Organic Photosensitive Devices Comprising a Squaraine Containing Organoheterojunction and Methods of Making Same

Abstract

An organic photosensitive optoelectronic device comprising at least one Donor-Acceptor heterojunction formed from a squaraine compound of formula I:wherein each of Ar1 and Ar2 is independently chosen from an optionally substituted aromatic group. The organic optoelectronic device described herein may also comprise a Donor-Acceptor heterojunction that is formed from at least two different squaraine compounds. A method of making the disclosed device, which may include at least one sublimation step for depositing the squaraine compound, is also disclosed.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is based upon and claims priority to U.S. Provisional Patent Application No. 61 / 097,143, entitled “Organic Photosensitive Devices Comprising a Squaraine Containing Organoheterojunction and Methods of Making Same,” filed Sep. 15, 2008, the entire content of which is incorporated herein by referenceJOINT RESEARCH AGREEMENT[0002]The claimed invention was made by, on behalf of, and / or in connection with the following parties to a joint university-corporation research agreement: The University of Southern California, The Regents of the University of Michigan, and Global Photonic Energy Corporation. The agreement was in effect on and before the date the claimed invention was made, and the claimed invention was made as a result of activities undertaken within the scope of the agreement.BACKGROUND[0003]The present disclosure generally relates to organic photosensitive optoelectronic devices having a squaraine compound as a donor m...

AI Technical Summary

Benefits of technology

[0054]In one embodiment the method of forming an organic photosensitive optoelectronic device comprises depositing CuPc on the substrate prior to depositing the squaraine compound. In another embodiment, the method of forming an organic photosensitive optoelectronic device comprises depositing a layer of an organic compound (e.g., NPD) on the substrate prior to depositing the squaraine compound in order to enhance performance. Without being bound by any theory, it is believed that this organic compound acts to form a better contact between the squaraine and the ITO anode.

Problems solved by technology

A photodetector or photoconductor provides a signal or current to control detection circuitry, or the output of information from the detection circuitry but does not provide power to the circuitry, device or equipment.

However, efficient crystalline-based devices, especially of large surface area, are difficult and expensive to produce due to the problems inherent in producing large crystals without significant efficiency-degrading defects.

On the other hand, high efficiency amorphous silicon devices still suffer from problems with stability.

The maximum total power generated by a PV device is inherently incapable of exceeding the product, ISC×VOC.

Either of these outcomes is undesirable in a photosensitive optoelectronic device.

Such a process can be induced by the built-in electric field, but the efficiency at the electric fields typically found in organic devices (F˜106 V / cm) is low.

However, organic PV devices typically have relatively low external quantum efficiency (electromagnetic radiation to electricity conversion efficiency), being on the order of 1% or less.

In this process energy is lost which will result in a lower efficiency for the device.

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