A novel surface-type nonvolatile electric memory elements based on organic semiconductors CuPc and H2Pc are fabricated by vacuum deposition of the CuPc and H2Pc films on preliminary deposited metallic （Ag and Cu） el...A novel surface-type nonvolatile electric memory elements based on organic semiconductors CuPc and H2Pc are fabricated by vacuum deposition of the CuPc and H2Pc films on preliminary deposited metallic （Ag and Cu） electrodes. The gap between Ag and Cu electrodes is 3040μm. For the current-voltage （I-V） characteristics the memory effect, switching effect, and negative differential resistance regions are observed. The switching mechanism is attributed to the electric-field-induced charge transfer. As a result the device switches from a low to a high-conductivity state and then back to a low conductivity state if the opposite polarity voltage is applied. The ratio of resistance at the high resistance state to that at the low resistance state is equal to 120-150. Under the switching condition, the electric current increases -- 80-100 times. A comparison between the forward and reverse I-V characteristics shows the presence of rectifying behavior.展开更多
The optoelectronic properties of heterojunction thin film devices with ITO/CuPc/C_（60）/Al structure have been investigated by analyzing their current-voltage characteristics,optical absorption and photocurrent.In th...The optoelectronic properties of heterojunction thin film devices with ITO/CuPc/C_（60）/Al structure have been investigated by analyzing their current-voltage characteristics,optical absorption and photocurrent.In this organic photovoltaic device,CuPc acts as an optically active layer,C_（60） as an electron-transporting layer and ITO and Al as electrodes.It is observed that,under illumination,excitons are formed,which subsequently drift towards the interface with C_（60）,where an internal electric field is present.The excitons that reach the interface are subsequently dissociated into free charge carriers due to the electric field present at the interface.The experimental results show that in this device the total current density is a function of injected carriers at the electrode-organic semiconductor surface,the leakage current through the organic layer and collected photogenerated current that results from the effective dissociation of excitons.展开更多
基金supported by the GIK Institute of Engineering Science and Technology,Pakistan and Physical Technical Institute of Academy of Sciences of Tajikistan
文摘A novel surface-type nonvolatile electric memory elements based on organic semiconductors CuPc and H2Pc are fabricated by vacuum deposition of the CuPc and H2Pc films on preliminary deposited metallic （Ag and Cu） electrodes. The gap between Ag and Cu electrodes is 3040μm. For the current-voltage （I-V） characteristics the memory effect, switching effect, and negative differential resistance regions are observed. The switching mechanism is attributed to the electric-field-induced charge transfer. As a result the device switches from a low to a high-conductivity state and then back to a low conductivity state if the opposite polarity voltage is applied. The ratio of resistance at the high resistance state to that at the low resistance state is equal to 120-150. Under the switching condition, the electric current increases -- 80-100 times. A comparison between the forward and reverse I-V characteristics shows the presence of rectifying behavior.
基金the Ghulam Ishaq Khan Institute of Engineering Sciences and Technology for supporting this work.
文摘The optoelectronic properties of heterojunction thin film devices with ITO/CuPc/C_（60）/Al structure have been investigated by analyzing their current-voltage characteristics,optical absorption and photocurrent.In this organic photovoltaic device,CuPc acts as an optically active layer,C_（60） as an electron-transporting layer and ITO and Al as electrodes.It is observed that,under illumination,excitons are formed,which subsequently drift towards the interface with C_（60）,where an internal electric field is present.The excitons that reach the interface are subsequently dissociated into free charge carriers due to the electric field present at the interface.The experimental results show that in this device the total current density is a function of injected carriers at the electrode-organic semiconductor surface,the leakage current through the organic layer and collected photogenerated current that results from the effective dissociation of excitons.
