  Sensing technologies have been under research and development for their
varied applications from microelectronics to space exploration. With the end of
Moores law in sight, there is growing demand for shrinking materials and
improving sensitivity and range of sensing of sensors. Carbon nanotubes (CNTs)
offer an excellent combination of small size (in the order of nanometers in two
dimensions and micrometers in the third dimension), varied current conductivity
(from insulating to metallic), flexibility, mechanical strength and feasibility
of mass production. Here we used CNTs to fabricate pressure sensors to sense
static loads of pressure and studied the characteristics of different methods
of building the sensors. We offer an adhesive-absorption technique of
fabrication of pressure sensors that tackles the issue of endurance of the
sensors to repeated operation. We demonstrate a significant change in
resistance of a vertically aligned forest of nanotubes upon application of
static loads. This study will enable building of better pressure sensors for
several applications.
