Multilayer devices

On the experimental front. Burrows and Forrest [155] have measured the electric field and thickness dependence of the current and radiance from bilayer devices with various HTLs and Alq3 as the ETL. The data were analyzed in terms of trap-limited transport in the Alq3 layer, with the assumption that the voltage drop across the H lL is negligible. However, this assumption was challenged by Vestweber and Riess [156] and Giebeler et al. [157], who demonstrated that HTL plays an important role in determining the efficiency of bilayer OLEDs. 

---

Multilayer Devices The Incorporation of Charge-Transporting Layers... 

Refining the Properties of PPV - Multilayer Devices 13 Multilayer Devices The Incorporation of Charge-Transporting Layers 14... 

Jiang and Zhu (2000) and Qiu and Zhu (2001) have reported the fabrication of multilayered devices composed of stacks of compression-molded disks of alternating compositions. One type of disk is either P(SA-EG) or P[SA-co-TMAgly)-Z>-EG] and the other is a pH-sensitive, protein-loaded blend of, for example, poly(methacrylic acid) and polyethoxazoline. The release of model proteins, myoglobin, bovine serum albumin, and FITC-dextran, and compounds such as brilliant blue have been studied and pulsatile release profiles have been demonstrated (Jiang and Zhu, 2000 Qiu and Zhu, 2001). 

MB Wolk, PF Baude, JM Florczak, FB McCormick, and Y Hsu, Thermal Transfer Element for Forming Multilayer Devices, U.S. Patent 6,114,088, 2000. 

EL from tetraalkoxy-substituted PPV 20, synthesized by Gilch polymerization, was recently reported [84], A multilayer device ITO/PEDOT/20/PBD/LiF/Al with PBD as an ETL emits green-yellow light with a luminescent efficiency of 0.121m/W, a maximum brightness of 8200 cd/m2, and a turn-on voltage of 5 V. 

Recently, Jen s group synthesized a series of high Tg fluorinated polymers with a hole transporting TPA group covalently attached as side chains (55) (Scheme 3.21) [99]. This type of polymer can be processed into thin films by simple thermal cyclopolymerization without introducing any by-products [100]. The polymers (56, 57) are insoluble in most organic solvents and can be conveniently streamlined into a multilayer device fabrication process [101,102]. The... 

From optical point of view, an OLED structure can be considered as a multilayer thin-film system composed of absorbing and nonabsorbing materials, as shown in Figure 6.27. Therefore, the optical properties and optimal structure of such a multilayer device can be investigated by applying thin-film optical analysis techniques. Based on the theory of optical admittance analysis for analyzing the optical properties of a thin-film system [92], the optical properties of an OLED thin-film system can be simulated to reduce the ambient reflection. 

The ability to apply a planarizing, optically transparent, thermally stable polymer system that cures under relatively mild conditions has recently been demonstrated to have utility in the fabrication of multilayer devices such as advanced color liquid-crystal display31,32 The ability to apply this material as a dielectric or optical coating for thin-film electronics devices has also recently been demonstrated with the fabrication of an optical wave guiding device.33... 

Adhesive patches may also be monolithic or multilayered devices of the reservoir or matrix type for either systemic or local drug delivery (Fig. 8). The two main manufacturing processes to prepare adhesive patches are solvent casting and direct milling (with or without a solvent). The intermediate product is a sheet from which... 

The main starting point for thin-fihn low molecular weight materials was the work reported by Ching W. Tang and Steven van Slyke of Kodak in 1987, when they described the green electrolnminescence obtained from a thin film of vapour deposited aluminium tris(8-hydroxyquinoline) (Alq). ° Since that time the development of multilayer device structures and several new important classes of organic EL materials has led to snbstantial improvements and to the commercial development of display technologies based on this system. ... 

Myers EB, Ralph DC, Katine JA, Louie RN, Buhrman RA (1999) Current-induced switching of domains in magnetic multilayer devices. Science 285 867-870... 

---