Flexible polymer substrate

Hanket, G. et al. 2002. "Pilot-scale Manufacture of Cu(lnGa)Se2 Films on a Flexible Polymer Substrate", In Proceedings of the 29th IEEE... 

Solar cells can directly convert solar energy into electricity, which is clean and inexhaustible. Generally, the solar cells are built with a planar sandwiched structure on the rigid substrate, which restricts their applications in many fields. Flexible polymer substrates, such as poly(ethyleneterephthalate) (PET), poly(ethylenenaphthalate) (PEN), and polydimeth-ylsiloxane (PDMS), have been widely used to fabricate flexible solar cells. With high stability and flexibility, the solar cells can easily integrate with other portable or wearable devices to significantly extend their applications. 

Flexible electrochromic devices (ECDs) are becoming increasing important for their promising applications in many areas, such as the portable and wearable electronic devices, including smart windows, functional supercapacitors, and flexible displays. Typically, an ECD consists of four parts of substrate, conductive electrode, electrochromic material, and electrolyte. Enormous efforts have been made to improve the flexibility of ECDs including utilizing flexible polymer substrates and conductive materials. 

Also Kinkeldei et al. (2012) produced an electronic nose that consisted of four carbon black/polymer sensors fabricated on a flexible polymer substrate, which were cut into yam-like strips and integrated into a textile stmcture. 

Fabrication of high aspect ratio Si structures onto flexible polymer substrate. The intent is to fabricate planar Si structures first and transfer them onto a polymer substrate (a) so that they can lie on a curvilinear surface (b). (Source Zeng, X. and pang H. 2011. Journal of Microelectromechanical Systems, 20(1), 6-8. With permission.)... 

The aforementioned embroidered textiles were integrated on a low-loss and highly flexible polymer substrate. We employed PDMS as our substrate due to its mechanical flexibility and stretchability, inherent chemical stability, and water resistance (Koulouridis et al., 2006). As demonstrated in Wang et al. (2012b), the resultant PDMS composite had a dielectric constant of er = 3.0 and a low-loss tangent of tan < 0.02. Another advantage of PDMS is that its permittivity can be increased from 8r = 3.0-13.0 by dispersing ceramic powder into the PDMS matrix (Koulouridis et al., 2006). 

Monarch Antenna Inc. developed a wearable antenna for soldiers using a flexible substrate worn under a vest. The antenna operates in the unlicensed ISM band of 2.4-2.48 GHz and is currently being redesigned to print on a flexible polymer substrate. Moreover, they collaborated with NASA for developing a multi-beam adaptive wearable antenna for astronauts based on Monarch s patented SS A technology (Monarch Antenna Inc., 2015). 

This current limitation is the most serious drawback of flexible TF batteries. Therefore, to achieve high current densities, it is necessary to heat-treat the cathode at temperatures higher than 700°C. This shortcoming tends to prevent the use of flexible polymer substrates for cathode films in some specific applications. The internal resistance of such batteries is dependent on the polyimide sheet thickness and the annealing temperature, which must not exceed 400 C. If the battery is made on a rigid ceramic substrate with a cathode of comparable thickness, annealing temperatures as high as 750°C can be used. 

In terms of cost and manufacturing technologies for scalable devices, because the functional materials of OPVs are likely to dissolve in common organic solvents, they can be easily printed or coated onto the flexible polymer substrates such as polyethylene terephthalate (PET) and polyethylene... 

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