الفهرس | Only 14 pages are availabe for public view |
Abstract The purpose of this thesis is to design and fabricate heterojunction and homojunction light emitting diode (LED). In this LED, inorganic materials are used as n-type (ZnO, CdS, and Cu2O) while conjugated polymers and Cu2O as (p-type). The first task was synthesis vertical alignment of ZnO nanorods on conducting glass substrate using aqueous chemical growth and hydrothermal methods at a low temperature. We employ a common method of successive ionic layer adsorption and reaction (SILAR) in some tasks to deposit CdS as n- type on ZnO NRs and characterized by XRD, SEM, UV and PL techniques. The second task was to find out p- type from organic or inorganic materials that gives high emission. We used conjugated polymer Benzothiadiazole-9, 9’-diethylhexylflurorene Copolymer (P1) and Benzothiadiazole- Hexylthiophene- Hexylphenothiazine- Hexylthiophene Copolymer (P2) as p-type with n-ZnO to fabricate LEDs, and used (poly(3-hexyl-thiophene) (P3HT)) as p-type with n-ZnO-CdS (at different cycles deposited of CdS on ZnO surface) to fabricate LEDs. Cuprous oxide (Cu2O) which synthesis with electrodeposition technique was used as p-type at different bath pH (9, 10, 11, 12, and 13) at constant applied potential of -0.4V (vs. Ag/AgCl) with n-ZnO to fabricate LEDs, also synthesised n-Cu2O at different bath pH (5.2, 5.4, 5.8, 6, and 6.2) at constant applied potential of -0.1V (vs. Ag/AgCl). p-Cu2O and n-Cu2O samples was characterized by XRD, SEM, UV, Raman Spectroscopy and PL techniques. LEDs devices characterized by Electroluminescence (EL) technique and I-V characteristic curve studies by using a multiple source-measure units (SMUs) (2400 SourceMeter® SMU Instruments). |