Tetramethylsilane is the chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 Si(CH₃)₄. It is the simplest tetraorganosilane. Like all silanes

Silanes

Silanes are chemical compounds of silicon and hydrogen, which are analogues of alkane hydrocarbons. Silanes consist of a chain of silicon atoms covalently bonded to each other and to hydrogen atoms. The general formula of a silane is SinH2n+2...

, the TMS framework is tetrahedral. TMS is a building block in organometallic chemistry

Organometallic chemistry

Organometallic chemistry is the study of chemical compounds containing bonds between carbon and a metal. Since many compounds without such bonds are chemically similar, an alternative may be compounds containing metal-element bonds of a largely covalent character...

 but also finds use in diverse niche applications.
TMS is a by-product of the production of methyl chlorosilanes, SiCl_x(CH₃)_4−x, via the direct process

Direct process

The Direct Process, also called the Direct Synthesis, Rochow Process, and Müller-Rochow Process is the most common technology for preparing organosilicon compounds on an industrial scale. It was first reported independently by Eugene G. Rochow and Richard Müller in the 1940s...

 of reacting methyl chloride with silicon.