Diamond micro-Raman thermometers for accurate gate temperature measurements

Abstract

Articles you may be interested inMeasurement of temperature distribution in multifinger AlGaN/GaN heterostructure field-effect transistors using micro-Raman spectroscopy

Experimental Characterization of the Thermal Time Constants of GaN HEMTs Via Micro-Raman Thermometry

“…Similar to previous works, the transient temperature profile in Fig. 3(c) rises rapidly during the first ~1 µs interval of the heating phase after the power dissipation pulse begins and continues to rise until the end of the pulse [6]- [11]. The same behavior is observed during the cooling phase in which the temperature rise decreases rapidly then asymptotes.…”

“…To synthesize the optical pulses from the CW laser, we externally modulated the laser intensity with an acousto-optic modulator (AOMO 3200-120, Gooch & Housego). This technique of measuring the transient temperature rise in GaN HEMTs via micro-Raman spectroscopy has been previously reported in the literature [6]- [11]; the unique contribution of this work is the implementation this technique to measure the transient temperature step response and thermal time constant spectrum.…”

“…Given values of ℓ and ℓ extracted from modeling or experiment, one can predict the temperature response to any arbitrary power dissipation profile with linear systems theory or an equivalent Foster RC network [42]. Yet, at a fundamental level, time-resolved micro-Raman thermography as it is implemented in this work and others [6]- [11] measures the temperature response of the DUT to a train of ~10 3 to ~10 6 power dissipation pulses ( ), which can be expressed as…”

A Review of Raman Thermography for Electronic and Opto-Electronic Device Measurement With Submicron Spatial and Nanosecond Temporal Resolution

“…Therefore, this technique is limited to measuring device areas where optical access is not blocked by metal contacts, either in openings between contacts or alternatively measurements can be performed by focusing the laser through the substrate backside, as discussed above, since the measurement can be performed using a sub bandgap laser, in contrast to PL spectroscopy. Although metal surfaces cannot be measured directly using Raman thermography, the application of Raman active micro-thermometers can be used to sense the temperature of these surfaces, including, but not limited to, diamond nanoparticles, TiO 2 nanoparticles or silicon nanowires [44,45].…”

Transient Thermoreflectance for Gate Temperature Assessment in Pulse Operated GaN-Based HEMTs

“…Whereas micro-Raman thermography provides the depth-averaged temperature through the GaN layer, thermoreflectance measurements probe the temperature of the metal surfaces including contacts; Raman thermography can also measure the surface temperature by using micro particle thermometers [13]. The limitation of measuring the surface temperature (e.g., on top of field plates or passivation layers) or the depth averaged GaN temperature, is that the temperature at these locations may be lower than the actual peak gate temperature, which is the most relevant for mean time to failure (MTTF) assessment.…”