Pulse durability of thin-film resistors embedded in printed circuit boards

The passives (resistors, capacitors, inductors) embedded in printed circuit boards (PCBs) can improve electrical properties and reliability of electronic systems. Pulse durability is an important parameter of passive components and active devices. In the case of resistors it allows to determine many properties including maximum power dissipation, resistance change or phenomena occurring in resistor structures after pulse surging. Furthermore pulse durability defines utility for pulse circuits. Thus this work presents pulse durability of thin-film resistors made on the surface or embedded in Printed Circuit Boards. Investigated test structures were made of nickel-phosphorus (Ni-P) alloy on FR-4 laminate with sheet resistance 25 Ω/sq or 100 Ω/sq. Pulse durability was determined by calculating the maximum nondestructive electric field, maximum nondestructive surface power density or maximum nondestructive volume power density. These parameters were determined in dependence on pulse duration, resistor geometry (length, width, aspect ratio), type of cladding, laser trimming and accelerated aging process.