title: Charge-trapping effects caused by ammonia in carbon nanotubes.
abstract: Hysteretic behaviors caused by low-concentration ammonia gas are found in single-walled carbon nanotube based field-effect transistors. The transfer curves are found to shift towards negative gate voltage when the gate voltage is swept forwardly upon introducing ammonia. In contrast, no significant change in the transfer curves is observed for the backward sweeping of the gate voltage. This phenomenon is repeatable even after the devices are annealed in dry air at 200 degrees C for 2 hrs. Our findings can be interpreted in terms of additional charge traps induced by the adsorbed ammonia molecules. The observed hysteretic behavior enables the devices to work as memory cells, in which the carbon nanotube field-effect transistors act as readout and ammonia molecules play roles of charge storage.
authors: Microelectronics Center, School of Electrical and Electronic Engineering, Nanyang Technological University, S1-B2c-20, Singapore 639798.
authors: Hong
authors: H
authors: Li
authors: Qing
authors: Q
authors: Zhang
authors: Ning
authors: N
authors: Peng
authors: Ningyi
authors: N
authors: Liu
authors: Yi Chau
authors: YC
authors: Lee
authors: Ooi Kiang
authors: OK
authors: Tan
authors: Nicola
authors: N
authors: Marazari
authors: Carl V
authors: CV
authors: Thompson
mesh_terms: D000327:Adsorption; D000641:Ammonia / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D004583:Electrons; D008956:Models, Chemical; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D037742:Nanotubes, Carbon; D014867:Water; D002244:Carbon; D000641:Ammonia