The present research letter is dedicated to a detailed analysis of a double-gate tunnel field-effect transistor (DG-TFET). The DG-TFET provides improved on-current (I ON) than a conventional TFET via bandto-band (B2B) tunneling. However, DG-TFET is disadvantageous for low-power applications because of increased off-current (I OFF) due to the large ambipolar current (I amb). In this research work, a Si/GaAs/ GaAs heterostructure DG-TFET is considered as research base for investigation of device performance. The electrical parameters of the DG-TFET device have been improved in comparison to the homostructure. The transfer (I-V) characteristics, capacitance-voltage (C-V) characteristic of homo structure Si/ Si/Si and hetero structure Si/GaAs/GaAs, DG-TFET both structures is analysed comparatively. The C-V characteristics of DG-TFET have obtained using operating frequency of 1 MHz. The ambipolar current Iamb is suppressed by 5 × 10 8 order of magnitude in proposed Si/GaAs/GaAs hetero DG-TFET as compared to Si/Si/Si homo DG-TFET up to the applied drain voltage very low equal to VDS = 0.5 V without affecting on-state performance. The simulation result shows a very good I ON /I OFF ratio (10 13) and low subthreshold slope, SS (~36.52 mV/dec). The various electrical characteristics of homo and hetero DG-TFET such as on-current (I ON), off-current (I OFF), time delay (ι d), transconductance (g m) , and power delay product (PDP) have been improve in Si/GaAs/GaAs heterostructure DG-TFET and compared with Si/Si/ Si homo DG-TFET. The advantageous results obtained for the proposed design show its usability in the field of digital and analog applications.