Germanium nitride reactions

Most nitride and oxynitride films are deposited at substrate temperatures much higher than 500°C. The formation reactions take place generally only between 900°C and 2500°C. Under such conditions, coating of glass is impossible. There are some exceptions, however, where it is possible to develop low temperature reactions. Thus, for instance, amorphous germanium nitride Ge3N4 has been deposited by ammonolysis of GeCl4 at substrate temperatures between 400 and 600°C [143]. Such films can be used in electronics [144]. 

Ignition or explosive reaction with metals (e.g., aluminum, antimony powder, bismuth powder, brass, calcium powder, copper, germanium, iron, manganese, potassium, tin, vanadium powder). Reaction with some metals requires moist CI2 or heat. Ignites with diethyl zinc (on contact), polyisobutylene (at 130°), metal acetylides, metal carbides, metal hydrides (e.g., potassium hydride, sodium hydride, copper hydride), metal phosphides (e.g., copper(II) phosphide), methane + oxygen, hydrazine, hydroxylamine, calcium nitride, nonmetals (e.g., boron, active carbon, silicon, phosphoms), nonmetal hydrides (e.g., arsine, phosphine, silane), steel (above 200° or as low as 50° when impurities are present), sulfides (e.g., arsenic disulfide, boron trisulfide, mercuric sulfide), trialkyl boranes. 

Of more synthetic interest is the Cs-X catalyzed liquid phase condensation of benzaldehyde with active methylene compounds such as ethyl cyanoacetate, ethyl malonate and ethyl acetoacetate but the yields in these reactions were only in the 40%-70% region. Higher yields were obtained using a germanium substituted faujasite 2 06 or a nitrided aluminophosphate as the basic catalyst. 

The reactions of germanium with oxygen and with nitrogen are reviewed. Particular emphasis has been placed on the relationship between the structure and electronic properties of the oxide and nitride films formed on single crystal germanium surfaces under different processing conditions. A summary of the electronic properties reported is presented and some conclusions are offered based on the recent literature. 

The preparation of Ge3N4 by direct thermal reaction of germanium with NH3 was reported in 1930 by Johnson (115). Germanium powder and ammonia were reacted at 700°C to form the nitride according to the equation ... 

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