High resolution thermal imaging inside integrated circuits

Abstract

If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -Heating is a major cause of failure in integrated circuits. The authors have designed thermoreflectance-based systems operating at various wavelengths in order to obtain temperature images. This paper aims to explore the possibilities of each wavelength range and detail the charge coupled device (CCD)-based thermal imaging tools dedicated to the high-resolution inspection of integrated circuits. Design/methodology/approach -Thermoreflectance is a non-contact optical method using the local reflectivity variations induced by heating to infer temperature mappings, and can be conducted at virtually any wavelength, giving access to different types of information. In the visible, the technique is now well established. It can probe temperatures through several micrometers of transparent encapsulation layers, with sub-mm spatial resolution and 100 mK thermal resolution. Findings -In the ultraviolet range, dielectric encapsulation layers are opaque and thermoreflectance gives access to the surface temperature. In the near infrared, thermoreflectance is an interesting solution to examine chips turned upside down, since these wavelengths can penetrate through silicon substrates and give access to the temperature of the active layers themselves.Research limitations/implications -The authors show that the illumination wavelength of thermoreflectance should be chosen with care depending on the region of the integrated circuit (surface, above, or below the substrate) to be investigated. Practical implications -This set of versatile and sensitive tools makes thermoreflectance an interesting tool for the semiconductor industry, either during prototyping or as a characterization tool after fabrication. Originality/value -The CCD-based thermoreflectance approach adopted here allows fast, non-contact, high-resolution thermal imaging of integrated circuits.

Unprecedented switching endurance affords for high-resolution surface temperature mapping using a spin-crossover film

“…Contactless far-field optical thermometry techniques, including infrared thermography (IRT) 11 , thermoreflectance microscopy 12 – 14 , optical interferometry 15 , or Raman spectroscopy 16 , 17 , represent to some extent a compromise between overall thermometric performance and general applicability. These techniques usually provide fast (typically ns–µs) thermal-imaging capabilities with diffraction-limited spatial resolution, and represent the industry standard in terms of surface thermal imaging 18 , 19 .…”

Thermoreflectance imaging of laser diodes and VCSELs along and perpendicular to the emission direction

“…The first step is the determination of the optimal wavelength; for each material, qR=qT changes as a function of the wavelength [2]. Before measuring DR, it is necessary to determine the optimal illumination wavelength.…”

Gate-Level Validation of Integrated Circuits With Structured-Illumination Read-Out of Embedded Optical Signatures

“…This approach is based on the presumption that all possible logic errors will be triggered by testing vectors. However, there are two obstacles in this approach [7], [8]. First, the test vectors cannot always provide complete coverage and so cannot always trigger all the erroneous logic [9].…”

“…Yet, the complexity, cost and low throughput of TEM hinders its applicability for authentication. Thermal imaging utilizes predefined test vectors to activate thermal traces on the chip for authentication [7], but it has similar limitations to electrical testing. Inadequate spatial resolution in acoustic and electromagnetic imaging limits their applicability for authentication of modern ICs [5], [10], [11].…”