“…After excluding the other current transport mechanisms such as the Pool−Frenkel emission, Schottky emission, thermionic emissions, etc., an Ohmic emission and spacecharge-limited current (SCLC) are concluded, respectively. 28,29 The R 2 values for the low-voltage and high-voltage regions at applied biases of 5, 7, and 9 V are greater than 0.99, which confirmed the valid fitting results with the coefficient of determination. The space-charge-limited current of three bias conditions are shown in the I−V characteristics, which shows that there is no bias dependence on current transport models in the helical selection devices.…”