二氯硅烷，缩写DCS，是一种无机化合物，化学式为H₂SiCl₂。

二氯硅烷可由硅烷和氯化氢按化学计量比在三氯化铝催化剂的存在下反应制备：

它也可以利用三氯硅烷来制备：

2 SiHCl₃ ⇔ SiCl₄ + SiH₂Cl₂

Dichlorosilane, or DCS as it is commonly known, is a chemical compound with the formula H₂SiCl₂. In its major use, it is mixed with ammonia (NH₃) in LPCVD chambers to grow silicon nitride in semiconductor processing. A higher concentration of DCS:NH₃ (i.e. 16:1), usually results in lower stress nitride films.