Abstract: Organic optoelectronic devices, such as a modulator (54) and a photodetector (73) comprising alternating layers (58) of two crystalline planar organic aromatic semiconductors (60 and 62), have been grown by organic molecular beam deposition. These organic substances have been deposited in ultra-thin layers only 10 .ANG. in depth using organic molecular beam deposition methods. Due to the anisotropic character of these organic materials,, the devices formed using these methods possess unique electronic and optical properties. The preferred embodiment of the invention utilizes 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and 3,4,7,8-naphthalenetetracarboxylic dianhydride (NTCDA). While the inventors have identified PTCDA and NTCDA as excellent materials for the manufacture of organic optoelectronic IC devices, the broad scope of the present invention encompasses the use of any planar organic aromatic semiconductor which readily forms a crystalline structure.

Abstract: Certain crystalline organic semiconductor compounds, such as 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), when deposited by an ultrahigh vacuum process of organic molecular beam deposition, form highly ordered "quasi-epitaxial" films (32). Due to asymmetries in the molecular crystal structure of such compounds, the ordering of the films results in giant asymmetries in their dielectric properties. Such large dielectric asymmetries permit the construction of a variety of devices, including optical isolators (38), optically isolated lasers (48), optical isolated optical amplifiers (64), polarization-selective photodiodes (76), and metal-organic-inorganic semiconductor-metal detectors, among others.