Patent ID: 7791059

Claim:
An electric device comprising an electrically switchable resistor comprising: a phase change material, the resistor being electrically connected to a first and second electrical contact via a first and second contact area, the resistor extending between the first and second contact area and having a length, defined as the distance between the first and second contact area measured along the resistor, the device further comprising, a body located around the resistor between the first and second contact area, the body being in thermal contact with the resistor, wherein, along the resistor in the direction of its length and between the first contact area and the second contact area the body successively comprises a first region and a second region, the first and second regions defining a first contact surface extending between the first and the second region, the contact surface comprising a first portion which has a first angle of inclination with respect to the length direction of the resistor, the first region having a first material composition, and the second region having a second material composition different from the first material composition, such that the first and second regions have mutually different thermally insulating properties; wherein, along the resistor in its length direction and in between the first and second contact area, the body further comprises a third region and a fourth region, the third and fourth regions defining a second contact surface comprising a second portion having a second angle of inclination with respect to the length direction, the first and second portions being positioned at different locations along the resistor in its length direction, the third region having a third material composition, and the fourth region having a fourth material composition different from the third material composition, such that the third and fourth regions have mutually different thermally insulating properties; and wherein the first and fourth regions have the same materials composition and that the second and third regions have the same materials composition.