A semiconductor process is provided. First, a metal layer, a dielectric layer and a patterned hard mask layer are sequentially formed on a substrate. Thereafter, a portion of the dielectric layer is removed to form an opening exposing the metal layer. Afterwards, a cleaning solution is used to clean the opening. The cleaning solution includes a triazole compound with a content of 0.00275 to 3 wt %, sulfuric acid with a content of 1 to 10 wt %, hydrofluoric acid with a content of 1 to 200 ppm and water. The semiconductor process can reduce the possibility of having an incomplete turning on, a leakage or a short, so that the yield of the product is increased.