This article shows various factors that influence the thermal-cycling reliability of semiconductor devices utilizing the lead-on-chip (LOC) die attach technique. This work details how the modification of LOC package design as well as the back-grinding and dicing process of semiconductor wafers affect passivation reliability. This work shows that the design of an adhesion tape rather than a plastic package body can play a more important role in determining the passivation reliability. This is due to the fact that the thermal-expansion coefficient of the tape is larger than that of the plastic package body. Present tests also indicate that the ceramic fillers embedded in the plastic package body for mechanical strengthening are not helpful for the improvement of the passivation reliability. Even though the fillers can reduce the thermal-expansion of the plastic package body, microscopic examinations show that they can cause direct damage to the passivation layer. Furthermore, experimental results also illustrate that sawing-induced chipping resulting from the separation of a semiconductor wafer into individual devices might develop into passivation cracks during thermal-cycling. Thus, the proper design of the adhesion tape and the prevention of the sawing-induced chipping should be considered to enhance the passivation reliability in the semiconductor devices using the LOC die attach technique.

The purpose of this study was to examine the effects of stroke patients' cognitive score on their the activities of daily living. The subjects of this study were 30 stroke patients who were admitted to Te-Bong hospital from November, 2002 to March, 2003. The subjects were administerd an MMSE as a cognitive assessment and an MBI as a functional assessment upon referral to physical therapy initially. The results were as follows: 1. The MMSE scores for the stroke patients were related to the patients' abilities to perform their activities of daily living. The changes of MBl scores significantly correlated with the changes of MMSE scores (p<.05). 2. The subjects with left hemispheric lesion scored higher in MMSE than those with right hemispheric lesions (p<.05). 3. The hemispheric lesions did not significantly affect the activities of daily living score (p>.05).