| 摘要: | 本研究接續2017 年起所執行之低溫多孔矽電化學蝕刻研究， 初步實驗成果顯示自由載流子吸收對於電化學蝕刻有相當大的影響。2017 年本研究團隊發現紅外光雷射以自由載流體吸收效應來抑制蝕刻，因此更進一步選用紅外波長1310-1550 nm 雷射照射，且將蝕刻槽周圍環境降低溫度至零下74°C，探討以自由載流體吸收效應及低溫效應雙重抑制蝕刻方式形成次奈米晶（~ 0.5 nm）的可行性。初步實驗結果發現以長波長雷射照射能抑制蝕刻，自雷射照耀點處，往外有波浪狀細窄圖樣產生，預期有突破性的發現，在光致發光實測中能以UV 光激發，並無一般多孔矽光致發光現象，研判激發之光波長有可能不在可現光範圍內，這假設須作更進一步研究分析。本計畫延續 2017 年研究，不但分析其活化能，推導出蝕刻速率與光鈍化活化能之間的關係式，更佐以研究相關文獻，期待藉由抑制機制提出多孔矽均勻分佈態形成之模型，提出解釋電化學蝕刻如何使矽晶表面形成均分型態之深井狀結構（迄今尚未有公認被接受的解釋）。如此除了有學理上的研究之外，還有實際的工業應用：透過雷射功率、蝕刻速率的控制發展可取代在微機電技術部份元件製作中，顯影製程的塗佈光阻與移除光阻的步驟。這技術縮短製程時間與降低成本，實現 3D 驅動元件的製作，更是期待能對矽光子積體核心元件材料製作技術產生一些革命性的突破。 ;In this study, the low temperature porous silicon electrochemical etching study carried out since 2017 has been carried out. Preliminary experimental results show that the free carrier absorption has a considerable influence on the electrochemical etching. In 2017, the research team found that the infrared laser radiation suppresses the etching with the free-carrier absorption effect. Therefore, we further selected the laser with infrared wavelength of 1310-1550 nm and lowered the ambient temperature of the etching bath to minus 74 ° C Feasibility of formation of sub-nanocrystalline (~ 0.5 nm) by dual-suppression etching with free-carrier-loading effect and low temperature effect. Preliminary experimental results show that the long-wavelength laser irradiation can inhibit the etching, since the laser shine point, there are wavy narrow pattern generated outside, is expected to have a breakthrough discovery, in photoluminescence measured with UV light excitation, and There is no general porous silicon photoluminescence phenomenon, the wavelength of the light to stimulate the assessment may not be in the range of light, which assumes the need for further research and analysis. This project continues the 2017 study, not only analyzing its activation energy, deriving the relationship between the etching rate and the photoactivation activation energy, but also studying the relevant literature and expecting to propose a model of uniform distribution of porous silicon distribution by the inhibition mechanism , Proposed a deep well-like structure that explains how electrochemical etching makes a homogeneous surface of the silicon crystal (so far not yet accepted as accepted). In addition to the theoretical study, there are practical industrial applications: the control development of the etching rate through the laser power can replace the fabrication of some components in MEMS, the photoresist coating and the removal of light in the development process Blocking steps. This technology to shorten the manufacturing process and reduce costs, to achieve the production of 3D driver components, but also look forward to the silicon photonic integrated core device material production technology to make some revolutionary breakthroughs. |
