Electrode tuning method and apparatus for a layered heater structure

A resistive heater apparatus comprising:

• a base substrate;
• at least one film electrode pattern deposited on the base substrate, said at least one film electrode pattern being comprised of at least one segment including a physical feature which alters an electrical current flow and/or reduces the effective cross-section of said at least one segment.

A resistive heater apparatus prepared by a process comprising the steps of:

• (i) virtually partitioning a predetermined pattern of the electrode layer into at least one segment;
• (ii) identifying those virtually partitioned segments from among said at least one segment having an electrical resistance that deviates from a target segment resistance by an amount exceeding an absolute value of a pre-determined threshold, and
• (iii) introducing at least one perforation into each of the identified virtually partitioned segments to sufficiently modify the electrical resistance of the identified virtually partitioned segments such that the modified electrical segment resistance does not deviate from said target segment resistance by an amount exceeding said absolute value of said pre-determined threshold.