Abstract: The present invention provides a method and apparatus for monitoring the state of an attribute of a product during the manufacturing process. The invention employs an intelligent system trained in the relationship between the signatures of the manufacturing process and the product attribute as a function of time. In one embodiment the intelligent system comprises two intelligent systems: the first, trained in the relationship between the signatures of the manufacturing process and one or more signatures of the state of the attribute as a function of time; and the second, trained in the relationship between the product-state signatures as a function of time and the product attribute as a function of time. The disclosed apparatus can be an integral part of the manufacturing machinery allowing the process to continue until the exact moment when the desired state is achieved.

Abstract: An ellipsometric method for process control in the context of device fabrication is disclosed. An ellipsometric signal is used to provide information about the device during the fabrication process. The information is used to better control the process. An ellipsometric signal of a particular wavelength is selected. The signal is selected based on the composition and thickness of the films on the substrate through which the ellipsometric signal will pass before it is reflected from the substrate. Once the appropriate wavelength is determined, the ellipsometric signal is used to monitor the thickness of the films on the substrate over time, to assist in controlling the deposition and removal of films on the substrate, and to perform other process control functions in the context of device fabrication. The ellipsometric method is used to control the deposition and removal of films that underlie patterned masks with aspect ratios of 0.

Abstract: Silicon nitride regions suitable for applications such as capping layers in integrated circuit fabrication are produced by an advantageous plasma deposition process. This process utilizes a combination of gases, including a silicon-containing gas, a nitrogen-containing gas, a fluorine-containing gas, and a hydrogen-containing gas. Silicon nitride having a low density of defect states and thus having excellent dielectric properties is produced.

Abstract: Anisotropic plasma etching is accomplished utilizing a helical resonator operated at relatively low gas pressure. The use of this combination yields an extremely high flux of ionic species with resulting rapid anisotropic etching. A helical resonator in conjunction with suitable precursors is also quite useful for plasma induced deposition.

Abstract: A process is described for preparing III-V compound semiconductor devices (e.g., gallium arsenide devices) in which gaseous bromine or chlorine is used as an etch. This etch procedure provides highly uniform etching. High selectivity for etching gallium arsenide in the presence of gallium aluminum arsenide may be obtained by the addition of oxidant gas such as water vapor.

Abstract: A highly selective--greater than 100 to 1--etch for silicon, tantalum, tantalum silicide and tantalum nitride is achieved by using polyatomic halogen fluorides. The selectivity is achievable without employing plasmas or wet etching.

Abstract: Crystallographic etching in III-V semiconductor materials such as GaAs is achieved, for example, by utilizing a suitable halogen containing entity such as chlorine, bromine and iodine. This crystallographic etching yields in one embodiment essentially vertical surfaces of optical quality. Therefore, the procedure is useful in fabricating integrated circuits and in producing optical devices.