Study Of Organic Memory Device-OFET With Floating Gate And Ferroelectric Dielectric

As an important branch of organic semiconductor device, organic memory device has got a great attention. It is quite suitable for organic memory device to be used in all organic device and flexible electronic products, owing to its lightweight, low-cost and flexibility. We need outstanding performance organic storage device with simple manufacturing process urgently.The purpose of this paper is to search for effective methods which make OFET an effective memory device through changing the threshold voltage of OFET. Main job of this paper is divided into two parts. One part is the study of Floating Gate OFET memory device which is innovatively proposed. We reduce the threshold voltage of OFET by introducing a floating gate into traditional OFET, which make Floating Gate OFET has storage characteristic. The other part is the study of Ferroelectric Dielectric OFET memory device. The SiO2 layer is replaced by ferroelectric layer in Ferroelectric Dielectric OFET memory device. The variation of device threshold voltage is due to polarization effect of ferroelectric material. The transfer characteristics of both two OFET memory devices are simulated, then the threshold voltages after "programming" and "erasing" are given. We also illustrate the mechanism of threshold voltage variation theoretically. The research results show that the threshold voltage of Floating Gate OFET with a pentacene layer is decreased by 4 V, due to the effect of the charge on floating gate. Because of the difference of polarization directions, the threshold voltage of Ferroelectric OFET with a PZT dielectric layer changes a lot before and after programming. These two memory devices show large and available memory windows, they both are suitable for storage devices. By comparison, the manufacturing process of Floating Gate OFET memory device is much simpler and storage characteristic is much better than Ferroelectric OFET. So Floating Gate OFET is more suitable for storage device.