1.1µm Backside Imager vs. Frontside Imager: an optics-dedicated FDTD approach
Résumé
In 2009 the race to miniaturization and high performance of CMOS image sensors lead companies to propose 1.4µm pixels and to develop 1.1µm pixels with high signal to noise ratio even at low light level. At this scale diffraction effects of metallic interconnections of Frontside (FSI) technology become preponderant and can limit the quantum efficiency while degrading crosstalk. A promising technology to overcome these effects is the Backside (BSI) technology: the light passes through the back thinned side of the sensor and is not disturbed by the metallic windows. In this paper we propose to evaluate the optical performances of a 1.1µm BSI pixel compared to a 1.1µm FSI pixel using a Finite Difference Time Domain simulation we previously developed at STMicroelectronics. After a calibration of the BSI modeling on a realized and measured 1.4µm pixel, we will compare the spots sizes, the transmitted energies at silicon interface and the energy distribution inside the silicon of the BSI and FSI 1.1µm pixels.
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|---|
| Licence |