本論文研究具電壓調變波型能力之雙波段紫外光檢測器。該檢測器由MgZnO、ZnO、Ga2O3、GaN與SiO2成分所構成，並分別由射頻磁控濺鍍法、金屬有機物氣象沉積法、電漿輔助化學氣象沉積法製作。對於ZnO紫外光檢測器，當退火300度時在5V能夠有最好的響應約7.27 × 10-3，且位於波長380 nm。對於Ga2O3紫外光檢測器，800度退火在5V能有最好紫外光對可見光拒斥比的特性，且響應最大值的波長位於波長250 nm。對於MgZnO紫外光檢測器，不論使用10 %或20 %靶材，晶格品質跟實際的鎂含量都會隨著退火溫度提升而提高，而最好的條件在退火攝氏700度時。另外兩種含量的波長吸收邊緣分別在337 nm與310 nm。對於雙波段MgZnO紫外光檢測器，則必需插入SiO2用以避免鎂擴散導致邊界模糊，以及將不同吸收波段在高與低電壓間分離。而波長吸收的分別是310 nm到320 nm，總共位移了10 nm。於此，在更大波段位移的設計則繼續沿用插入SiO2的設計。對於具電壓調變波型能力之雙波段紫外光檢測器(UVB到UVA)，在MgZnO/SiO2/ZnO結構中，具有200 nm MgZnO厚度的樣本有較明顯的雙波特性。吸收波長邊緣從310 nm (UVB)到365 nm (UVA)共位移了55 nm。對於具電壓調變波型能力之雙波段紫外光檢測器(UVC到UVB)，在Ga2O3/MgZnO結構中，具未進行退火Ga2O3樣本有較明顯的雙波特性。吸收波長邊緣從250 nm (UVA)到320 nm (UVB)共位移了70nm。此外樣本在Ga2O3與MgZnO間插入25 nm厚的SiO2，可將MgZnO的吸收波段延後至24V才開始主導。對於具電壓調變波型能力之雙波段紫外光檢測器(UVC到UVA)，在MgZnO/SiO2/ZnO結構中，具有100 nm SiO2厚度的樣本意外地出現帶通型的吸收波型，而將SiO2厚度提升至400nm則可直接將其視為絕緣層，所有的光電子都來自Ga2O3，而在200 nm SiO2厚度且其Ga2O3在攝氏300度退火下的樣本有較明顯的雙波特性。吸收波長邊緣從250 nm (UVC)到365 nm (UVA)共位移了115 nm。

In this dissertation, the voltage-tunable dual-band UV PD has been investigated. The dual-band UV PD consisted of MgZnO, ZnO, Ga2O3, GaN, and SiO2, which was grown by RF magnetron sputter, MOCVD, PECVD, respectively. For the ZnO UV PD, the best thin-film quality was at 300C annealing and to had the highest PDCR to 1810.18 at 5V. And due to better crystal quality, the device annealing at 300 ℃ exhibited the best responsivity at 5V, which was 7.27 × 10-3, and was located at 380 nm. For the Ga2O3 UV PD, the annealing condition at 800 ℃ had the best performance of ultraviolet to visible light rejection ratio, and the maximum of responsivity was located at 250nm. For the MgZnO UV PD, no matter used 10% Mg content target or 20% Mg content target, the cristal quality and real Mg composition were increased as arisen annealed temperature. And the best condition was annealing at 700 ℃. Moreover, the wavelength absorbed edge was 337 nm and 310 nm, which device made by 10% and 20% Mg content target, respectively. For the MgZnO dual-band UV PD, the structure should be inserted as a blocking layer to prevent the Mg atom diffusion, on the one hand. On the other hand, it separated the mainly absorbed wavelength between low and high bias voltage; otherwise, the edge between layers with different Mg composition would be blurred. The edge of the absorbed wavelength was shifted about 10 nm, which from 310 nm to 320 nm.
Based on this, the SiO2 inserting layer was considered in our voltage-tunable UV PD design, which was design to cross different ranges of absorbed wavelength. For voltage-tunable UVB to UVA dual-band UV PD, the MgZnO/SiO2/ZnO dual-band UV PD had an obvious voltage-tunable dual-band performance with 200 nm MgZnO thickness. And the edge of the absorbed wavelength shifted about 55 nm, from 310 nm (UVB) to 365nm (UVA). For voltage-tunable UVC to UVB dual-band UV PD, the Ga2O3/MgZnO dual-band UV PD had an obvious voltage-tunable dual-band performance without Ga2O3 annealing. And the edge of the absorbed wavelength shifted about 70 nm, which from 250 nm (UVC) to 320nm (UVB). Furthermore, inserted 25 nm SiO2 between Ga2O3 and MgZnO could extend the MgZnO absorbed wavelength to appear at 24 V. For voltage-tunable UVC to UVA dual-band UV PD, the Ga2O3/SiO2/GaN dual-band UV PD accidentally exhibited a band-pass liked performance at 600 ℃ annealings, which with 100nm SiO2 thickness. When the thickness of SiO2 increased to 400 nm, all of the photon-electrons of devices were generated from Ga2O3. The Ga2O3/SiO2/GaN dual-band UV PD had an obvious voltage-tunable dual-band performance with 200 nm SiO2 thickness and 300 ℃ Ga2O3 annealings. And the edge of the absorbed wavelength shifted about 115 nm, which from 250 nm (UVC) to 365nm (UVA).

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