矽基量子點隧道耦合的虛擬閘極控制模擬

Abstract

近年半導體科技的不斷進步，元件隨著摩爾定律，開始越做越小，使得量子物理效應變得越來越明顯，並在模擬和製程設計方面對現行的測量技術提出了挑戰，因此量子點有望取代現有的半導體技術，並成為成為下一個世代的半導體核心技術。隨著量子點陣列製造設計的複雜性不斷增加，需要開發一個有效率控制閘極的方式，但在開發前，需要透過理論模擬去了解元件特性及如何控制量子點，因此在此論文主要研究由與 TSRI 合作所設計和製造的 Si-MOS 四量子點元件的理論模擬。從理論上利用數值模擬和解析解，可以讓我們對研究中的量子點元件在實驗中提高量子點元件的操控性能和穩定性。具體來說，在我們的模擬中，我們調整實際閘極電壓值並繪製電荷穩定性圖。我們也分析了虛擬閘的概念和應用，旨在促進量子點元件的調製過程。透過採用物理閘極電壓的特定線性組合組成的虛擬閘極，可以消除閘極電壓之間的串擾，從而提高閘極調諧過程的效能和精確度，提高Si-MOS量子點元件的可控性，並有望在未來促進台灣對於器件製造和量子點量子位操縱的發展。

In recent years, with the continuous advancement of semiconductor technology, devices have become increasingly smaller in accordance with Moore's Law. This has made quantum physical effects more prominent and has posed challenges to current measurement techniques in simulation and process design. Quantum dots have been proposed as a promising physical system for implementing a practical quantum computer. As the complexity of quantum dot array fabrication and design continues to increase, it is necessary to develop an efficient method for controlling gate electrodes. However, before development, it is essential to understand the characteristics of the devices and how to control the quantum dots through theoretical simulations. Therefore, this thesis primarily focuses on the theoretical simulation of Si-MOS quadruple quantum dot devices designed and fabricated in collaboration with TSRI. Through numerical simulations and analytical solutions, we aim to enhance the control performance and stability of the quantum dot devices under study in experiments. Specifically, in our simulations, we adjust the actual gate voltage values and plot the charge stability diagram. We also analyze the concept and application of virtual gates, aiming to facilitate the modulation process of quantum dot devices. By employing virtual gates composed of specific linear combinations of physical gate voltages, we can eliminate the crosstalk between gate voltages, thereby enhancing the effectiveness and precision of the gate tuning process and improving the controllability of Si-MOS quantum dot devices, and hopefully promote Taiwan's development in device fabrication and quantum dot qubit manipulation in the future.