The present article describes the elaboration of a microactuator based on the decomposition of an energetic material. The fabrication of such a pyrotechnic actuator relies on novel smart materials and a simplified process developed through chemistry. The heterometallic Werner complex [Co(NH3)6]2[Mn(NO3)4]3 was chosen as an energetic material releasing only biocompatible gases when ignited. It was deposited on a resistance at the bottom of a micrometer scale chamber comprising directly photocurable polydimethylsiloxane walls and a thin elastic membrane as a roof. The membrane also comprised polysiloxanes. One of the key steps consisted of the grafting of siloxane-bearing acrylate moieties onto a standard silicon wafer, similar to those incorporated on the polysiloxane. The grafting was successfully characterized by XPS. Moreover, the walls of the cavity were elaborated by direct photolithography. After deposition of the energetic material, the cavity was sealed thanks to membrane grafting and the process was optimized to afford strong wafer/wall and wall/membrane interfaces in order to withstand the high mechanical stress imposed on the device in use.