Abstract: Systems and techniques for depositing organic material on a substrate are provided, in which one or more shield gas flows prevents contamination of the substrate by the chamber ambient. Thus, multiple layers of the same or different materials may be deposited in a single deposition chamber, without the need for movement between different deposition chambers, and with reduced chance of cross-contamination between layers.

Abstract: According to one embodiment, a compound comprising a ligand LA of Formula I is described. In the structure of Formula I, A1 through A8 are independently carbon or nitrogen, with at least one being nitrogen; X1 is selected from the group consisting of O, S, and Se; X2 and X3 are independently selected from the group consisting of C, N, O, P, and S; ring A is a 5- or 6-membered heterocyclic ring bonded to ring B through a X2—C bond and bonded to M through a metal-carbene bond; any adjacent substitutions in R1 and R2 are optionally linked together to form a ring; the ligand LA is coordinated to a metal M; and the ligand LA is optionally linked with other ligands to comprise up to a hexadentate ligand. Formulations and devices, such as an OLEDs, that include the compound comprising ligand LA of formula I are also described.

Abstract: According to one embodiment, a compound comprising a ligand LA of Formula I is described. In the structure of Formula I, A1 through A8 are independently carbon or nitrogen, with at least one being nitrogen; X1 is selected from the group consisting of O, S, and Se; X2 and X3 are independently selected from the group consisting of C, N, O, P, and S; ring A is a 5- or 6-membered heterocyclic ring bonded to ring B through a X2—C bond and bonded to M through a metal-carbene bond; any adjacent substitutions in R1 and R2 are optionally linked together to form a ring; the ligand LA is coordinated to a metal M; and the ligand LA is optionally linked with other ligands to comprise up to a hexadentate ligand. Formulations and devices, such as an OLEDs, that include the compound comprising ligand LA of formula I are also described.