X-ray Diffraction Residual Stress Measurement at Room Temperature and 77 K in a Microelectronic Multi-layered Single-Crystal Structure Used for Infrared Detection

• Published in: Journal of electronic materials Vol. 47; no. 11; pp. 6641 - 6648
• Main Authors: Lebaudy, A.-L., Pesci, R., Fendler, M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-11-2018; Springer Nature B.V; Institute of Electrical and Electronics Engineers
• Subjects: Axial stress; Characterization and Evaluation of Materials; Chemistry and Materials Science; Circuit reliability; Cryogenic temperature; Crystal structure; Crystals; Deformation; Diffraction; Electronic assemblies; Electronics and Microelectronics; Engineering Sciences; Infrared detectors; Instrumentation; Materials; Materials Science; Mechanical properties; Mercury cadmium tellurides; Multilayers; Optical and Electronic Materials; Residual stress; Room temperature; Silicon; Single crystals; Solid State Physics; Stress measurement; Stress tensors; Tensors; X-ray diffraction; Semiconductor compounds; cryogenic temperature; x-ray diffraction; thermomechanical processing; residual stresses; Residual stresses; Thermomechanical processing; Cryogenic temperature
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-018-6560-7

The electronic assembly considered in this study is an infrared (IR) detector consisting of different layers, including (111) CdHgTe and (100) silicon single crystals. The processing steps and the low working temperature (77 K) induce thermomechanical stresses that can affect the reliability of the thin and brittle CdHgTe detection circuit and lead to failure. These residual stresses have been quantified in both CdHgTe and silicon circuits at room temperature (293 K) and cryogenic temperature using x-ray diffraction. A specific experimental device has been developed for 77 K measurements and a method developed for single-crystal analysis has been adapted to such structures using a laboratory four-circle diffractometer. This paper describes the methodology to obtain the deformed lattice parameter and compute the strain/stress tensors. Whereas the stresses in the CdHgTe layer appear to be negative at room temperature (compressive values), cryogenic measurements show a tensile biaxial stress state of about 30 MPa and highlight the great impact of low temperature on the mechanical properties.