Laser scanning thermoreflectance imaging system using galvanometric mirrors for temperature measurements of microelectronic devices

We present a thermoreflectance imaging system using a focused laser sweeping the device under test with a scanner made of galvanometric mirrors. We first show that the spatial resolution of this setup is submicrometric, which makes it adapted to microelectronic thermal measurements. Then, we studied qualitative temperature variations on two dissipative structures constituted of thin (0.35μm) dissipative resistors, the distance between two resistors being equal to 0.8 or 10μm. This technique combines sensitivity and speed: it is faster than a point classical thermoreflectance technique and, in addition, more sensitive than a charge-coupled device thermoreflectance imaging technique