具金屬光柵增強型之量子點紅外線偵測器

Abstract

從一些文獻得知，表面電漿子可以增強量子點紅外線偵測器的光響應。在本篇論文中，我們在砷化鎵元件表面製作金屬光柵，使金屬與砷化鎵的界面產生表面電漿子，再針對量子點紅外線偵測器吸收的波長，對金屬光柵做適當的週期性結構，使激發的表面電漿子其共振波長與元件吸收波長相同，讓光響應能最有效率的提升。我們更進一步觀察到，當表面電漿子越靠近元件主動層，其偵測光的效率也會上升。最後，我們實際在量子點紅外線偵測器上做出Metal photonic crystal(MPC)以及Corrugated metal surface(CMS)兩種不同結構的週期性金屬光柵並進行光響應量測，結果發現CMS結構的量子點紅外線偵測器有高達10倍光響應的提升，遠遠高於MPC結構，對整體元件的表現特性明顯大幅提高。

It’s known that the surface plasmons can enhance the responsivity of quantum dot infrared photodetectors. In this thesis, we make the metal grating on QDIPs, which can generate surface plasmons between metal and GaAs. Then, we make the metal grating with the appropriate periodic structure for the absorption wavelength of QDIPs, which is the same as the resonant wavelength because of exciting surface plasmons. The responsivity of QDIPs can be the most efficient upgrade. We further observed that when the surface plasmon closer to the QDIPs active layer, the detection efficiency of light will rise. Finally, we actually make two different structures periodic metal grating on the quantum dot infrared photodetectors, metal photonic crystal (MPC) and corrugated metal surface (CMS) , and then we measure the responsivity of QDIPs. The results show that the CMS structure on QDIPs are up to 10 times improvement in the responsivity, and much higher than the MPC structure, the overall performance characteristics of QDIPs significantly increase substantially.