ORGANIC LIGHT-EMITTING DIODE (OLED) DISPLAY PANEL, ELECTRONIC DEVICE AND MANUFACTURING METHOD
The present disclosure provides an OLED display panel, an electronic device, and a manufacturing method. The OLED display panel comprises a first electrode, a light-emitting layer, a first function layer, and a second electrode. The first function layer includes at least a first-type blocking layer disposed adjacent to the light-emitting layer. A first guest material is doped into a host material of the first-type blocking layer, and a ratio of a second-type carrier mobility of the host material over a second-type carrier mobility of the first guest material is greater than or equal to about 10. The first-type is a hole-type and the second-type is an electron-type.
1 . An OLED display panel, comprising:
a first electrode;
a light-emitting layer, the light-emitting layer including a host material of the light-emitting layer and a guest material of the light-emitting layer;
a first function layer including at least a first-type blocking layer disposed adjacent to the light-emitting layer, wherein a first guest material is doped into a host material of the first-type blocking layer, and a ratio of a second-type carrier mobility of the host material over a second-type carrier mobility of the first guest material is greater than or equal to about 10; and
a second electrode,
wherein the first-type is a hole-type and the second-type is an electron-type, and
T B >T C and T A >T C , such that triplet state excitons of the light-emitting layer is prevented from being transmitted through the first-type blocking layer, where T B is a triplet state energy level of a host material of the first-type blocking layer, T C is a triplet state energy level of a host material of the light-emitting layer, T A is a triplet state energy level of a first guest material of the first-type blocking layer.
2 . The OLED display panel according to claim 1 , wherein:
the first electrode is an anode;
the second electrode is a cathode;
HOMO B −HOMO C ≥0.3 eV; and
HOMO A −HOMO C ≥0.3 eV, where HOMO B is a highest occupied molecular orbital energy level of the host material B of the first-type blocking layer, HOMO C is a highest occupied molecular orbital energy level of the host material C of the light-emitting layer, and HOMO A is a highest occupied molecular orbital energy level of the first guest material A of the first-type blocking layer.
3 . The OLED display panel according to claim 1 , further including:
a second function layer disposed between the first electrode and the light-emitting layer,
wherein the second function layer includes at least a second-type blocking layer, disposed adjacent to the light-emitting layer;
a second guest material is doped in a host material of the second-type blocking layer; and
a ratio of a first-type carrier mobility of the host material in the second-type blocking layer over a first-type carrier mobility of the second guest material in the second-type blocking layer is greater than or equal to about 10.
4 . The OLED display panel according to claim 2 , wherein:
the host material B in the first-type blocking layer includes 4,4-bis(9-carbazolyl)-1,1′-biphenyl (BCP), and
the first guest material A in the first-type blocking layer includes 2-(4-biphenyl)-5-phenyl oxadiazole (PBD).
5 . The OLED display panel according to claim 1 , wherein:
a content of the host material in the first-type blocking material is greater than or equal to about 90%.
6 . The OLED display panel according to claim 1 , wherein:
the second-type carrier mobility of the host material in the first-type blocking layer is configured to be greater than or equal to about 10 −4 cm −2 /V·S, and less than or equal to 10 −3 cm −2 /V·S; and
the second-type carrier mobility of the first guest material in the first-type blocking layer is configured to be less than or equal to about 10 −4 cm −2 /V·S.
7 . The OLED display panel according to claim 3 , wherein:
the first-type carrier mobility of the host material in the second-type blocking layer is configured to be greater than or equal to about 10 −4 cm −2 /V·S, and less than or equal to 10 −3 cm −2 /V·S; and
the first-type carrier mobility of the second guest material in the second-type blocking layer is configured to be less than or equal to about 10 −4 cm −2 /V·S.
8 . The OLED display panel according to claim 1 , wherein:
the first-type blocking layer has a thickness approximately between 1 nm and 20 nm; and
the first function layer further includes at least one of a second-type injection layer, and a second-type transport layer.
9 . The OLED display panel according to claim 3 , wherein:
the second function layer further includes at least one of a second-type injection layer, and a second-type transport layer.
10 . The OLED display panel according to claim 1 , further including a plurality of pixel regions emitting light in different colors, wherein:
the light-emitting layer corresponding to a pixel region emitting red or green light is made of a phosphorescent material; and
the light-emitting layer corresponding to a pixel region emitting blue light is made of a fluorescent material.
11 . The OLED display panel according to claim 1 , further including a plurality of pixel regions emitting light in different colors, wherein:
the light-emitting layer corresponding to a pixel region emitting red or blue light is made of one or two types of host materials; and
the light-emitting layer corresponding to a pixel region emitting green light is made of at least two materials.
12 . The OLED display panel according to claim 1 , further including a plurality of pixel regions emitting light in different colors, wherein:
a micro-cavity structure is formed between the first electrode and the second electrode in a pixel region;
a cavity length of the micro-cavity structure corresponding to the pixel region is positively correlated with a wavelength of emitted light corresponding to the pixel region; and
the cavity length of the micro-cavity structure is a distance between the first electrode and the second electrode.
13 . An electronic device, comprising the OLED display panel according to claim 1 .
14 . A manufacturing method for the OLED display panel, comprising:
sequentially forming a first electrode, a light-emitting layer, a first function layer, and a second electrode, the light-emitting layer including a host material of the light-emitting layer and a guest material of the light-emitting layer; or
sequentially forming a second electrode, a first function layer, a light-emitting layer, and a first electrode, wherein:
the first function layer includes at least a first-type blocking layer disposed adjacent to the light-emitting layer, a first guest material is doped into a host material of the first function layer, and a ratio of a second-type carrier mobility of the host material over a second-type carrier mobility of the first guest material is greater than or equal to about 10;
the first-type is a hole-type and the second-type is an electron-type, and
T B >T C and T A >T C , such that triplet state excitons of the light-emitting layer is prevented from being transmitted through the first-type blocking layer, where T B is a triplet state energy level of a host material of the first-type blocking layer, T C is a triplet state energy level of a host material of the light-emitting layer, T A is a triplet state energy level of a first guest material of the first-type blocking layer.
15 . The manufacturing method for the OLED display panel according to claim 14 , wherein:
the first electrode is an anode;
the second electrode is a cathode;
HOMO B −HOMO C ≥0.3 eV; and
HOMO A −HOMO C ≥0.3 eV, where HOMO B is a highest occupied molecular orbital energy level of the host material B of the first-type blocking layer, HOMO C is a highest occupied molecular orbital energy level of the host material C of the light-emitting layer, and HOMO A is a highest occupied molecular orbital energy level of the first guest material A of the first-type blocking layer.
16 . The manufacturing method for the OLED display panel according to claim 14 , wherein after forming the first electrode and before forming the light-emitting layer, or after forming the light-emitting layer and before forming the first electrode, the manufacturing method further includes forming a second function layer, wherein:
the second function layer includes at least a second-type blocking layer, configured adjacent to the light-emitting layer;
a second guest material is doped in a host material of the second-type blocking layer; and
a ratio of a first-type carrier mobility of the host material in the second-type blocking layer over a first-type carrier mobility of the second guest material in the second-type blocking layer is greater than or equal to about 10.
17 . The OLED display panel according to claim 1 , wherein:
the host material of the light-emitting layer 1,4-bis(5-p-tert-butylphenyl-1,3,4-oxadiazolyl-2)benzene (OXD-7).