Full text
| |
| Author(s): |
Douglas Anderson Pereira Bulla
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 1999-07-07 |
| Examining board members: |
Nilton Itiro Morimoto;
Ben Hur Viana Borges;
Murilo Araujo Romero;
Josemir Coelho Santos;
Patrick Bernard Verdonck
|
| Advisor: | Nilton Itiro Morimoto; Luiz Goncalves Neto |
| Abstract | |
The planar technology is widely used in integrated circuits fabrication. This technology is being used to build optical sensors which can be integrated with electronic circuits in a same package. Silicon oxide and silicon nitride thin films have suitable optics proprieties for these devices and they are compatible with usual microelectronics processes. In this work, optical waveguides were fabricated, on silicon wafers, using silicon oxide and silicon nitride layers. The silicon oxide layers were obtained by thermal oxidation of the silicon wafer or deposited by PECVD (Plasma Enhanced Chemical Vapor Deposition). A LPCVD (Low Pressure Chemical Vapor Deposition) process was used to deposit the silicon nitride layers. The processes were optimized to obtain thin films with suitable optical quality for sensors application. The resulting optical waveguides showed monomode and multimode propagation. The optical losses (by optical propagation and fiber coupling) were measured and the results are comparable to those mentioned in the literature. Diaphragms were fabricated to show the feasibility of the process to implement pressure optical sensors using a Mach-Zender interferometer. The experimental results were used for mechanical and optical simulation of the pressure and evanescent sensors proposed in this work. (AU) | |