About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
ECTC 2011
Conference paper
Fluxless bonding for fine-pitch and low-volume solder 3-D interconnections
Abstract
Fluxless bonding can be used for fine-pitch low-solder-volume interconnections for three-dimensional large-scale integrated-circuit (3D-LSI) applications. Surface treatments with hydrogen radicals, formic acid, vacuum ultraviolet (VUV), and Ar plasma were evaluated as candidate methods for fluxless bonding. Three-m-thick Sn solders were evaluated for intermetallic-compound (IMC) bonding of 3D integration as a target material for fluxless bonding. X-ray photoelectron spectroscopy (XPS), Auger electron spectro-scopy (AES), time-of-flight secondary ion mass spectrometry (TOF-SIMS), a scanning electron microscope (SEM), and a focused ion beam scanning ion microscope (FIB-SIM) were used to examine the samples. The experiments shows solder oxides and organic contaminants on the surfaces of the micro-bumps were most effectively eliminated without flux by hydrogen radical treatment among various treatments we evaluated. Bonding strength was also improved by the hydrogen radical treatment, since the shear strength was more than 50 times stronger than that of the untreated samples. © 2011 IEEE.