EDS結合電子顯微鏡系統具有許多獨特的優點和半導體檢測的功能，當我們在電子顯微鏡觀察特定的顯微組織時，可以進一步利用X射線能量散佈分析儀，在短短數分鐘時間，完成選定區的材料所含元素的定性、半定量、面掃描及線掃描分析。
市面上販售的EDS所裝配的偵檢器主要可分為二類，第一類為矽(鋰)偵檢器( Silicon Lithium Solid State Detector)，第二類為矽漂移偵檢器( Silicon Drift Detector, SDD)。上述兩種偵檢器均屬於固態偵檢器，均可利用半導體產業的加工方式；但若在相同的偵測面積下相較於矽(鋰)偵檢器，矽漂移偵檢器有較好的能量解析度；而高計數狀況下，若將雜訊一併考慮，矽漂移偵檢器在高計數下也有較好的能量解析度，且矽漂移偵檢器使用致冷晶片，無須定期添加液態氮，有較佳的使用便利性，故本論文採用矽漂移偵檢器作為研究方向。
自製漂移偵檢器愈採用電阻值約為4 kΩ-cm的N型厚矽晶圓來製作元件，藉由保護環( Guard Ring) 、場效電板( Field-Plate)及訊號收集電極保護環等設計，來減少施加高逆向偏壓所帶來的漏電流，同時考慮特性X射線的穿透深度，利用模擬軟體SRIM、TRIM來預測佈植情況，設計超淺佈植( Shallow junction)結構，可收集低能量之X射線，故可提升低能量X射線之能量解析度及元件量子效率值，同時不將場效電晶體整合到SDD上，以減少製程步驟。元件端(Device side)圖形朝著對稱、規律；至於訊號收集電極則放在偵檢器中心，以利電子跑動距離的均等性；由於接點太多，須爬線到外圍圖形以利接線，也考慮了二氧化矽的RC延遲及碰穿電壓。窗口端增大收集面積，以利快速偵測；同時使的無感層變薄，讓更低能量可以被偵測到，提升偵測極限；並加上保護環，隔絕非元件工作區的雜訊。
自製矽漂移偵檢器已被設計、製造、並測試完成，元件電性部分，自製矽漂移偵檢器在製程完善的情況下暗電流為76 pA；透過元件外保護環、場效電板及中心電極保護環等設計，改善了漏電流隨電壓急遽上升的現象(在-120 V時，漏電流為200 nA, 偵測面積:10 mm2)，同時提升了元件之崩潰電壓(-200 V仍未崩潰)，若再降低溫減少熱擾動電子濃度，漏電流便快速降低為2 nA；在偏壓-130 V、前置放大器為1 V/pC、放大器放大倍率20倍時，量測241Am α粒子(5.468 MeV)，已有足夠判斷之特徵峰值出現；55Fe所量測之能譜圖並沒有像241Am α粒子有明顯特徵峰值，除了每顆粒子所帶的能量差了約920倍外(55Fe:5.9 keV, α粒子:5.468 MeV)，同時發現在降低溫、偏壓為:-60 V時，從多通道頻譜分析儀上看來，目前的熱擾動雜訊為25.35 mV(放大倍率為:10)，得到雜訊能量為:56.33 keV，所以SDD元件推測降低溫至250 K減少熱擾動電子(58 pA, 2.75 keV)，才有機會偵測到射源55Fe。

Energy Dispersive X-ray Spectrometer (EDS) is the most common analytical tool in SEM and TEM used for the elemental analysis or chemical characterization of a sample. The most critical part in EDS system is the x-ray detector. In the past, the most solid-state detectors used in X-ray spectroscopy system are made of Si(Li) crystal. The incorporation of lithium atoms into silicon can greatly reduce the space charge from the bulk of silicon and thick detectors could be fabricated and operated at reasonable biasing voltage. The major drawback of Si(Li) detector is that they require hours to cool down by liquid nitrogen to reduce electrical noise before use, and cannot be allowed to warm up during operation. Besides, the increase of Si(Li) detection area will increase the capacitance and electronic noise that will lead to lower response time and sensitivity. There is a trend towards a new EDS detector over past decade, called the silicon drift detector (SDD). The key advantage of the SDD is the very lower anode capacitance compared with conventional Si(Li) detectors of the same active detection area. This unique feature reduces electronic noise and shortens processing shaping time to achieve higher energy resolution and counting rate. Due to the small anode in the SDD the leakage current is so low that the SDD can be operated with moderate cooling simply by Peltier cooler.
The SDDs were fabricated on n-type <111> and a resistivity of more than 4kΩ.cm silicon substrates with a thickness of 400μm. The SDD consists of fully depleted silicon, in which an electric field with a strong component parallel to the surface drives electrons generated by the absorption of x-ray towards a small sized collecting anode. The electric field is generated by a number of increasingly reverse biased cathodes on one side surface of the device. The radiation entrance window on the opposite side is made by a non-structured shallow implanted junction giving a homogeneous X-ray entrance surface over the whole detection area and allows lower energy x-ray can be detected.
SDD comprise non-structured shallow implanted junction and the anode guard ring for improving the energy resolution of detector. First, if the p-n junction is located at deep depth, the thickness of dead layer will to thick. Therefore the non-structured shallow implanted junction allows minimizing the dead layer of detector and also prevents the unnecessary absorption of X-ray by the structure metal layer on the surface of entrance window. Second, the electrons attracted by positive fixed charges at the Si/SiO2 interface are collected by the anode guard ring rather than contributing to the leakage current of detector. It is helpful to reduce leakage current and increasing signal to noise ratio.
Silicon Drift detector for EDS has been designed, fabricated and tested. SDD were characterized to extract critical I-V performance parameter like total leakage current at anode. The value of leakage current is 200 nA with anode guard ring, and reduces to 2 nA with anode guard ring at 15 ℃. Device will not breakdown even bias voltage up to -200 V. The alpha particle can be detected by homemade SDD. This show the device can work well. But the response for detector exposed to the X-ray source will test in the future. Because of the heat sink of chamber is still a problem. The temperature of device just reach 15 ℃ by TE cooler. We predict the leakage current rise by thermal noise will decrease to 58 pA at 250 K. This condition is good enough to detect 55Fe source. The goal of the testing have shown a FWHM at MnKα line of a radioactive 55Fe source of 200 eV at -20 ℃.

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