THATTHE TOUT UNTUK USU 20180134954A1ROMAW ATU TO NIKALI HINTHI ( 19) United States (12 ) Patent Application Publication ( 10) Pub . No. : US 2018 /0134954 A1 TSAI et al. (43 ) Pub . Date : May 17 , 2018 ( 54 ) ORGANIC ELECTROLUMINESCENT Related U . S . Application Data MATERIALS AND DEVICES (63 ) Continuation - in -part of application No . 15 /407 ,337 , (71 ) Applicant : Universal Display Corporation , filed on Jan . 17 , 2017 . Ewing , NJ (US ) (60 ) Provisional application No .62 / 293 ,100 , filed on Feb . 9 , 2016 , provisional application No. 62 / 338 ,616 , filed (72 ) Inventors : Jui- Yi TSAI, Newtown, PA (US ) ; on May 19 , 2016 . Chuanjun XIA , Lawrenceville , NJ (US ) ; Chun LIN , Yardley, PA (US ) ; Publication Classification Adrian U . PALACIOS , Zaragoza (ES ) ; (51 ) Int. CI. Enrique OÑATE , Zaragoza (ES ) ; CO9K 11 /06 (2006 .01 ) Miguel A . Esteruelas , Zaragoza (ES ) ; CO7F 15 / 00 ( 2006 . 01 ) Pierre -Luc T . BOUDREAULT , HOIL 51/ 00 (2006 .01 ) Pennington , NJ (US ); Sonia BAJO , 2 ) U . S . CI. Zaragoza (ES ) ; Montserrat OLIVÁN , CPC . C09K 11 /06 ( 2013 . 01 ) ; HOIL 51 /5016 Zaragoza (ES ) (2013 . 01 ) ; HOIL 51/ 0085 ( 2013 .01 ) ; CO7F ( 73 ) Assignee : Universal Display Corporation , 15/ 0033 (2013 . 01 ) Ewing , NJ (US ) (57 ) ABSTRACT Novel Iridium complexes having three different bidentate ( 21 ) Appl. No .: 15 / 866 , 561 ligands useful for phosphorescent emitters in OLEDs are disclosed . At least one of the three different bidentate ligands (22 ) Filed : Jan . 10 , 2018 is a carbene ligand . ) www Patent Application Publication May 17, 2018 Sheet lof7 US 2018 / 0134954 A1 ** “ ? ,,, MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM M MMMM * * * mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm &s??????8 … … … … … * * . ) Ht - ? FIG ? 1 Patent Application Publication May 17 , 2018 Sheet 2 of 7 US 2018 / 0134954 A1 ????? ????? ????? ????? ??? ?????? ???????? ????? ????? ???????? ????? ????? ?????? ??? ?? ????? ????? ????? ????? ???? ????? ???? ?? ? FIG . 2 Patent Application Publication May 17 , 2018 Sheet 3 of 7 US 2018 / 0134954 A1 De 0 ( 0) (15 ) FIG . 3 Patent Application Publication May 17 , 2018 Sheet 4 of 7 US 2018 / 0134954 A1 ** YN( 3 ) 0( 1 ) ** * * ** ** * * * * ** i misto *** * * * to *** FIG . 4 Patent Application Publication May 17 , 2018 Sheet 5 of 7 US 2018 / 0134954 A1 402) FIG . 5 Patent Application Publication May 17 , 2018 Sheet 6 of 7 US 2018 / 0134954 A1 N ( 1) C(100 (:1 ) Y CO FIG . 6 Patent Application Publication May 17 , 2018 Sheet 7 of 7 US 2018 / 0134954 A1 FIG . 7 US 2018 /0134954 A1 May 17 , 2018 ORGANIC ELECTROLUMINESCENT MATERIALS AND DEVICES CROSS -REFERENCE TO RELATED APPLICATIONS [ 0001 ] This application is a continuation - in - part applica tion of U . S . patent application Ser. No . 15 / 407, 337 , filed Jan . 17 , 2017 , which claims priority under 35 U . S . C . $ 119 ( e ) ( 1 ) from U . S . Provisional Application Ser . No . 62 /293 , 100 , filed Feb . 9 , 2016 , and U . S . Provisional Application Ser. No . [ 0007 ] In this , and later figures herein , we depict the dative 62 /338 ,616 , filed May 19 , 2016 , the entire contents of which bond from nitrogen to metal (here , Ir ) as a straight line . are incorporated herein by reference . [0008 ] As used herein , the term " organic ” includes poly meric materials as well as small molecule organic materials FIELD that may be used to fabricate organic opto - electronic devices. “ Small molecule ” refers to any organic material that [ 0002 ] The present invention relates to compounds for use is not a polymer, and “ small molecules ” may actually be as phosphorescent emitters , and devices , such as organic quite large . Small molecules may include repeat units in light emitting diodes, including the same. some circumstances . For example , using a long chain alkyl group as a substituent does not remove a molecule from the " small molecule” class . Small molecules may also be incor BACKGROUND porated into polymers , for example as a pendent group on a polymer backbone or as a part of the backbone . Small [ 0003] Opto -electronic devices that make use of organic molecules may also serve as the core moiety of a dendrimer, materials are becoming increasingly desirable for a number which consists of a series of chemical shells built on the core of reasons . Many of the materials used to make such devices moiety . The core moiety of a dendrimer may be a fluorescent are relatively inexpensive , so organic opto - electronic or phosphorescent small molecule emitter. A dendrimer may devices have the potential for cost advantages over inorganic be a “ small molecule , " and it is believed that all dendrimers devices. In addition , the inherent properties of organic currently used in the field of OLEDs are small molecules . materials , such as their flexibility , may make them well [0009 ] As used herein , “ top ” means furthest away from suited for particular applications such as fabrication on a the substrate , while “ bottom ” means closest to the substrate. flexible