Patent ID: 7536915

Claim:
Method for the production of a vacuum measuring cell with a diaphragm ( 2 ) as pressure transducer, wherein on the one side of the diaphragm ( 2 ) at a spacing a first housing plate ( 1 ) is disposed sealing in the margin region with a joining means ( 3 ), such that between them a reference vacuum chamber ( 7 ) is formed and that on the other side of the diaphragm ( 2 ) at a spacing a second housing plate ( 4 ) is disposed sealing in the margin region with a joining means ( 3 ), such that between them a measuring vacuum chamber ( 9 ) is formed, and that the second housing plate ( 4 ) includes an opening and connection means ( 5 ) communicating with the opening and the measuring vacuum chamber ( 9 ) disposed sealing with joining means ( 3 ) for the connection of the measuring vacuum chamber ( 9 ) with the medium to be measured, wherein the diaphragm ( 2 ) and the housing plates ( 1 , 4 ) are comprised of a metal oxide, characterized in that the measuring cell is coated in a vacuum chamber ( 64 ) using an ALD method and the material deposition takes place through the opening of the measuring cell and the connection means ( 5 ) such that the inner wall of the measuring vacuum chamber ( 9 ) and the opening with the connection means ( 5 ) are covered with a protective layer ( 13 ) such that at least the joining means ( 3 ) for the diaphragm ( 2 ) is protectively covered, at least one diaphragm measuring cell ( 8 ) being placed as a substrate ( 63 ) in the vacuum chamber ( 64 ) on a substrate holder ( 62 ) which includes a heating arrangement, and subsequently the vacuum chamber ( 64 ) is evacuated with a pump system ( 52 , 53 , 54 ) and that, after the evacuation is completed to a desired pressure, the coating process takes place in that at least two precursor gases ( 57 , 58 ) are sequentially introduced into the vacuum chamber ( 64 ) at predetermined time intervals wherein between each of these steps the chamber is purged with an inert purge gas ( 65 ) for a predetermined time and that this cycle is repeated several times such that from individual chemically reacted atomic coats a metal oxide layer ( 13 ) with desired total thickness is deposited.