2003 |
| Grant date | Jun 14, 2005 |
| Priority date | — |
| Expiry date | Nov 25, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus measures a property of a layer (such as the sheet resistance of a conductive layer or thermal conductivity of a dielectric layer that is located underneath the conductive layer) by performing the following method: (1) focusing the heating beam on the heated a region (also called “heated region”) of the conductive layer (2) modulating the power of the heating beam at a predetermined frequency that is selected to be sufficiently low to ensure that at least a majority (preferably all) of the generated heat transfers out of the heated region by diffusion, and (3) measuring the power of another beam that is (a) reflected by the heated region, and (b) modulated in phase with modulation of the heating beam. The measurement in act (3) can be used directly as a measure of the resistance (per unit length) of a conductive line formed by patterning the conductive layer. Acts (1)-(3) can be repeated during fabrication of a semiconductor wafer, at each of a number of regions on a conductive line, and any change in measurement indicates a corresponding change in resistance of the line. When the measurement changes by more than a predetermined amount (e.g. by 10%), a process parameter…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.