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A process is provided for manufacturing micromechanical devices formed by joining two parts together by direct bonding. One of the parts (12) is made of silicon and the other one is made of a material chosen between silicon and a semiconductor ceramic or oxidic material. The joint between the two pa

A process is provided for manufacturing micromechanical devices formed by joining two parts together by direct bonding. One of the parts (12) is made of silicon and the other one is made of a material chosen between silicon and a semiconductor ceramic or oxidic material. The joint between the two parts forms a cavity (14) containing the functional elements of the device (11), possible auxiliary elements and a getter material deposit (13).

대표청구항 ▼

I claim: 1. A process for manufacturing a micromechanical device comprising two support parts, one of which (12, 20) comprises silicon and the other of which comprises silicon or a semiconductor, ceramic or oxidic material, functional elements (11) and optional auxiliary elements present on at leas

I claim: 1. A process for manufacturing a micromechanical device comprising two support parts, one of which (12, 20) comprises silicon and the other of which comprises silicon or a semiconductor, ceramic or oxidic material, functional elements (11) and optional auxiliary elements present on at least one of the support parts, and a getter material deposit (13, 24) present on one silicon support part, the method comprising the steps of: providing a first support part (10) on which the functional elements (11) and optional auxiliary elements of the device are built; providing a second support part (20); the first and second support parts being formed such that, when mating, they form a cavity (14) wherein the functional elements, optional auxiliary elements and getter material deposit are housed; approaching the two support parts so as to form the cavity and welding the two support parts by direct bonding; wherein the getter material deposit is formed on the silicon support part by a first operation of forming on the silicon support part an intermediate layer (23) of a vitreous, ceramic or oxidic material having thickness of at least 50 nanometers, and a second operation of depositing a getter material layer (24) having thickness not greater than 10 micrometers onto the intermediate layer; and wherein the getter material comprises an alloy containing zirconium and at least a second element selected from molybdenum, niobium, tantalum and tungsten, wherein zirconium is present in the alloy in a proportion between 70 and 97% by weight. 2. The process according to claim 1, wherein the second element is selected from niobium and tantalum, and zirconium is present in the alloy in a proportion between 85 and 95% by weight. 3. The process according to claim 1, wherein the intermediate layer comprises silicon oxide or nitride and is formed by reaction of the silicon support part with oxygen or nitrogen. 4. The process according to claim 1, wherein the intermediate layer comprises silicon oxide or nitride and is formed by oxygen or nitrogen ion implantation into silicon. 5. The process according to claim 4, wherein the ion implantation is followed by thermal treatments of oxygen or nitrogen diffusion into silicon. 6. The process according to claim 1, wherein the intermediate layer is formed bt cathodic deposition. 7. The process according to claim 6, wherein the cathodic deposition takes place under reactive conditions. 8. The process according to claim 6, wherein the cathodic deposition is carried out on a restricted area of the silicon support part (20) by placing onto the support part a mask (21) with an opening (22) that defines an area of the silicon support part where the deposit will be formed. 9. The process according to claim 1, wherein the operation of deposition of the getter material layer (24) occurs by cathodic deposition. 10. The process according to claim 9, wherein the operation of deposition of the getter material layer (24) is carried out only onto the intermediate layer by placing on the silicon support part (20) a first mask having an opening with a size smaller than or equal to an opening of a second mask used in formation of the intermediate layer, and by aligning the first mask to the silicon support part (20) such that the getter material deposits on the intermediate layer only. 11. The process according to claim 10, wherein the forming operations of the intermediate and getter material layers occur by employing the first and second masks as a same mask (21) with constant alignment with respect to the silicon support part (20). 12. The process according to claim 1, wherein the getter material layer has a thickness between 0.1 and 10 μm. 13. The process according to claim 1, wherein surfaces of the two support parts to be welded together are subjected to cleaning and surface modification treatments before welding. 14. The process according to claim 13, wherein the treatments are selected from mechanical polishing, lapping and chemical washings. 15. The process according to claim 1, wherein the step of welding the two support parts by direct bonding is carried out in the presence of a noble gas at sub-atmospheric pressure.