本論文主要探討伽瑪射線和中子輻射對碳化矽元件的影響，伽瑪射線會對半導體材料造成游離效應，中子輻射則對半導體材料造成位移損傷破壞晶格結構。
碳化矽材料有好的抗輻射能力，但元件不一定有好的抗輻射能力，論文中會使用蕭基二極體、金氧半電晶體和電容器等等來進行量測，以觀察元件的變化。觀察到伽瑪射線會在碳化矽跟氧化層的介面處引進氧化層捕捉電荷改變其閾值電壓，且使介面陷阱密度提升。中子輻射則是對元件造成整體的位移損傷，在中子通量為5×1014n/cm2時，會使n type飄移區補償了2.75×1015cm-3到3.91×1015 cm-3濃度，造成飄移區濃度較淡的元件帶來災難性的損壞，且透過深能阱暫態能譜觀察到飄移區有缺陷的存在。
碳化矽元件應調整閾值電壓的數值及設計較薄的氧化層使元件對伽瑪射線有抵抗力。碳化矽元件應把濃度較淡的區域調高其濃度來抵抗中子輻射。

This thesis investigates the effects of gamma ray and neutron radiation in 4H-SiC devices. It is commonly accepted that gamma ray leads to ionization effect, and neutron radiation causes displacement damage to destroy the crystal structure on semiconductor material.
Even though silicon carbide has good radiation resistance, but devices might suffer from different mechanisms can behave differently. In this study we measure 4H-SiC Schottky diodes, MOSFETs and capacitors to investigate their variation. It is observed that gamma ray introduces oxide trapped charge at the SiC/SiO2 interface to change the threshold voltage and increase the density of interface traps. Neutron radiation brings the overall displacement damages to the bulk of the devices. When the neutron flux is 5×1014 n/cm2, 2.75×1015cm-3 to 3.91×1015cm-3 of the doping concentration in the n-type drift layer is compensated and causes catastrophic damage to the devices. The defects in the drift region has also been observed by deep level transient spectroscopy.
It is recommended that 4H-SiC devices should adjust the threshold voltage value and consist a thin gate oxide layer to be gamma ray resistant. 4H-SiC devices should increase the doping concentration in order to be robust against the neutron irradiation

中文摘要 I
Abstract II
目錄 II
圖目錄 VII
表目錄 XIII
第一章序論 1
1.1 碳化矽材料簡介 1
1.2 伽瑪射線(gamma ray) 2
1.3 中子輻射(neutron radiation) 3
1.4 文獻回顧 4
1.4.1 伽瑪射線對碳化矽影響 4
1.4.1 中子輻射對碳化矽影響 5
1.5 研究動機與論文大綱 5
第二章選用的元件介紹及實驗設計 8
2.1 市售的封裝功率元件介紹 8
2.1.1 垂直型雙佈植金氧半電晶體 9
2.1.2 垂直型溝槽式閘極金氧半電晶體 9
2.1.3 接面位障蕭基二極體 10
2.2.2 未封裝的元件介紹 11
2.2.1 垂直型電容器 11
2.2.2 蕭基二極體 12
2.2.3 霍爾量測用的試片 13
2.3 總游離劑量的輻射照射測試 14
2.4 位移損傷的輻射照射測試 14
2.5 深能阱暫態能譜量測介紹 15
第三章總游離劑量輻射照射量測結果 27
3.1 市售的封裝功率元件量測 27
3.1.1 蕭基二極體量測 27
3.1.2 金氧半電晶體量測 29
3.1.3 不同方向照射的比較 32
3.2 未封裝的功率元件量測 33
3.2.1 電容量測 33
3.2.2 蕭基二極體量測 34
3.2.3 霍爾量測 34
3.3 退火修復機制 35
第四章位移損傷輻射照射量測結果 54
4.1 市售的封裝功率元件量測 54
4.1.1 蕭基二極體量測 54
4.1.2 金氧半電晶體量測 57
4.2 未封裝的功率元件量測 62
4.2.1 電容量測 62
4.2.2 蕭基二極體量測 63
4.2.3 霍爾量測 64
4.3 退火修復機制 65
4.4 深能阱暫態能譜量測 65
第五章結論與未來展望 87
參考文獻 88

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