A themal micro-sensor made of polysilicon is illustrated in Figure below. It consists of a circular plate suspended by four beams. The beams have a length of L= 120 um, and a cross-section of w= 8 um by t = 4 um. An electric-heater element and two metal leads is deposited using a layer of Aluminum as shown in the Figure. Assume that the aluminum leads have a cross-section of wm = 6um and tm = 1 um. Let the electric resistance of the central heater be 1500 ohms. (a) If a voltage of 5 VDC is applied between point a and b, what is the temperature difference between the circular plate and the surrounding substrate? Assume that the surrounding substrate is at room temperature. Ignore the effects of convection and radiation. (b) (b) As part of your answer, draw the equivalent thermal eircuit' to model the heat flow in this system. Beam Cro-Section:

A themal micro-sensor made of polysilicon is illustrated in Figure below. It consists of a circular plate suspended by four beams. The beams have a length of L= 120 um, and a cross-section of w= 8 um by t = 4 um. An electric-heater element and two metal leads is deposited using a layer of Aluminum as shown in the Figure. Assume that the aluminum leads have a cross-section of wm = 6um and tm = 1 um. Let the electric resistance of the central heater be 1500 ohms. (a) If a voltage of 5 VDC is applied between point a and b, what is the temperature difference between the circular plate and the surrounding substrate? Assume that the surrounding substrate is at room temperature. Ignore the effects of convection and radiation. (b) (b) As part of your answer, draw the equivalent thermal eircuit' to model the heat flow in this system. Beam Cro-Section:

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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