Because of its improved recognition and learning abilities in computing of neural network, three-terminal neuromorphic transistors have received a lot of attention. High-Synaptic weight (G) (i.e., conductance) and a broad weight update margin (i.e., dynamic range (DR)) are required for effective and speedy processing of parallel architecture and unorganized data. This research uses poly(norbornene-co-5-vinyl-2-norbornene), a cross-linked vinyl-added polynorbornene copolymer dielectric layer based on thiol-ene photoclick chemistry, to create a neuromorphic transistor with a high synaptic weight and broad dynamic range. Indium gallium zinc oxide with polymer treatment. The click reaction of the ultraviolet photoinduced thiol-ene polar cross linker pentaerythritol tetrakis(3-mercaptopropionate) (PETMP) generates free -OH groups in the insulator, activating the slow molecular depolarization effect on the IGZO semiconductor. An extensive and methodical research of the characteristics at the boundary between mating the cross-linked polymer insulator, IGZO channel showed impressive neuron behavior operation with a big channel conductance (~0.5 mS), wide dynamic range (~6200), and cycle operating stability at 104 successive pulses, resulting in accuracy of ~87% based on MNIST simulation.