| 摘要 |
1,219,990. Electrodes for piezoelectric elements; cavity resonators; magnetrons. LITTON INDUSTRIES Inc. 13 Dec., 1968 [4 Jan., 1968], No. 59385/68. Headings H1D, H1E and H1W. The electrodes of a piezoelectric device consist of several layers of metal including an embossed layer. As shown, the invention is applied to a bimorph having two elements 1, 2 made, e.g. of BaTiO 3 , PZT or LZT or of mixtures of these. The electrodes consist of layers 3, 4, 5 respectively of chromium, copper and gold, these layers being deposited, e.g. by vapour deposition. The central electrode of the bimorph includes a plate 6 of molybdenum provided with deposited layers 7 of gold. The elements 1, 2 are attached to the central plate 6 by means of a bond formed by diffusion of embossed gold sheets 8, 9 into gold layers 5, 7 under heat and pressure (e.g. 40 lb./sq. inch at 600‹ C.). During this process, the gold sheets 8, 9 are flattened, but retain a certain amount of resilience essential to the operation of the bimorph. The plates (not shown to scale) may be of rectangular or annular form. It is stated that they may form part of the walls of a cavity resonator, e.g. of a coaxial magnetron, or can be used for moving tuning means in such cavities. |