substrate . Examples of organic opto - electronic Where a first layer is described as “ disposed over” a second devices include organic light emitting diodes/ devices layer, the first layer is disposed further away from substrate . (OLEDs ) , organic phototransistors , organic photovoltaic There may be other layers between the first and second layer, cells , and organic photodetectors . For OLEDs, the organic unless it is specified that the first layer is “ in contact with " materials may have performance advantages over conven the second layer . For example , a cathode may be described tional materials . For example, the wavelength at which an as “ disposed over ” an anode, even though there are various organic emissive layer emits light may generally be readily organic layers in between . tuned with appropriate dopants . [ 0010 ] As used herein , “ solution processible ” means [ 0004 ] OLEDs make use of thin organic films that emit capable of being dissolved , dispersed , or transported in light when voltage is applied across the device . OLEDs are and /or deposited from a liquid medium , either in solution or becoming an increasingly interesting technology for use in suspension form . applications such as flat panel displays , illumination , and [0011 ] A ligand may be referred to as “ photoactive ” when backlighting . Several OLED materials and configurations it is believed that the ligand directly contributes to the are described in U . S . Pat . Nos . 5 , 844 , 363 , 6 ,303 ,238 , and photoactive properties of an emissive material. A ligand may 5 ,707 , 745 , which are incorporated herein by reference in be referred to as “ ancillary ” when it is believed that the their entirety. ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the [0005 ] One application for phosphorescent emissive mol properties of a photoactive ligand . ecules is a full color display . Industry standards for such a [0012 ] As used herein , and as would be generally under display call for pixels adapted to emit particular colors , stood by one skilled in the art, a first “ Highest Occupied referred to as “ saturated ” colors . In particular, these stan Molecular Orbital ” (HOMO ) or “ Lowest Unoccupied dards call for saturated red , green , and blue pixels . Alterna Molecular Orbital” ( LUMO ) energy level is “ greater than ” tively the OLED can be designed to emit white light . In or “ higher than ” a second HOMO or LUMO energy level if conventional liquid crystal displays emission from a white the first energy level is closer to the vacuum energy level . backlight is filtered using absorption filters to produce red , Since ionization potentials ( IP ) are measured as a negative green and blue emission . The same technique can also be energy relative to a vacuum level , a higher HOMO energy used with OLEDs. The white OLED can be either a single level corresponds to an IP having a smaller absolute value EML device or a stack structure . Color may be measured ( an IP that is less negative ) . Similarly , a higher LUMO using CIE coordinates , which are well known to the art . energy level corresponds to an electron affinity (EA ) having [ 0006 ] One example of a green emissive molecule is a smaller absolute value (an EA that is less negative ) . On a tris ( 2 - phenylpyridine ) iridium , denoted Ir (ppy ) 3 , which has conventional energy level diagram , with the vacuum level at the following structure : the top , the LUMO energy level of a material is higher than US 2018 /0134954 A1 May 17 , 2018 the HOMO energy level of the same material . A " higher ” and the ligand Lc is HOMO or LUMO energy level appears closer to the top of such a diagram than a “ lower ” HOMO or LUMO energy level. RY [ 0013 ] As used herein , and as would be generally under stood by one skilled in the art , a first work function is " greater than ” or “ higher than ” a second work function if the first work function has a higher absolute value . Because work functions are generally measured as negative numbers relative to vacuum level, this means that a “ higher” work function is more negative . On a conventional energy level wherein M is a metal having an atomic number greater than diagram , with the vacuum level at the top , a “ higher ” work 40 ; wherein x is 0 , 1 , or 2 ; wherein y is 1 , 2 , or 3 ; wherein function is illustrated as further away from the vacuum level z is 0 , 1 , or 2 ; wherein x + y + z is the oxidation state of the in the downward direction . Thus , the definitions of HOMO metal M ; wherein L , is different from L , and when x , y , or and LUMO energy levels follow a different convention than z is larger than 1 , each plurality of L?, LB , or Lc are also work functions . different ; wherein rings A , B , C , and D are each indepen [0014 ] More details on OLEDs, and the definitions dently a 5 or 6 -membered carbocyclic or heterocyclic ring ; described above , can be found in U . S . Pat. No . 7 ,279 , 704 , wherein R4, RB , RC, and RD each independently represent which is incorporated herein by reference in its entirety .