1:30 PM - 3:30 PM [16p-P7-4] Studies of Degradation Mechanism of Organic Electroluminescent Devices using Time-of-Flight Secondary Ion Mass Spectroscopy and X-ray Photoelectron Spectroscopy combined with Argon Gas Cluster Ion Beam Etching 〇Shuji Matsuo1, Ako Miisho1, Yoshihiro Yokota1 (1.Kobelco Res. Inst.)