Integrated thermal sensor having a housing delimiting an internal space. A support region extends through the internal space; a plurality of thermocouple elements are carried by the support region and are electrically coupled to each other. Each thermocouple element is formed by a first and a second thermoelectrically active region of a first and, respectively, a second thermoelectrically active material, the first thermoelectrically active material having a first Seeback coefficient, the second thermoelectrically active material having a second Seeback coefficient, other than the first Seeback coefficient. At least one of the first and second thermoelectrically active regions is a silicon-based material. The first and second thermoelectrically active regions of each thermocouple element are formed by respective elongated regions extending at a mutual distance into the internal space of the housing, from and transversely to the support region.