ANALYZING THE MECHANISM OF HYDROGEN ADSORPTION EFFECTS ON DIAMOND BASED MIS HYDROGEN SENSORS

The current conduction mechanism and the change in device parameters o f diamond based MIS hydrogen sensor upon hydrogen adsorption is invest igated over the temperature range of 27-100 degrees C. The current con duction mechanism of the diamond based hydrogen sensitive MIS diode in the forward-bias region is found to be space charge limited in air an d hydrogen environments. The space charge limited current (SCLC) condu ction mechanism is characterized by an ohmic region at low bias voltag e and a power law dependency of voltage (I similar to V-n with n great er than or equal to 2) at higher voltage range. The space charge limit ed current (SCLC) conduction mechanism prohibits the use of convention al methods to determine the device parameters. This paper presents a m ethod to determine device parameters such as the ideality factor, n, b arrier height, phi(B), and tunneling factor, a chi(1/2)delta, and expl ain the change in these parameters upon H-2 adsorption.