by Anton Shilov
07/30/2008 | 06:29 AM
ATI, graphics product group of Advanced Micro Devices, has issued a statement to its partners claiming that its ATI Mobility Radeon graphics processing units (GPUs) have no issues with packaging, unlike competing solutions from Nvidia Corp. Surprisingly, AMD has shred some light on the possible issue that affects the mobile GeForce graphics chips.
“In the past couple of weeks there has been considerable media attention regarding product reliability of certain notebook GPU die/packaging material failures. AMD is pleased to reassure our customers that our ATI Mobility Radeon GPUs are not experiencing any such abnormal field failures,” a statement from AMD seen by X-bit labs reads.
According to ATI, once the RoHS compliancy became compulsory several years ago, the company transited its ASIC packaging process from restricted solder bumping material (which is used to attach the ASIC die to the substrate) to the use of eutectic solder bumping. A “eutectic” or “eutectic mixture” is a mixture at such proportions that the melting point is as low as possible, and which all ingredients crystallize simultaneously at this temperature from melt liquid. ATI chose eutectic instead of the alternative high-lead bumps (also allowable by RoHS) because the latter, according to the statement, were known to be more fragile and subject to field failure issues if not implemented properly.
After initiating to use the eutectic bumping material, ATI started to specifically design with it and implemented a specialized power redistribution layer (RDL) to help ensure a reliable device.
“Package reliability is a matter of overall design and implementation. Factors such as the power distribution in the design of the ASIC, bumping process, bumping material and the techniques used to adhere bumps to the wafer all play an important role in the reliability of the packaged part. We would welcome the opportunity to review our packaging and quality processes with you if further information is required,” the statement by AMD claims.
Even though Nvidia Corp. has never issued official comments regarding the materials it uses to attach its chips to substrate, it is highly likely that the company has, at least in certain points in the past, utilized substances that were not as reliable as eutectic mixtures utilized by AMD’s ATI in conjunction with RDL.
Nvidia did not comment on the news-story.