Analytical derivation of charge relaxation time distribution in transistor from current noise spectrum using inverse integral transformation method

An analytical technique is proposed to reveal the relaxation time distribution of dynamic charge events using the current noise spectrum of a transistor, by applying an inverse integral transformation to the McWhorter model. In the proposed method, the continuous relaxation-time distribution function G(τ) can be analytically derived from the noise spectra S(ω) without a spectrum deconvolution. The feasibility of the proposed method is demonstrated by characterizing the charge dynamics of tetraphenylporphyrin molecules dispersed on the surface of a GaAs-based nanowire field-effect transistor. Our analysis successfully verified the time constant of the molecule-related dynamic charge events and effects of photo-excitation.