SThM Temperature Mapping and Nonlinear Thermal Resistance Evolution With Bias on AlGaN/GaN HEMT Devices

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

“…Physical contact techniques, such as scanning thermal microscopy [10], enable high resolution temperature mapping with a potentially high spatial resolution. Their main drawbacks are that quantifying the thermal contact resistance between tip and device surface can be challenging, and also that the active device layers are buried under a relatively thick low thermal conductivity surface passivation layer.…”

Strain and Temperature Dependence of Defect Formation at AlGaN/GaN High-Electron-Mobility Transistors on a Nanometer Scale

“…After device operation to failure, the DRCLS map shown in the center part of Fig. 9(c) with E B = 5 keV of GaN NBE (3.45 eV) intensity reveals major lateral variations, e.g., bright and darker regions (1) and (2), respectively, and the darkest region (3). NBE emission intensity decreases as defect density and alternate recombination pathways increase.…”

“…Temperature distributions of GaN-based HEMTs have been measured by various methods such as micro-Raman method [2], scanning thermal microscopy [3], and depth-resolved cathodoluminescence spectroscopy (DRCLS) [4]. There is a general consensus that temperatures reach a maximum near the drain-side edge of the gate.…”

Scanning Thermal Microscopy (SThM)

“…Simple dc-current Wheatstone bridges, which are used in commercial solutions, are accurate enough to provide basic thermal images. Nonetheless, the measurement resolution and accuracy can be improved by enhancing the probe design [e.g., by using four connections, as did Aubry et al (2007); Janus et al (2010Janus et al ( , 2014] or the measurement setup Wielgoszewski et al, 2011b;Bodzenta et al, 2013). Another important advantage is that thermoresistive probes can be utilized in both P-SThM and A-SThM modes, as the thermoresistor can be used easily as a heat source.…”