Page 368 - Book Hosokawa Nanoparticle Technology Handbook

FUNDAMENTALS CH. 6 EVALUATION METHODS FOR PROPERTIES OF NANOSTRUCTURED BODY

PC
PC

Optical Fiber and
Collimation Head
Adjustable Mirror
Chopper Pump Pulsed Laser

Lens
Z Stage
Driver

Pulse
Specimen Holder Generator
Specimen
XYZ Stage
Lock-in Amplifier
Removable Mirror
Driver
Lens Beam Splitter
CCD Illuminator
Camera
Probe Pulsed Laser
Mirror Removable
Mirror
Lens
Differential
Photodiode Mirror
Motor Optical Fiber and
Collimation Head

Figure 6.3.10
Block diagram of the nanosecond thermoreflectance system.

NMIJ/AIST is also developing the standard of thin 1.2
film thermophysical property by the high-speed laser
flash method under the same scheme as shown in 1.0
Table 6.3.1. The national standard for picosecond
thermoreflectance method was established in 2005. 0.8
The national standard and thin film reference material
are to be developed and supplied in 2007 for nanosec- Thermoreflectance signal /a.u. 0.6
ond thermoreflectance method. 0.4

6.3.6 Summary 0.2
Thermoreflectance methods by picosecond and 0.0
nanosecond light pulse heating have been developed
under the same geometrical configuration as the laser 0 50 100 150 200 250 300
flash method which is the standard method to Delay /ns
measure thermal diffusivity of bulk materials.
Thermal diffusivity values across thin films were Figure 6.3.11
measured with small uncertainty. These high-speed Thermoreflectance signal of molybdenum thin film of 3 m
laser flash methods observe heat diffusion time across thickness sputtered on a glass substrate measured with the
well-defined length of the specimen thickness under nanosecond thermoreflectance system.

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