Optoelectronic organic inorganic semiconductor heterojunctions The book summarizes advances in development of organic inorganic semiconductor heterojunctions challenges and possible solutions for material device design and prospects for commercial applications. It introduces the concept and basic mechanism of semiconductor heterojunctions. It describes a series of organic inorganic semiconductor heterojunctions with desirable electrical and optical properties for optoelectronic devices. Typical devices such as solar cells photo detectors and optoelectronic memories are discussed. Materials device challenges and strategies are discussed to promote the commercial translation of semiconductor heterojunction based optoelectronic devices.