Pin junction

The other way to produce EL devices is based on a pin junction [47]. A pin junction with conjugated polymers was realized by electrochemical doping of the... 

One idea to realize a pin junction with conjugated polymers is to create it in situ by electrochemical doping. By using the conjugated polymer in a solid slate electrochemical cell, the production of bipolar light-emitting pin junction devices can be realized [69, 70]. 

The interfaces between a semiconductor and another semiconductor (e.g. the very important pin junction, the interface between p- and ft-type semiconductors), between a semiconductor and a metal (the Schottky barrier) and between a semiconductor and an electrolyte are the subject of solid-state physics, using a nomenclature different from electrochemical terminology. 

The term photovoltaic effect is further used to denote non-electrochemical photoprocesses in solid-state metal/semiconductor interfaces (Schottky barrier contacts) and semiconductor/semiconductor pin) junctions. Analogously, the term photogalvanic effect is used more generally to denote any photoexcitation of the d.c. current in a material (e.g. in solid ferroelectrics). Although confusion is not usual, electrochemical reactions initiated by light absorption in electrolyte solutions should be termed electrochemical photogalvanic effect , and reactions at photoexcited semiconductor electodes electrochemical photovoltaic effect . 

As shown in Fig. 7.10A, the PLEC was fabricated with a simple sandwiched structure of ITO/polymer/Al. The active layer contained an alkoxyphenyl substituted poly(l,4-phenylene vinylene) (AP-PPV), trimethylolpropane trimethacrylate (TMPTMA), and lithium trifluoromethane sulfonate (LiTf). When a bias voltage was initially applied, the PIN junction was formed by electrochemical doping (Fig. 7.1 OB). At the same time, the ionic conduction channels would be cut off due to the polymerizing of small molecules... 

Gao, J., Yu, G., Heeger, A.J., 1997. Polymer light-emitting electrochemical cells with frozen pin junction. Appl. Phys. Lett. 71,1293-1295. 

Yu, Z., Li, L., Gao, H., Pei, Q, 2013. Polymer light-emitting electrochemical ceUs recent developments to stabilize the pin junction and explore novel device appUcations. Sci. China Chem. 56,1075-1086. 

A. Imamoglu, Y. Yamamoto, Noise suppression in semiconductor pin junctions transition from macroscopic squeezing to mesoscopic Coulomb blockade of electron emission processes. Phys. Rev. Lett. 70(21), 3327 (1993)... 

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