What are the disadvantages of organic semiconductor compare to silicon germanium?

Answer 1

Organic semiconductors have advantages over inorganic semiconductors in a few areas. First, conductive polymer devices can be fabricated at room temperatures and conditions and can be literally "printed" to make a circuit. Fabrication processes differences also make it possible to make complex organic polymer displays more easily than equivalent inorganic displays. This is convenient to make (e.g.) visual displays. They are also useful in energy-storage application. Their main draw-backs are first, that organic polymer electronic devices tend to be much slower than silicon devices. Further, organic light-emiting diodes tend to have limited life spans (2000 hours or so). So their main uses are for phone and car radio displays, where the device will likely be replaced before it reaches the limit of its life.

Answer 2

Organic semiconductors generally have lower charge carrier mobilities and thermal stability compared to silicon germanium. They also typically have lower production yields and can be more prone to degradation over time.