NIR and visible light dual-mode organic electrolyte-gated phototransistors via ionic doping
발표자
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초록
내용
Herein, we suggest a new concept of phototransistor, organic electrolyte-gated phototransistor (OEGP), which has a unique structure that adopts electrolytes as an insulating layer. Anions are injected into the p-type polymer semiconductor according to the gate voltage, which leads the bulk of active layer to be doped. Through this ionic doping process, not only does the channel conductance increase, but the absorption spectrum of the doped active layer is also shifted from the neutral to polaron band. Therefore, it is possible to detect the generated excitons of polaron band as a current, if the process of separation and transportation of electron-hole pairs within the device is carried out smoothly.
It is well known that poly(3-hexylthiophene) (P3HT) has an absorption spectrum of neutral band at 400 ~ 600 nm and polaron band at 700 ~ 900 nm.1 Taking advantage of this, we designed OEGP which can detect both NIR-visible regions reversibly while conventional P3HT based photonic devices mainly detect only the visible light region.