A stage includes a first metal plate, a second metal plate below the first metal plate, a heat insulating portion including a first space provided in the first metal plate and a second space provided in the second metal plate, and a circulating flow path and a heater with the insulating portion therebetween. In a cross-sectional view, a width of the heat insulating portion in the first metal plate is different from a width of the heat insulating portion in the second metal plate.

A stage includes a shaft, a first supporting plate over the shaft, a heater arranged in a trench formed in the first supporting plate, and a gas-supplying tube arranged in the shaft and configured to blow a gas to the first supporting plate. The first supporting plate may have a disk shape, and a cross section of the gas-supplying tube parallel to a surface of the first supporting plate may overlap a center of the disk shape. The first supporting plate may be configured to block the gas so that the gas is not released to a chamber in which the stage is arranged.

A process for manufacturing a PTC heating element that includes at least one PTC component (20) and a carrier (14, 16) permanently connected to the PTC component on at least one side (24, 26) of thereof The process includes applying electrically conductive sintered material (28, 30, 36, 38) on the one side of the PTC component, which side is to be permanently connected to a carrier. Subsequently, a contact of the PTC component is established with at least one carrier such that sintered material, which was applied between the PTC component and the carrier and is intended for establishing a connection between the at least one PTC component and the at least one carrier, is positioned. The sintered material, which material has been positioned between the PTC component and the carrier, is sintered by heating or/and by applying pressure.

A process for manufacturing a PTC heating element that includes at least one PTC component (20) and a carrier (14, 16) permanently connected to the PTC component on at least one side (24, 26) of thereof The process includes applying electrically conductive sintered material (28, 30, 36, 38) on the one side of the PTC component, which side is to be permanently connected to a carrier. Subsequently, a contact of the PTC component is established with at least one carrier such that sintered material, which was applied between the PTC component and the carrier and is intended for establishing a connection between the at least one PTC component and the at least one carrier, is positioned. The sintered material, which material has been positioned between the PTC component and the carrier, is sintered by heating or/and by applying pressure.