閘極控制型金屬-絕緣層-半導體穿隧電晶體電流特性與機制之研究

Study of the Current-Voltage Characteristics and Mechanisms of Gate-Controlled Metal-Insulator-Semiconductor Tunnel Transistor

詹前修(Chian-Hsiu Chan)

指導教授 ： 胡振國

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201801186

摘要

本篇論文主要在探討閘極控制型金屬-絕緣層-半導體穿隧電晶體之電流特性與機制。此元件為一同心圓之結構，元件中心之金屬-絕緣層-半導體穿隧二極體本身的電流對於鄰近區域之擴散電流變化相當敏感。因此，藉由鄰近之環狀電極電壓的調變，我們可以控制流入中心的擴散電流並進一步的控制中心二極體的電流。此元件擁有電晶體之電流特性，並能做更進一步的討論。
我們將閘極控制型金屬-絕緣層-半導體穿隧電晶體之電流特性分為兩種類型，分別對應到不同的氧化層厚度，也對應到不同的操作機制。不同類型中閘極電流所扮演的角色有所不同，因而導致了電流特性與機制的不同。薄型的元件由於閘極漏流過大，導致最終電流增益不夠理想，因此我們選用氧化層較厚的元件對於其電晶體特性做更進一步的研究。為了得到更好的電晶體特性，我們探討了電極間距以及氧化層厚度對於電流增益的影響。實驗證明，較小的間距能夠增強電極間耦合效應，並有效的增加電流增益。氧化層厚度的增加亦能得到更佳的電流增益。因此，閘極控制型金屬-絕緣層-半導體穿隧電晶體能藉由適當的元件設計，有效的提升其電流特性。

關鍵字

金氧半穿隧二集體 ； 電晶體 ； 耦合效應

並列摘要

In this thesis, the current-voltage characteristics and mechanisms of a gate-controlled metal-insulator-semiconductor (MIS) tunnel transistor has been investigated.
This device is a concentric circles structure. The current of the inner MIS tunnel diode is sensitive to the diffusion current from the neighbor region. Hence, by varying the bias of the surrounding gate, electron flux from gate to the inner circle will change and the current of the inner circle will also change. It shows a transistor characteristic and can be further discussed.
The current-voltage characteristics of a gate-controlled MIS tunnel transistor can be divided into two types by the oxide thickness. We also discussed the mechanisms of these two types. Gate current plays an important role in the ID-VG characteristics and decides types of the device. Gate leakage in thinner type devices is too large and leads to a low Ion/Ioff ratio. Hence, thicker type device is clearly a better choice for the application as a transistor due to its relatively lower off current and higher Ion/Ioff ratio. We also discussed the effects of electrode separation and oxide thickness of the transistor characteristics. It was found that the reduction of electrode separation can enhance the couple effect and lead to a larger Ion/Ioff ratio. A higher Ion/Ioff ratio was found in a device with a thicker oxide. Hence, by a proper design of the gate-controlled MIS tunnel transistor, we can effectively improve the performance of this device.

並列關鍵字

MIS tunnel diode ； transistor ； couple effect

參考文獻

[1] D. Kahng and M. M. Atalla, “Silicon-silicon Dioxide Field Induced Surface Device,” in IRE-AIEE Solid-state Device Res. Conf., Pittsburgh, 1960.

[2] M. A. Green, F. D. King and J. Shewchun, “Minority carrier MIS tunnel diodes and their application to electron- and photo-voltaic energy conversion—I. Theory,” Solid-State Electronics, 1974, Vol. 17, pp. 551-561.

[3] J. Shewchun, M. A. Green and F. D. King, “Minority carrier MIS tunnel diodes and their application to electron- and photo-voltaic energy conversion—II. Experiment” Solid-State Electronics, 1974, Vol. 17, pp. 563-572.

[4] M. A. Green and J. Shewchun, “Capacitance properties of MIS tunnel diodes,” Journal of Applied Physics 46, 5185, 1975.

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