芳香族高性能高分子合成與記憶體元件應用之研究

Abstract

本論文分成五個章節，第一章為總體序論。第二章由4,4’-dihydroxyltriphenyamine分別與2,5-bis(4-fluorophenyl)-1,3,4-oxadiazole及4,4’-(hexafluoroisopropylidene)bis(benzoylchloride)合成新型聚醚OXPE及新型聚酯6FPET作為記憶體主動層材料。為了探討連結基團對於記憶體性質的影響，此章節同時合成聚醯胺6FPA、聚醯亞胺6FPI及同分異構物6FPI’並探討其記憶體性質。為了更系統化的探討連結基團對記憶體性質的影響，皆含有sulfonyl為受體但具有不同連結基團的DSPE、DSPET、DSPA及DSPI也加入討論。從結果顯示，具有較柔軟連結基團、較低LUMO能階及較高偶極矩的高分子會具有較長的記憶時間。第三章合成了一系列具有不同強度拉電子基團酸酐之聚醯亞胺5Ph-ODPI、5Ph-DSPI、5Ph-PMPI及5Ph-NPPM與先前發表的5Ph-6FPI一起比較。因為不同強度拉電子基團導致的不同HOMO值、LUMO值及偶極矩導致了多樣性的記憶體性質。隨著拉電子能力的增強，記憶體的記憶時間增長: 5Ph-ODPI不具有記憶體特性、5Ph-6FPI具有動態隨機存取記憶體(DRAM)性質、5Ph-PMPI具有靜態隨機存取記憶體(SRAM)的性質、5Ph-NPPI則具有一次寫入多次讀取(WORM)的性質。此外，5Ph-DSPI雖然LUMO值介於5Ph-PMPI及5Ph-NPPI間，但其高偶極矩(5.45D)導致了他的非揮發性WROM性質。第四章則合成具有高強度電子供體的新型聚醯亞胺9Ph-ODPI、9Ph-DSPI及9Ph-PMPI並與9Ph-6FPI一起探討記憶體性質。除此之外，3Ph-PIs及5Ph-PIs也加入此章共同討論電子供體對聚醯亞胺記憶體性質的影響。隨著電子供體的強度從3Ph-PIs、5Ph-PIs增加至9Ph-PIs，記憶體的時間有系統性的增長趨勢。為了清楚了解CT complex及記憶時間的關聯性，我們測量記憶體元件在開關時的吸收光譜做為直接證據。我們同時製備具有穩定性的柔軟性記憶體元件做為未來軟性電子材料的應用。第五章節為結論及未來展望。

This study has been separated into five chapters. Chapter 1 is general introduction. In Chapter 2, the new functional triphenylamine-based (TPA-based) aromatic polyether (OXPE) and polyester (6FPET) derived from 4,4’-dihydroxyltriphenyamine with 2,5-bis(4-fluorophenyl)-1,3,4-oxadiazole and 4,4’-(hexafluoroisopropylidene)bis(benzoylchloride), respectively, were prepared and used for memory device application. To understand the relationship between linkage group and memory behavior, polyamide 6FPA, polyimide 6FPI, and the coresponding isomer 6FPI’ were also synthesized and investigated their memory properties. Furthermore, to illustrate the linkage effect systematically, TPA-based sulfonyl-containing polymers DSPE, DSPET, DSPA, and DSPI were also added into discussion. Generally, the TPA-based polymers with flexible linkage, lower LUMO energy level, and higher dipole moment have longer retention time. Chapter 3 describes the memory properties of new functional polyimides 5Ph-ODPI, 5Ph-DSPI, 5Ph-PMPI, and 5Ph-NPPI derived from N,N’-bis(4-aminophenyl)-N,N’-di(4-methoxyl-phenyl)1,4-phenylene-diamine and various dianhydrides. For comparison, the corresponding 5Ph-6FPI was also added into discussion. The differences of HOMO energy levels, LUMOs energy levels, and dipole moment among these five polyimides with different electron-withdrawing acceptor moieties were investigated and demonstrated the effect on the memory behavior. 5Ph-ODPI did not show memory properties, 5Ph-6FPI exhibited dynamic random access memory (DRAM) characteristic, 5Ph-PMPI with stronger electron-withdrawing linkage revealed static random access memory (SRAM) behavior, and 5Ph-NPPI with the strongest electron-withdrawing linkage showed write-once-read-many-times (WORM) type non-volatile memory behavior. On the whole, with the electron-withdrawing moiety intensity of polyimides increasing, the retention time of corresponding memory device increases. However, 5Ph-DSPI has the LUMO energy levels between 5Ph-6FPI and 5Ph-PMPI but revealed non-volatile WORM behavior resulting from the highest dipole moment 5.45D. In chapter 4, the new functional polyimides 9Ph-ODPI, 9Ph-DSPI, and 9Ph-PMPI consisting of electron-donating starburst triarylamine unit and different dianhydrides were synthesized and used for memory device application along with 9Ph-6FPI. To investigate the effects of donor moieties within polyimides on memory behavior, the corresponding 3Ph- series polyimides (3Ph-PIs) and 5Ph- series polyimides (5Ph-PIs) were added into discussion. With the electron-donating intensity increasing from 3Ph-PIs, 5Ph-PIs, to 9Ph-PIs, the retention time of memory device shows the systematical increasing tendency. Besides, the in-situ UV-vis absorption spectra of memory devices during switching-ON were utilized as direct evidence to confirm the relationship between charge transfer (CT) complex stability and memory retention time. Finally, the flexible programmable memory device was fabricated for the practical future flexible electronics applications. Chapter 5 contains conclusions and future works.