Inorganic chemicals in electronics

Most people associate electronic devices with silicon chips, and indeed the key component of digital electronics is the silicon integrated circuit. It is interesting to note that in a similar manner to the way the heavy inorganic sector is associated with certain geographical locations, the microelectronics industry also has certain focal points. We frequently hear about Silicon Valley in California and Silicon Fen near Cambridge, UK. One reason for the growth of microelectronics in these areas is the proximity to universities and academic input into research and development. 

Titanium dioxide is the most commonly used white pigment in paints. It is also used as a sunblock, preventing harmful UV radiation from reaching the skin and reflecting visible light. 

Silicon that contains donor impurities is known as n-type silicon, while silicon doped with acceptor impurities is known as p-type. Many semiconducting devices consist of a layer of p-type silicon on top of a layer of n-type silicon — the so-called p-n junction. An electric current can flow in only one direction across this junction. The extra electrons in the n-type silicon can move across into the p-type material, but electrons will not flow the other way, as the n-type material already has an excess of electrons. 

Doping at these minute levels means that unwanted impurities in the host semiconductor must be reduced to very low levels 99.999 9 to 99.999 999% pure materials are often required. 

Silicon is obtained by the reduction of silicon dioxide with coke in an electric arc furnace  

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