Abstract: This invention is directed to a method for etching films on semiconductor substrates and cleaning etch chambers. The method includes an improved processing sequence and cleaning method where residue formed from processing a previous substrate are cleaned by the etching process used to remove an exposed layer of material from the present substrate. The process provides improved substrate throughput by combining the step to clean residue from a previous substrate with an etch step conducted on the present substrate. Applicants have found the method particularly useful in processing structures such as DRAM stacks, especially where the residue is formed by a trench etched in the previous silicon substrate and the exposed layer etched from the present substrate is silicon nitride.

Abstract: This invention is directed to a method for rapid plasma etching of materials which are difficult to etch at a high rate. The method is particularly useful in plasma etching silicon nitride layers more than five microns thick. The method includes the use of a plasma source gas that includes an etchant gas and a sputtering gas. Two separate power sources are used in the etching process and the power to each power source as well as the ratio between the flow rates of the etchant gas and sputtering gas can be advantageously adjusted to obtain etch rates of silicon nitride greater than two microns per minute. Additionally, an embodiment of the method of the invention provides a two etch step process which combines a high etch rate process with a low etch rate process to achieve high throughput while minimizing the likelihood of damage to underlying layers. The first etch step of the two-step method provides a high etch rate of about two microns per minute to remove substantially all of a layer to be etched.

Abstract: In a method and apparatus for producing a vapor which serves as a chemical processing material by delivering a carrier gas and a reactive liquid to a vaporizer in which the vapor is produced, the operating state of the vaporizer is monitored by measuring the pressure of the carrier gas being delivered to the vaporizer and producing a detectable indication when the measured pressure exceeds a given value.