Thermal conductivity of 
SrVO3−SrTiO3
 thin films: Evidence of intrinsic thermal resistance at the interface between oxide layers

A new and relatively simple method, described for thermal conductivity measurement of dielectric thin films, is presented in this paper. This new technique, the thermal resistance method, can be applied to determine cross-plane thermal conductivity of thin film by electrical heating and sensing techniques without traditional free standing structure design. A slender metal line, deposited on top of dielectric film, is used to measure and extract thermal resistance (Rc) of composite structure, including substrate and dielectric film. A 2-D analytical solution is derived to get thermal resistance (Rs) of substrate. Therefore, the thermal resistance of thin film (Rf) is calculated by subtracting Rs form Rc and thermal conductivity of thin film can also be extracted from thermal resistance. The measurement data of silicon dioxide with difference thickness are verified by using previous scientific literatures. In addition, the measuring results also show good agreement with those measured by 3 omega method. According to advantages of rather rapid and accuracy, this new technique has potential to develop to be an in-line test key for MEMS and IC relative industries.

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Thermal Properties of Thin Films

MRS Proceedings ◽

10.1557/proc-284-133 ◽

1992 ◽

Vol 284 ◽

Cited By ~ 5

Author(s):

J. C. Lambropoulos ◽

S.-S. Hwang

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Conductivity ◽

Thermal Properties ◽

Thermal Resistance ◽

Interfacial Thermal Resistance ◽

Bulk Solid ◽

Ceramic Films ◽

Film Substrate ◽

Conductivity Of Thin Films

ABSTRACTWe summarize various measurements of the thermal conductivity of thin ceramic films which show that the thermal conductivity of thin films with thickness in the micron and sub-micron range may be up to two orders of magnitude lower than the thermal conductivityof the corresponding bulk solid. The reduction in the thin film effective thermal conductivity is attributed to the interfacial thermal resistance across the film/substrate interface.

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Thermo-Mechanical Study of AlN Thin-Films As Heat Spreaders in III-V Photonic Devices

ASME 2017 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2017-74184 ◽

2017 ◽

Cited By ~ 1

Author(s):

Shenghui Lei ◽

Ertugrul Kardemir ◽

David McCloskey ◽

John F. Donegan ◽

Ryan Enright

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Residual Stress ◽

Thermal Resistance ◽

Semiconductor Lasers ◽

Compressive Residual Stress ◽

Silicon On Insulator ◽

Tensile Failure ◽

Processing Temperature ◽

Residual Stress State

Ridge-type hybrid III-V active waveguides on silicon-on-insulator (SOI) substrates demonstrate poor thermal performance due to several factors. One aspect of their typical design that leads to large thermal resistance is the use of polymer-based optical cladding around the waveguide. To address this issue, we have been exploring the use of deposited aluminium nitride (AlN) as an alternative optical cladding material. AlN is an excellent dielectric with optical properties making it suitable as a cladding around III-V waveguides. Crucially, this material can demonstrate thermal conductivities ∼100 times larger than current polymer cladding materials such as benzocyclobutene (BCB). Electro-thermo simulation results suggest that replacing BCB with AlN could reduce device thermal resistance by ∼2 times. However, our previous linear elastic mechanical modelling indicates that mismatched thermal expansion has the potential to cause mechanical tensile failure in the III-V waveguide when cooled from the processing temperature to room temperature if AlN is deposited in a neutral residual stress state. Here, to facilitate the design of encapsulated reliable hybrid semiconductor lasers, we extend our finite element, electro-thermo-mechanical model to include a residual stress in the deposited AlN. Using the Christensen criterion to define the maximum allowable stress in the device, our simulations indicate that there is a window of residual compressive stress in the AlN where mechanical failure may be avoided. To assess the feasibility of accessing this region of compressive residual stress while maintaining suitable thermal properties in the deposited AlN, we measure the thermal conductivity of AlN thin films (∼1.6 μm thick) deposited on silicon using a time-domain thermo reflectance (TDTR) setup. Stress measurements demonstrate compressive residual stresses ranging from ∼0 to −0.5 GPa. The TDTR measurement results reveal a similar thermal conductivity of ∼155 Wm−1K−1 over the entire range of compressive residual stress. These results strengthen the promise of encapsulating III-V active waveguides with AlN that simultaneously satisfy both thermal and mechanical requirements.

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Measurement of Thermal Conductivity and Interface Thermal Resistance of Multilayered Thin-Films Using Variable Pulse-Width Transient Thermoreflectance

Volume 9: Micro- and Nano-Systems Engineering and Packaging, Parts A and B ◽

10.1115/imece2012-88747 ◽

2012 ◽

Cited By ~ 1

Author(s):

Mihai G. Burzo

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Thermal Resistance ◽

A Priori ◽

Unknown Parameters ◽

Non Invasive ◽

Interface Thermal Resistance ◽

Microelectronics Industry ◽

Measurement Uncertainties ◽

Conductivity Of Thin Films

This work discusses the use of a non-contact, non-invasive and in-situ measurement approach for determining the thermal conductivity of thin films used in the microelectronics industry, along with the interface thermal resistance between the films. The approach is based on the thermoreflectance method, where the change in the surface temperature is measured by detecting the change in the reflectivity of the sample. The results presented in this paper show that by using different pulse-widths for the heating laser, as well as a variable wavelength for the probing laser, the proposed method enables the measurement of several unknown parameters in a multi layered sample, which is representative of modern devices developed by the microelectronics industry. In addition, it is shown that the method can be further improved to minimize the measurement uncertainties by estimating a-priori the optimum thickness of the metal absorption layer that needs to be used. A property called responsivity is described, and it is shown that maximizing its value is indeed producing the lowest measurement uncertainties. An objective of this work is to provide guidance to investigators building similar systems and help others improve existing systems.

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