Feb 11 2011
A team of researchers working at Harvard University have fabricated an MEMS force sensor from paper, making it cost- effective and almost disposable.
Harvard University's Paper accelerometer
The device is based on the piezo resistive silicon MEMS sensor that displays resistivity changes in a material when it is subjected to pressure.
According to George Whitesides, who is a chemistry professor at the university, does not expect paper sensors to replace silicon accelerometers and the device could be used in consumer and medical applications. The device can be made using a paper cutter or painting knife
The device is a cantilever taken from thick chromatography paper used to conduct chemistry experiments. A bit of carbon and silver contact pads at the bottom of the cantilever are screen printed with graphite and silver inks. They also use stencils made from vinyl film. When pressure is applied to the cantilever it bends, the carbon resistance alters. The team constructed an electrical circuit to measure the carbon stress by sticking together resistors at specific spots and integrated them into the circuit with silver ink.