二維層狀材料具有高可撓性、高操作頻率以及低功耗等特性，因此被認為有機會取代傳統矽，成為新一代的半導體材料。除了較為常人所知的石墨烯(Graphene)、過渡金屬二硫族化物(Transition metal dichalcogenides, TMDCs)，三六族層狀化合物半導體的研究也逐漸浮上檯面。其中硒化銦(InSe)材料亦開始被廣泛研究，由於其擁有極小的有效電子質量及適當的能帶大小，具有極高電子遷移率的硒化銦材料，極有可能成為未來半導體產業的核心材料。

與黑磷(Black phosphorus)相似的化學活性造成硒化銦非常容易與大氣中的水、氧分子反應而使元件特性的下降，依據電性量測結果可以觀察到在大氣中氧化之硒化銦場效電晶體擁有極大的遲滯現象，文獻探討中卻鮮少有將其應用在非揮發性記憶體。因此本論文以硒化銦為通道使用金屬遮罩以定義電晶體電極，製成背閘極硒化銦場效電晶體並量測其基本電性及非揮發性記憶體特性。量測結果呈現濕氧氧化7小時的元件擁有較好的非揮發性記憶體特性，其擁有優秀的重複抹寫(Cycling endurance)能力，並展現長時間維持將近2個數量級的電荷儲存(Retention)能力。在未照光環境下，電子遷移率為82 cm ^2/Vs。照有光強度10 mW/cm^2、波長405 nm之紫光環境下，在$ Vgs = 75V時，元件呈現最大的光響應大約為43 A/W。

Two-dimensional layered materials have characteristics such as high flexibility, high operating frequency, and low power consumption, so they are considered to have the chance to substitute traditional silicon process as a new generation of semiconductor materials. Group III-VI compound semiconductors are one class of important 2-D materials. Among them, InSe has been widely studied. InSe is a promising material because of its small effective electron mass and appropriate band gap, with extremely high electron mobility.

Chemical activity of InSe, which is similar to black phosphorus, makes it easily react with water and oxygen molecules in the atmosphere, decreasing the performance of the device. According to the results of electrical measurements, InSe devices oxidized in the atmosphere show a large current hysteresis, but few of them have been used as non-volatile memory in the literature. Therefore, in this thesis, a shadow mask is used to define the source and drain. The back gate InSe FET is fabricated then the basic electrical and non-volatile memory characteristics are measured. The measurement results show that the device with wet oxidation for 7 hours has better non-volatile memory characteristics. It has excellent cycling endurance ability and charge storage ability which maintains nearly 2 orders of magnitude with high stability. In the dark state, the electron mobility is 82 cm ^2/Vs. Under light irradiance of 10 mW/cm^2 and wavelength of 405 nm, the device exhibits a maximum photoresponsivity of 43 A/W at Vgs = 75V.

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