Process and Method of Producing Trisilane
Publication Date: 2004-Oct-11
The IP.com Prior Art Database
Title: PROCESS AND METHOD OF PRODUCING TRISILANE
This invention disclosure concerns a process and method of producing Trisilane (Si3H8). The process involves treating Octachlotrisilane (Si3Cl8), dissolved or suspended within a suitable organic solvent, with a mild reducing agent(s) [e.g., LiAlH4, a mixture of LiH and LiAlH4, NaBH4, or mixtures of LiCl and NaBH4] in solid form or dissolved in (or suspended within) the same, or in another, organic solvent. Control over the reactant concentrations employed during this process, and the rate of mixing between reactants, as well as controlling reaction temperatures, are also important aspects of this process.
Methods of producing Silane and Disilane are relatively well known. There are even many documented references involving the production of Trisilane. However, to date, none of the previously known methods of producing Trisilane are economical because the production yields are typically very low and the separation of co-produced materials (due to unwanted side reactions) is costly.
The object of the present disclosure is to describe a useful, economical, and efficient process and method of producing Trisilane, in relatively pure and high yields, that contains none of the disadvantages of previously disclosed techniques. This method involves dissolving or suspending Octachlotrisilane (Si3Cl8), in a suitable organic solvent [e.g., an organic solvent that is inert with respect to chemical reactions between itself and the dissolved Octachlotrisilane] and then allowing that solution to come in intimate contact with conventional mild reducing agents [e.g., LiAlH4, mixtures of LiH and LiAlH4, NaBH4, and mixtures of LiCl and NaBH4] in solid form or dissolved (or suspended) in the same, or in another, organic solvent.
Examples of suitable organic solvents are relatively high boiling point ethers [e.g., n-Butyl Ether, Diethylene Glycol Dimethyl Ether (Monoglyme), Diethylene Glycol Dimethy Ether (Diglyme), Triethlene Glycol Dimethly Ether (Triglyme), and Tetraethylene Glycol Dimethyl Ether (Tetraglyme)]. The previous list of organic solvents is not meant to specify the only possible choices for suitable organic solvents. There are many other suitable solvent choices well known in this kind of art. However, it is known that certain organic solvents may have advantages over others [e.g., in their ability to dissolve higher concentrations of certain reacting substances or their use may involve less costly methods of purification and re-use over again]. The main point here is to describe a specific process and method of operation that does work well but not exclude the possibility of employing other suitable organic solvents (or reducing agents) that facilitate the production of Trisilane according to the disclosed process and methods. Note: certain types of organic ethers are capable of forming unstable (i.e., explosive) organic peroxides when in contact with air or Oxy...