Layered architectures advantage

Other device architectures include inverted OLEDs. Here the cathode is in intimate contact with the substrate. The organic layers are then deposited onto the cathode in reverse order, i.e., starting with the electron transport material and ending with the HIL. The device is completed with an anode contact. In this case, as above, one of the electrodes is transparent, and light exits from the device through that contact. For example, Bulovic et al. [38], fabricated a device in which Mg/Ag was the bottom contact and ITO the top electrode. The advantage of this type of architecture is that it allows for easier integration with n-type TFTs (see Section 7.5 for a discussion of active-matrix drive OLED displays). 

In the top-gate architecture, the semiconductor is deposited before the gate dielectric and the gate electrode. This has several advantages. First, since the semiconductor is deposited on a known surface (the substrate itself, in typical examples), it is possible to exploit the fact that this substrate is typically extremely smooth and of known chemistry to ensure that the quality of the printed semiconductor is maximized. Most current in a transistor flows very close to the semiconductor-dielectric interface. In a top-gated transistor, therefore, this current flows near the top interface of the semiconductor this may then be optimized to maximize the quality of the same. Additionally, since this layer is covered by the dielectric and gate, it may be protected from damage from subsequent process steps, etc. 

As a consequence of this unacceptable situation, the interest in model systems suitable for the construction and study of complex lipid/protein membrane architectures increased steadily over the years [7], The classical portfolio of model membranes used for biophysical and interfacial studies of lipid (bi)layers and lipid/protein composites includes Langmuir monolayers assembled at the water/air interface, (uni- and multi-lamellar) vesicles in a bulk (liposomal) dispersion, the bi-molecular lipid membrane (BLMs), and various types of solid supported membranes [8], All these have their specific advantages but also suffer from serious drawbacks. 

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