Développement d'un dispositif intégré de photodétection de grande sensibilité avec discrimination spectrale pour les laboratoires sur puce

This thesis aims to develop an integrated photosensor device for biomedical applications requiring high detection sensitivity and spectral discrimination (selectivity). For example, this system can be applied to mesure simultaneous emissions of several fluorescent labels in lab-on-a-chip implementing very small volumes of reagents (less than one microliter). The thesis focuses on the design, implementation and testing of this integrated photodetector device. The work is divided in two main parts: first, the design of a CMOS photodetector with integrated preamplifiers, and secondly the design, realization and characterization of integrated optical filters for fluorescence detection. The detection device implements a Buried Quad Junction photodetector (BQJ) and charge sensitive preamplifiers for the simultaneous treatment of its four outputs. The chip was made in 0.8μm High Voltage CMOS technology from Teledyne-DALSA. Its operation has been demonstrated and its performances, especially in terms of noise and sensitivity, have been characterized. In parallel, optical notch filters have been developed using a process compatible with the CMOS technology used for the photodetector fabrication. Thus, deposition of these filters on the photodetector can be integrated during industrial process. Developed interference filters are made by alternating deposition of thin layers of nitride and silicon oxide by PECVD. Measurements of refractive index of these materials were used to optimize these filters through simulations. The filters implemented on a glass cover or on the BQJ photodetector were characterized. Signal processing methods specific to BQJ are also proposed to improve the detection’s sensitivity and/or selectivity. Their performances were evaluated. Finally, fluorescence measurements with the designed photodetection device were performed on mixtures of fluorescent nanocrystals (quantum dots) or of organic fluorophores. These preliminary results validate the performances in terms of photodetection of the designed integrated photodetection device.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

Doctorat

Discipline thesis:degree_discipline

Génie électrique

Grantor dc:publisher

Université de Sherbrooke

Year dc:date.issued

2014

Author dc:creator

• Courcier, Thierry

Advisors dc:contributor.advisor

• Aimez, Vincent
• Charette, Paul G.
• Lu, Guo - Neng

• Laboratoire sur puce
• Photodétecteur à quatre jonctions enterrées
• Fluorescence
• Filtre interférentiel
• Filtre absorbant
• Préamplification de charge
• Lab-on-a-chip
• Buried quad junction photodetector
• Interference filter
• Absorbing filter
• Charge preamplifier

Language dc:language.iso

fr

Handle dc:identifier.uri

http://hdl.handle.net/11143/5392

OAI identifier oai:identifier

oai:usherbrooke.scholaris.ca:11143/5392