鈣鈦礦與鐵磁層交互作用與磁阻元件製作

Abstract

在先前的研究中，我們發現在FePd薄膜上成長的MAPbBr3會是離散圓盤狀的鈣鈦礦，對於製作元件來說這會導致裸露的FePd薄膜讓電子直接短路，於是在本研究中我們利用了氧化鋁(AlOx)作為插層，在鈣鈦礦MAPbBr3與鐵磁層Co和Fe中間插入AlOx薄膜，成功成長出連續性且均勻的MAPbBr3薄膜，根據原子力顯微鏡顯示其粗糙度約為15 nm，磁光柯爾顯微鏡的結果也顯示出旋塗上MAPbBr3薄膜不會對下方鐵磁層磁性有所影響。在近期的研究顯示出CsPbBr3相對於MAPbBr3具有較高的熱穩定性，且我們發現CsPbBr3旋塗於金屬層上為連續均勻的薄膜。根據上述的結果，鈣鈦礦CsPbBr3可能具有高的應用潛力。因此我們對於CsPbBr3與鐵磁層的交互作用進行研究。我們在方格陣列Co薄膜厚度分別為6 nm、10 nm、12 nm與16 nm旋塗上CsPbBr3，此四種樣品在旋塗CsPbBr3前後的矯頑場均無改變，接著觀察到6 nm與10 nm樣品的矯頑場會隨著第一次雷射光照射的時間有逐漸降低的趨勢，其中10 nm的樣品在照射24分鐘後會量測不到磁性，然後在關閉雷射後放置一小時並再次照光30分鐘後，此時的矯頑場會提升至74.5 Oe，而12 nm與16 nm的樣品則有相反的現象，在雷射光照射下，樣品的矯頑場會隨著雷射照射時間有逐漸增加的趨勢，其中12 nm的樣品在照射28分鐘後會量測不到磁性，而在關閉雷射一段時間後矯頑場會提升至150 Oe，從結果也能發現當雷射光照射時，如果矯頑場有變化且磁性還能被量測到的樣品，在放置一段時間後，矯頑場並不會有回復的特性，根據原子力顯微鏡也能觀察到當給予兩次30分鐘的雷射照光時，粗糙度會從17.9 nm提升至22 nm與27.6 nm。因此，我們推測藍光雷射的照射會改變CsPbBr3的特性，同時也會改變下方的磁性金屬層。In the previous study, we knew that MAPbBr3 grown on FePd film would be a discrete disc-shaped structure. For device production, this will cause the exposed FePd film to directly short-circuit the electrons. Because of this reason, we used aluminum oxide (AlOx) as an interlayer. We inserted an AlOx film between the MAPbBr3 and the ferromagnetic layer for Co and Fe. The results showed that a continuous and uniform MAPbBr3 film was successfully grown on AlOx film. According to the atomic force microscope results, the roughness of MAPbBr3 was about 15 nm. Also, magneto-optical Kerr effect microscope showed that spin-coated MAPbBr3 will not affect the magnetic properties of the underlying ferromagnetic layer. In recent studies have shown that CsPbBr3 has higher thermal stability than MAPbBr3. And we found that CsPbBr3 spin-coated on the metal layer is a continuous uniform film. Therefore, perovskite CsPbBr3 has better forward future. We study the interaction between the CsPbBr3 and the ferromagnetic layer. We spin-coated CsPbBr3 on the square array Co film which thicknesses of 6 nm, 10 nm, 12 nm and 16 nm. The magnetic coercivity of these four samples are unchanged before and after CsPbBr3 spin-coated on them. The coercivity of 6 nm and 10 nm samples would gradually decrease when first time for laser irradiate. Among them, the magnetism of 10 nm Co was unmeasured after 24 minutes of irradiation. Then after turned off laser, waited it for 1 hour and irradiated it again for 30 minutes. At this time, coercivity would increase to 74.5 Oe. The 12 nm and 16 nm samples had the opposite phenomenon. Under the laser irradiation, as the laser irradiation time increase, coercivity tended to become larger. Among them, the magnetism of 12 nm Co was unmeasured after 28 minutes of irradiation. After turning off the laser for a while, coercivity would increase to 150 Oe.Based on these results, we presented the coercivity of Co was changed after laser irradiated, and which is no recovery when turned off the laser. According to the AFM results, we observed that when 30-minute laser beams are given twice, the roughness of CsPbBr3 would increase from 17.9 nm to 22 nm and 27.6 nm. Therefore, we speculate that the irradiation of the blue laser will change the characteristics of CsPbBr3 and change the magnetic metal layer.