Applications of ytterbium in inverted organic photovoltaic cells as high-performance and stable electron transport layers

Abstract

The electron transport layer (ETL) increases the power conversion efficiency (PCE) in organic photovoltaic cells (OPVs) by promoting the formation of ohmic contact between the active layer and the cathode metal.

Micro-Power Generation Characteristics of Thermoelectric Thin Film Devices Processed by Electrodeposition and Flip-Chip Bonding

“…2,8,9 Compared to the in-plane thin film device, the crossplane device is more suitable for a micro-thermoelectric generator because of its low electrical resistance and lack of parasitic heat flow through the substrate. 2,8,9 However, a cross-plane thermoelectric thin film device of vertical configuration has various difficulties from the viewpoint of fabrication processing. 2 Especially, bonding of metal bumps on the upper electrodes in a top substrate to thermoelectric thin film legs in a bottom substrate for circuit formation is difficult enough to limit the realization of a cross-plane thermoelectric thin film device.…”

“…[1][2][3][4][5][6][7][8][9] As a promising energy harvesting method, thermoelectric power generation using a thin film device has drawn much attention because it can be operated with a small temperature difference produced by waste heat or by small heat source, such as body heat, in addition to its advantages of high power density, no moving parts, long lifetime, and high reliability. [1][2][3][4][5][6][7][8][9] A thermoelectric thin film device can be classified as having either an in-plane or cross-plane configuration based on the direction of heat flow through the device. 2,8,9 Compared to the in-plane thin film device, the crossplane device is more suitable for a micro-thermoelectric generator because of its low electrical resistance and lack of parasitic heat flow through the substrate.…”

“…[1][2][3][4][5][6][7][8][9] A thermoelectric thin film device can be classified as having either an in-plane or cross-plane configuration based on the direction of heat flow through the device. 2,8,9 Compared to the in-plane thin film device, the crossplane device is more suitable for a micro-thermoelectric generator because of its low electrical resistance and lack of parasitic heat flow through the substrate. 2,8,9 However, a cross-plane thermoelectric thin film device of vertical configuration has various difficulties from the viewpoint of fabrication processing.…”

“…2 Especially, bonding of metal bumps on the upper electrodes in a top substrate to thermoelectric thin film legs in a bottom substrate for circuit formation is difficult enough to limit the realization of a cross-plane thermoelectric thin film device. [6][7][8][9] In microelectronic packaging, flip-chip technology has been extensively investigated to attach a semiconductor chip directly to a printed circuit board, a flexible substrate, and a glass substrate of a liquidcrystal display panel with various advantages such as small and thin package size as well as high density and fine pitch interconnection. 10,11 Flip-chip technology has a strong potential to be utilized for the fabrication of a thermoelectric thin film device of cross-plane configuration.…”

Reduction of the dark current in a P3HT-based organic photodiode with a ytterbium-fluoride buffer layer for electron transport

“…Of these, LiF/Al composite cathodes are known for their superior electron injection and high electroluminescence in organic light emitting diodes (OLED), and for their reduced dark current density and high detectivity in OPDs [6,12,13]. In a previous study, we demonstrated the properties of ytterbium (Yb) with low work functions as an ETL in organic photovoltaic (OPV) devices and compared its performance to that of LiF [14]. In the OPV, the use of LiF as ETL was shown to have a poor performance and surface characteristics, including high series resistance and low shunt resistance [15,16].…”