Patent ID: 7540978
Filing Date: 2009-06-02
Classification: C09K,H01L,H05B,Y02E

Abstract:
1. Organic semiconductor material containing a hole transport layer of an organic matrix material doped with an organic dopant by coevaporation characterized in that the organic matrix material comprises at least partly one or more spiro-bifluorene compounds of the formula (I) and/or the formula (II) wherein each R and/or R′ in formula (1) and formula (II) is independently selected from the group consisting of hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, NH 2 , N(CH 4 ) 2 , and NPh 2 , wherein not all R in formula (I) are simultaneously hydrogen and wherein in formula (II) R is not hydrogen, wherein the glass transition temperature of the organic matrix material being at least 120° C. and the highest occupied molecular orbital (HOMO) of the matrix material lying at a maximum energy level of 5.4 eV.