This paper describes various package related failure mechanisms observed in the plastic surface mount Ball Grid Array (BGA) package. Two types of plastic BGA packages commonly known as 225 OMPAC™ (Over Molded Pad Array Carrier) and 225 GTPAC (Glob Top Pad Array Carrier) are covered in this paper. The GTPAC is not offered as a production package, but it is used for commercial prototypes and evaluations. The failure analysis results discussed in this paper are primarily of the devices which failed at different times during various reliability and qualification testing over a period of two years. The failure analysis results of field returns (about 10% of al the devices analyzed) from customers for the same period are also included in this study. Of all the devices in the BGA packages which were failure analyzed, about 50% lailed due to package related problems. All the package related failures fall into two major categories of failure mechanisms, package delamination and cracked open copper traces on the printed circuit board (PCB). The delamination resulted in a variety of physical damage such as lifted ball bonds at the die pads, fractured bond wires in the span as well as at the heel of the crescent bonds on the PCB substrate, and cracking of the encapsulant. The copper traces cracked from two types of stresses, mechanical and thermal. In addition, some of the techniques used for the failure analysis are briefly discussed in this paper.

A functional DRAM with higher data retention and NH3. CVD TiN was deposited using TiCl4 and NH3. IOOA characteristics than a planar access device has been demonstrated, blanket films were characterized by x-ray reflectivity (XRR) using a metal gate recessed access device (RAD). Chemical vapor and x-ray diffraction (XRD). As observed from the XRD deposition (CVD) and atomic layer deposition (ALD) were used to patterns ( Fig.3 and 4), CVD TiN films are crystalline with deposit titanium nitride (TiN) and tantalum nitride (TaN), colu respectively. CVD TiN and ALD TaN-CVD TiN laminate gate columnar grains, and grain growth post heat treatment is stacks were integrated with a RAD module. ALD TaN-CVD TiN minimal. ALD TaN films are nanocrystalline as deposited and laminate gates showed enhanced drive current (IDs), higher exhibit non-uniform crystallinity post heat treatment. Blanket transconductance (GM), higher mobility (PEFF) and reduced off stress variation of TiN film versus thickness is shown in Fig.5. current (IOFF) characteristics compared to CVD TiN gates. Device Density (extracted from XRR) variation due to heat treatment is characteristics and reliability data for both the planar devices and RADs are presented. The ALD TaN-CVD TiN laminate metal gate plotted in Flg.6 for TaN and TiN. TEM images (Fig 7) of 0ouA RAD showed much improved data retention characteistics TaN flm post heat treatment show crystallites in an amorphous compared to a conventional planar device with a poly silicon gate. matrix. Post heat treatment, the interface of TaN/SiON was The optimum thickness of ALD TaN in the laminate stack is smoother and more distinct compared to the rough TiN/SiON discussed.

A 23-year-old woman with systemic lupus erythematous, lupus nephritis (class IV), hypertension with retinopathy, chronic anemia, and end-stage renal disease on peritoneal dialysis since October 2013 presented to the emergency department in January 2014 with abdominal pain, nausea, vomiting, and diarrhea for one week. She admitted that during a re-

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