Orientation of Si phthalocyanine investigated by X-ray absorption spectroscopy and molecular orbital calculation

Sekiguchi, Tetsuhiro  ; Baba, Yuji  ; Shimoyama, Iwao   ; Honda, Mitsunori   ; Hirao, Norie; Narita, Ayumi; Deng, J.*

Metal phthalocyanines (Pc) have attracted growing attention due to potential application as organic semiconductors or light emitters. Recently it has been pointed out that orientation of Pc molecules is one of key properties that improve the career mobility. We studied orientation property of Si-phthalocyanine thin films using synchrotron radiation. We report on following topics: (1) Orientation analysis using polarized X-rays, (2) Effect of metal substrates and annealing on orientation, (3) Analysis aided by molecular orbital method, and (4) New method to observe chemical-bond directions in nanometer scale using combined techniques of polarized X-ray absorption fine structure (XAFS) spectroscopy and photoelectron emission microscopy (PEEM).