Fig. 7. Electrical output and transfer curves of theWSe₂ and MoSe₂ devices. (a and b) I_d–V_g of the WSe₂ FET at fixed V_gs = 1 V; I_ds–V_ds of the WSe₂ FET at V_ds: 20 V to −40 V (inset). (c and d) I_ds–V_gs of the MoSe₂ FET at V_gs = 1 V; I_ds–V_ds of the MoSe₂ FET at V_ds: 20 V to −40 V (inset).