| 摘要: | 電洞是電化學蝕刻時的必要因素，然而N型半導體的主要載流子為電子，因此一般來說N型半導體難以透過普通的電化學方式進行蝕刻，需要額外的輔助讓電化學反應介面產生電洞造成蝕刻。本研究透過導電高分子在晶圓進行晶背電化學實驗時可以保護元件不受化學溶液或是碰撞損害，可以運用到晶片的晶背研磨製程，此外也能改善半導體接面間的能隙及空乏區，使電洞傳導率變快，實驗以雙蝕刻槽作為主要實驗設備，將導電高分子PEDOT/PSS塗佈於N型矽上，形成N/PEDOT/P異質接面結構，而無需加入金屬片，之後在暗室中施加電場進行電化學實驗。實驗結束後，可直接拆除輔助的P型矽，並確保N型矽上的導電高分子薄膜保持無汙染。實驗將使用不同摻雜濃度的N型矽與P型矽進行不同組合的PN接面進行電化學蝕刻。蝕刻完成後，將進行紫外光照射、場發射掃描式電子顯微鏡(SEM)和光致發光光譜儀(PL)分析，並通過實驗過程中電壓電流的變化繪製趨勢圖以觀察效果。從SEM圖和電壓電流圖的分析中可以發現，塗佈導電高分子的試片蝕刻速率更快，電流導通速度也更明顯提升，且結構略有不同。在光致發光方面，亮度也更高，且通過提高試片的摻雜濃度，實驗效果更為突出。;Hole is a necessary factor in electrochemical etching. However, the main carrier of N-type semiconductors is electrons, so it is generally difficult for N-type semiconductors to be etched by ordinary electrochemical methods, and additional assistance is needed to generate hole in the electrochemical reaction interface to cause etching. In this study, conductive polymers can protect the components from chemical solution or collision damage when conducting electrochemical experiments on the wafer back, which can be applied to the wafer back grinding process. In addition, the energy gap and void region between semiconductor junctions can be improved to make the hole conductivity faster. The experiment uses double etching slots as the main experimental equipment. The conductive polymer PEDOT/PSS is coated on N-type silicon to form N/PEDOT/P heterogeneous junction structure without adding metal sheet, and then an electric field is applied in a dark room for electrochemical experiments. After the experiment, the auxiliary P-type silicon can be removed directly, and the conductive polymer film on the N-type silicon can be ensured to remain pollution-free. In the experiment, the PN junction with different combinations of N-type silicon and P-type silicon with different doping concentrations will be electrochemical etched. After the etching is completed, ultraviolet irradiation, field emission scanning electron microscope (SEM) and photoluminescence spectrometer (PL) analysis will be carried out, and trend graphs will be drawn to observe the effect through the changes of voltage and current during the experiment. From the analysis of SEM and voltage-current diagram, it can be found that the etching rate of the test piece coated with conductive polymer is faster, the current conduction speed is also more obvious, and the structure is slightly different. In terms of photoluminescence, the brightness is also higher, and the experimental effect is more prominent by increasing the doping concentration of the test piece. |
