矽基量子元件與積體電路通常內部具有不同摻雜分佈的半導體。在傳統的掃描探針顯微鏡(SPM)技術中，掃描電容顯微鏡(SCM)是測量半導體載子電容的常用方法，然而，SCM測量對樣品有嚴格的限制，例如樣品表面需要有均勻的薄氧化層。
為此，我們開發了基於微波系統的振幅調製靜電力顯微鏡(AM-EFM)和邊帶靜電力顯微鏡(Sideband-EFM)。這些技術涉及灌入兩種不同頻率的微波，其中一種是高頻載子頻率(約300 MHz)來驅動半導體的較佳載子移動，另一種是調製頻率(約7 kHz和2 kHz) 作為外接鎖相放大器的偵測參考訊號。在定電壓(0 V)下，對埋層結構特製階梯式樣品(Infineon dopant calibration sample)進行非破壞性電容量測。Sideband-EFM由於只考量探針針尖正下方的微分電容梯度，因此可以增加靈敏度。
接著，將摻雜濃度取對數與訊號大小歸一量化，結合有限元素分析法(Finite Element Method, FEM)商用模擬軟體COMSOL Multiphysics 6.2和理論修正公式擬合(Fitting)，這三者可以互相吻合。一方面可以藉由定量模型推測未知半導體的載子濃度區間；另一方面，這樣可以將微波EFM系統的最佳分辨載子濃度提高至1016~1020 cm-3 。此外，進一步的模擬解釋了不同探針效應或環境因素對電容因子的影響，當掃描過程中探針半徑和樣品氧化層厚度…等尺寸的影響，經過歸一化後處理後，結果都是一致適用的。
進一步，可以根據Sideband-EFM偵測到微波訊號源的側峰Sideband peak強度和穩定性，建立一個標準判斷是否輸入了高頻微波。通過SMA線阻抗匹配後，成功實現載子頻率可調控性，最高可達7.7 GHz的高頻。同時也可以將高頻微波注入二維半導體WSe2和磁性樣品的應用。
最後，我們自行開發了基於探針下方量測阻抗(Z)，並直接換算成電容與電阻的微波阻抗顯微鏡(MIM)。該技術使用網路分析儀(VNA)來量測S11反射率中的阻抗(Z)，並通過電腦上的Labview偵測原子力顯微鏡(AFM)的觸發(Trigger)訊號，進一步操控VNA取得相對應的數據mapping圖。這使得我們能夠在更寬頻的量測，擴展至非半導體材料的導電度性質。

Silicon-based quantum devices and integrated circuits usually have different doping distributions inside. In traditional Scanning Probe Microscopy (SPM), Scanning Capacitance Microscopy (SCM) is a commonly used method to measure carrier capacitance. However, SCM measurements have strict limitations on the sample, such as requiring a uniform thin oxide layer on the sample surface.
Therefore, we develop microwave systems Amplitude Modulation Electrostatic Force Microscopy (AM-EFM) and Sideband Electrostatic Force Microscopy (Sideband-EFM), and Sideband-EFM can enhance sensitivity. These techniques use two different frequency microwaves, one being a high-frequency carrier frequency (about 300 MHz) to drive better carrier mobility, and the other being a modulation frequency (about 7 kHz and 2 kHz) as a reference signal for an external lock-in amplifier. These methods allow for non-destructive capacitance measurements of Infineon dopant calibration sample with buried structures. Next, the normalized signal magnitude with the logarithm of the doping concentration curves are combined with Finite Element Method (FEM) and theoretical formula fitting. Quantitative model can be used to speculate the carrier concentration range of unknown semiconductors. It also allows the best resolvable carrier concentration to be improved to 1016~1020 cm-3.
Furthermore, based on the intensity and stability of the sideband peak, a standard can be established to determine whether high-frequency microwaves have been input. This technique can also be applied to 2-D semiconductors like WSe2 and magnetic samples like (Pt/Co)4.
Finally, we developed a Microwave Impedance Microscopy (MIM), which based on the impedance (Z) directly converts into capacitance (C). This technique uses a vector network analyzer (VNA) to measure the impedance (Z) from reflectivity (S11) reflectance. It is detected by AFM trigger signal through Labview on a computer, further controlling the VNA to obtain corresponding data mapping images. This allows us to measure conductivity properties in a broader frequency range, extending to non-semiconductor materials.

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