Field Effect Transistor Sensitive to Dipolar Molecules.

A field effect transistor with metal gate suspended above the gate insulator has been fabricated. Fluid samples can freely penetrate into the gap formed between the metal and the insulator. If the molecules carry an electrical dipole, they will alter the surface potential on these two materials giving rise to a change in the drain current of the transistor. Our preliminary results confirm this mechanism for dipolar molecules such as methanol and methylene chloride. Author