TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: In the upper region and the lower region of the bulk heterojunction active layer, a mobility of the majority carriers having the same polarity is different. A surface of the active region polarity definition layer has a hydrophobic characteristic and the majority carriers in the lower region of the bulk heterojunction active layer are p-type carriers, or the surface of the active region polarity definition layer has a hydrophilic characteristic and the majority carriers in the lower region of the bulk heterojunction active layer are n-type carriers. The active region polarity definition layer has a thickness of 1-30 nm. The bulk heterojunction active layer consists of a mixture of a donor and an acceptor, where the donor is poly(3-hexylthiophene) (P3HT), poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene), poly(2,1,3-benzothiadiazole-4,7-diyl)(4,4-bis(2-ethyl-hexyl)-4H-cyclopenta(2,1-b:3,4-b')dithiophene-2,6-diyl) (PCPDTBT) or copper phthalocyanine, and the acceptor is (6,6)-phennyl-C61-butyric acid methyl ester (C60-PCBM), (6,6)-phenyl-C71-butyric acid methyl ester (C70-PCBM), perylene, or 3,4,9,10-perylenetetracarboxylic-bis-benzimidazole. The bulk heterojunction active layer consists of a mixture of a donor and an acceptor, where the mixture is a mixture of PCPDTBT and C70-PCBM, a mixture of P3HT and C60-PCBM, or a mixture of P3HT and C70-PCBM. The active region polarity definition layer includes at least two active regions, and a device isolation region is between the active regions, and a polarity slope of the bulk heterojunction active layer on the device isolation region is smaller than a polarity slope of the bulk heterojunction active layer on the active regions. The active region polarity definition layer includes first and second active region polarity definition layers corresponding with first and second active regions of the active region polarity definition layer, where a device isolation region is between the first and second active regions, the first active region polarity definition layer and the second active region polarity definition layer have different surface characteristics, and the majority carriers in the lower region of the bulk heterojunction active layer on the first active region polarity definition layer and the majority carriers in the lower region of the bulk heterojunction active layer on the second active region polarity definition layer have different polarities. The polarity slope of the bulk heterojunction active layer on the device isolation region is smaller than the polarity slope of the bulk heterojunction active layer on the first and second active region polarity definition layers. The organic electronic device further comprises: a lower gate insulating layer configured to contact the lower region of the active region polarity definition layer; a lower gate electrode configured to contact the lower gate insulating layer; an upper gate insulating layer configured to contact the bulk heterojunction active layer; an upper gate electrode configured to contact the upper gate insulating layer; and a source/drain electrode configured to contact one of the lower gate insulating layer and the upper gate insulating layer. The lower and upper gate electrodes are electrically connected. The organic electronic device further comprises: a lower organic field effect transistor including a first polar channel consisting of the lower region of the bulk heterojunction active layer; and an upper organic field effect transistor including a second polar channel consisting of the upper region of the bulk heterojunction active layer. The bulk heterojunction active layer is many bulk heterojunction active layers sequentially stacked. Preferred Method: The step of forming the bulk heterojunction active layer comprises forming a film with a mixture of the donor and acceptor by a solution process, or forming a film with the mixture of donor and acceptor by a solution process. The method, after the forming the film, further comprises: performing a first annealing process at a lower temperature than a lower of glass transition temperatures of each of the donor and the acceptor; and performing a second annealing process at a higher temperature than a lower of the glass transition temperatures of each of the donor and the acceptor, and at a lower temperature than a higher of the glass transition temperatures of each of the donor and the acceptor. Forming the active region polarity definition layer includes: forming at least two active regions in the active region polarity definition layer, and separately patterning the active region polarity definition layer according to the active regions so as to expose a device isolation region; or forming first and second active regions in the active region polarity definition layer, and separately patterning the active region polarity definition layer according to the first and second active regions so as to expose a device isolation region and form first and second active region polarity definition layers corresponding with the first and second active regions, where the first and second active region polarity definition layers have different surface characteristics. Forming the bulk heterojunction active layer includes: forming the bulk heterojunction active layer so that a polarity slope of the bulk heterojunction active layer on the device isolation region is smaller than a polarity slope of the bulk heterojunction active layer on the active regions; or forming the bulk heterojunction active layer so that the majority carriers in the lower region of the bulk hetero junction active layer on the first active region polarity definition layer and the majority carriers in the lower region of the bulk heterojunction active layer on the second active region polarity definition layer have different polarities. The bulk heterojunction active layer is formed so that the polarity slope of the bulk heterojunction active layer on the device isolation region is smaller than the polarity slope of the bulk heterojunction active layer on the first and second active region polarity definition layers. Forming the bulk heterojunction active layer comprises sequentially stacking a first bulk heterojunction active layer and a second bulk heterojunction active layer on the active region polar definition layer.