System for characterizing semiconductor materials and photovoltaic devices through calibration
US5757474A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1995 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Jun 28, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/9501
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.