Method for measuring resistivity of semiconductor wafer
US6914442B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 2003 |
| Grant date | Jul 5, 2005 |
| Priority date | — |
| Expiry date | Jan 6, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2648
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention is to provide a method for measuring resistivity of a semiconductor wafer by the use of an AC-SPV method even though the wafer is left in a depletion state or a weak inversion state. The present invention is the method for measuring resistivity of a semiconductor wafer by the use of a surface photo voltage method, and comprises the steps of: (a) measuring a surface photo voltage value in both regions of a low frequency region in which a constant surface photo voltage value is obtained irrespective of a frequency of incident light on a semiconductor wafer to be measured and in a high frequency region in which the surface photo voltage value inversely proportional to the frequency of the incident light is obtained and calculating a cut-off frequency fc from the obtained measured value; (b) calculating a depletion layer width Wd from capacitance Cdp calculated from the surface photo voltage value in the high frequency region; (c) calculating majority carrier conductance gmj from the cut-off frequency fc and the capacitance Cdp; and (d) calculating surface potential Us and Fermi potential UF from the cut-off frequency fc, the capacitance Cdp, the depletion layer w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.