Interferometer Type Pressure Microsensor
- PDF / 313,210 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 20 Downloads / 189 Views
0888-V03-18.1
Interferometer Type Pressure Microsensor A. Heredia-J1, A. Ramírez-P1, J. Sánchez Mondragón 2, A. Andrade Lucio3, M. Basurto Pensado 4, R. J. Romero 4, A. Torres-J2. 1 Universidad Popular Autónoma del Estado de Puebla, Puebla, México, 2 INAOE, Puebla, México, 3 UG, Guanajuato, México, 4 UAEM, Cuernavaca, México. [email protected]
Abstract In this work, the fabrication of waveguide and nitride silicon membrane is presented. The measurement configuration chosen to detect the variation produced in the light properties is an Interferometer configuration of the Mach Zehnder Type (MZI), because of its high sensitivity. One of its arms is positioned on a floating silicon nitride membrane that becomes deformed under small pressures on the range of MPa. According to the parameters of the membrane and the waveguide we obtain a maximum deformation of 176 nm that produces a change of phase of 180o between the two waves, producing therein a null interferometer output for the maximum pressure. The analyses of theory suggest that this device will be able to sense a pressure value up to13.376MPa. I Introduction Currently, the sensors based on integrated optics devices have a great importance due to their high sensibility, mechanical stability, possibility of miniaturization and integration in microsystems and production to great scale. Also, the combination of the integrated optics devices and MEMS technologies can lead to obtain devices with high sensitivity and efficiency. Then, in this work, the fabrication and some theory behavior of an interferometer pressure microsensor based on silicon are presented. In section 2 the proposed arrangement and interferometer description are given. Section 3 presents the fabrication process. The discussion of the results is presented in section 4. Finally in section 5 the conclusions of this work are presented. II The proposed arrangement and interferometer description The figure 1 shows the block diagram of the proposed arrangement and indicates the appropriate components. The first component is a laser light source; this provides the carrier of information. The second block is the focus system that concentrates light to input of the waveguide. The third is the light modulator (main component) which is a device that permits detection of membrane bending by the pressure application and is able of transmition through the optical fiber (fourth component). The fifth component is a photodiode, and finally the analyzer for information visualization.
Light source
Focus Optics
Modulator
Optical fiber
Photodiode
analyzer
Fig.1. block diagram of the proposed the arrangement. The main component of the arrangement is the electro-optic modulator, which is formed by a Mach Zehnder interferometer. This modulator works in the following way: Light intensity modulation at the output end is obtained by interference from a phase modulated guided mode and a reference guided mode. A waveguide interferometer is easily constituted by a combining two Y-junction waveguides, as shown in Figu
Data Loading...
