Research on Tungsten Heating Layer in Phase Change Switch

<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha$</tex> - W has been widely used in device heating layers due to its low electrical resistivity and high mechanical strength. This article prepared <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha$</tex>-W films by selecting the thickness and annealing temperature of W films. At the same time, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha$</tex>-W thin film is used in the indirectly heating phase change switch as the heating layer. The insertion loss of this phase change switch at 1-20 GHz is less than 0.75 dB, and the isolation degree is greater than 22 dB, and the on-off resistance ratio of the switch is greater than 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup>. These are indicating that this switch has good performance.