Abstract: A container having an indicator for detecting the presence of chemical elements is provided. In one embodiment, the container comprises a cavity therein for receiving an article having a first metallic element, the cavity being substantially sealed from a surrounding environment outside the container. An indicator is disposed within the sealed cavity, the indicator having a second metallic element with a standard potential less than the standard potential of the first metallic element, whereby a change in state of the second metallic element alerts an operator to the presence of a predetermined chemical element within the container.

Abstract: A container having an indicator for detecting the presence of chemical elements is provided. In one embodiment, the container comprises a cavity therein for receiving an article having a first metallic element, the cavity being substantially sealed from a surrounding environment outside the container. An indicator is disposed within the sealed cavity, the indicator having a second metallic element with a standard potential less than the standard potential of the first metallic element, whereby a change in state of the second metallic element alerts an operator to the presence of a predetermined chemical element within the container.

Abstract: A method of forming very small silicon nitride spacers in split-gate flash EPROMs is disclosed which prevent the occurrence of “write disturb”, unwanted reverse tunneling, or erasing. This is accomplished by forming spacers with well controlled dimensions and well defined shapes through a judicious combination of dry etch with wet over-etch technique. The wet etch along with the dry etch widens the process window from a few seconds to several minutes so that the small dimensioned silicon nitride spacers can be better controlled than it has been possible in the past. In a second embodiment, the step of over-etching of the spacers is combined with the step of stripping off of an implant photomask, thus, shortening the manufacturing product cycle.