Thin Film Resistor is:
Resistive material is deposited extremely thinly and evenly onto the substrate then patterned with photolithography to be made into resistive element.
Characteristics of thin film resistors
Smooth electron flow through thin film can suppress the noise and high frequency harmonics
Multiple resistors within chip attenuators are made of thin film.
The advantage of thin film resistor (less high frequency harmonics)
As shown below, thin film resistive element has much lower third harmonic distortion level (compared in resistors)