| 摘要 |
A method of manufacturing a resistor comprises depositing by vacuum evaporation or cathode sputtering a layer of a refractory metal (e.g. Ta, W, Re or Ti) on the surface of an electrically insulating substrate (e.g. of glass or ceramic) and thereafter filling fissure at the grain boundaries of the refractory metal layer by heating (e.g. in a vacuum oven at 500 DEG C.) the refractory metal layer and diffusing a further metal (e.g. Au, Ag, Pt or Pd) into the fissures, the amount of further metal being enough to substantially fill the fissures but less than an amount which would leave a layer of further metal on the surface of the refractory metal layer after the fissures have been filled. The resistor may subsequently be heated at 250 DEG C.in air to stabilize the resistance. The layers of refractory metal R and diffusing metal D may be deposited on the substrate in the order (a) R, D, (b) R, D, R, (c) D, R or (d) a homogeneous layer of R and D may be deposited from a source which is a mixture of the required metals. In (c) a bismuth oxide coating may be used between the substrate and diffusing metal to ensure good adhesion. |
