A Monolithic CMOS Microhotplate-Based Gas Sensor

SystemMuhammad Y. Afridi

John S. Suehle

Mona E. Zaghloul

David W. Berning

Allen R. Hefner

Elliott Cooper-Balis

MEMS Overview

The integration of mechanical elements, sensors, actuators, and electronics on a common silicon substrate through micro-fabrication technology

Gas Sensor Motivations

• Use existing CMOS technology

• Low power

• Low cost

• Reliable detection

• Applications :

• Detection of harmful substances in public places

• Detection of freshness of food

• Detection of toxic leaks in manufacturing facilities

Microhotplate Gas Sensor

Key Features :

• Suspended trampoline structure

• Polysilicon resistor heating element (2-kΩ)

• Metal-oxide film-based sensing element (Tin or Titanium)

Microhotplate Gas Sensor

Gas Sensor System

Gas Sensor System

Gas Sensor System

Gas Sensor System

Gas Sensor System

Thank You!