Thin film resistor having surface mounted trimming bridges for incrementally tuning resistance

A multilayer substrate, comprising:

• an uppermost layer defining an uppermost surface of the multilayer substrate;
• a plurality of lower layers that are disposed underneath the uppermost layer;
• and
• a resistor assembly, comprising:
• a surface mounted layer comprising a first conductive trace, a second conductive trace, and a plurality of trimming bridges that electrically couple the first conductive trace to the second conductive trace, wherein the surface mounted layer is disposed along the uppermost layer of the multilayer substrate;
• a second layer disposed underneath the surface mounted layer within one of the plurality of lower layers, wherein the second layer comprises an embedded thin film resistor electrically coupled to the surface mounted layer, wherein the plurality of trimming bridges are each removable to increase a resistance of the embedded thin film resistor;
• and
• a plurality of vias that electrically couple the first conductive trace of the surface mounted layer to the embedded thin film resistor.

A method for tuning a resistor assembly, the method comprising:

• obtaining an initial resistance measurement of the resistor assembly by probing a surface mounted layer of the resistor assembly, wherein an embedded thin film resistor is electrically coupled to a tuning pattern of the surface mounted layer, wherein the tuning pattern comprises one or more pairs of conductive traces;
• comparing the initial resistance measurement to a defined resistance criteria;
• and
• in response to determining the initial resistance measurement does not satisfy the defined resistance criteria, removing one or more trimming bridges that are part of a plurality of trimming bridges of the surface mounted layer, wherein each pair of conductive traces are electrically coupled to one another by the plurality of trimming bridges.