Electronic circuit substrate and electronic module using such a substrate

摘要

Substrate for an electronic circuit includes a silicon (Si) wafer (1) coated with a electrically insulating layer (3) of silicon nitride comprising successive tensive and compressive layers so that stress on the Si wafer is compensated. Conductive tracks (4) formed on the insulating layer by metallization are intended for connecting the substrate to electronic components. A thin silicon dioxide (SiO2) layer is interposed between the Si wafer (1) and the insulating layer (3) and serves as a support layer for deposition of the much thicker electrically insulating layer (3). At least one of the electronic components (5) is a power semiconductor component. The silicon nitride layers making up the electrically insulating layer (3) are essentially formed by plasma-enhanced chemical vapor deposition (PECVD), and at least one of the layers is formed by low-pressure chemical vapor deposition. Formation of the conductive tracks (4) is carried out by electrolytic deposition of copper on the electrically insulating layer (3). The lower surface of the Si wafer (1) has grooves that form channels for the flow of a cooling fluid. The lower surface of the Si wafer (1) can be covered with a SiO2 layer and an electrically insulating layer of silicon nitride. An Independent claim is given for an electronic module comprising an electronic device mounted on the above-described substrate.