The performance and appearance of an electrophoretic display is strongly dependent on the stability of the colloidal suspension in the device. Two primary degradation modes in a suspension have been identified. One is classified as pigment agglomeration which is caused by an insufficient repulsive barrier between particles; the other is classified as pigment clustering which is caused by fluid motion within the cell. Both forms of instabilities are detrimental to the life of the display. The concept of colloid stability will be reviewed briefly and its relation to the image device will be discussed. The mechanism by which the suspension instabilities develop and the methods by which they can be eliminated will be described. Properly stabilized suspensions in a device have survived in excess of 2.5×108 switches (15 600 h) with no serious signs of degradation.

The electrical properties of Si3N4/SiO2/Si structures, which are currently used in integrated circuits technology, are largely dependent upon the structure and the chemical composition of the interface regions which may be a few Å thick. Such locked-in regions are difficult to analyze by destructive techniques like secondary ion mass spectroscopy (SIMS) or Auger electron spectroscopy (AES) with ion milling. We show that spectroscopic ellipsometry, operating in the 1.5–6 eV range, is capable of nondestructively analyzing the interface region. The method is demonstrated on standard atmospheric pressure chemical vapor deposition (CVD) nitride layers and the results are compared with ion-milling AES data. The effects of O2 annealing and NH3:SiH4 ratios are also investigated.

Efficient red GaP LED's have been fabricated by compensating the p side of the junction with a donor. The observed efficiency in the diodes fabricated remains invariant over a wide range of net acceptor concentration. Utilizing the recombination kinetic analysis of Jayson, Bhargava, and Dixon, it is shown that better injection efficiencies and higher Zn–O complex concentrations are the cause for this invariance. The compensation technique potentially offers a commercial LPE growth process from which high-efficiency low-cost LED's could be fabricated.