Abstract:
The present invention provides a process for locally removing at least a portion of a material layer structure in which first and second materials are provided, the second material having a higher etch rate by an activated reaction gas than the first material. The second material is disposed over at least a portion of the first material. A reaction gas flows adjacent a portion of the second material to be removed. The reaction gas is chemically reactive with at least the second material to form volatile reaction products when activated by a focused particle beam, but does not spontaneously react with the second material.The portion of the second material to be removed is irradiated with a focused particle beam. Exemplary particle beams are focused ion beams and electron beams. The focused particle beam initiates a chemical reaction between the portion of the second material and the reaction gas, forming volatile reaction products which desorb from the substrate and are removed. This technique finds particular application for removal of opaque defects on tungsten absorber x-ray masks.
Abstract:
Repair of transparent errors in masks utilized for lithographic processes in the manufacture of devices is accomplished by a particularly expedient procedure. In this procedure a metal ion beam such as a gallium ion beam is directed to the region that is to be repaired. An organic gas, including a material having an aromatic ring with an unsaturated substituent, is introduced into this region. The interaction of the gas with the ion beam produces an opaque adherent deposit. The resolution for this deposition is extremely good and is suitable for extremely fine design rules, e.g., 1 .mu.m and below.
Abstract:
A reflection filter is disposed on a solid state laser so as to preferentially reflect TE or TM modes and to suppress oscillation within the resonator of the non-reflected modes. In one embodiment, the filter includes a layer having a plurality of grooves which may be straight and parallel or curved to approximate the mode shape. In another embodiment, the filter includes a polarization sensitive film, without grooves, which either absorbs or transmits the undesired mode. Specifically described is a buried heterostructure semiconductor DFB laser with such a reflection filter formed on at least one facet thereof.
Abstract:
A process for controlling the stress of multilayer films formed on a substrate is disclosed. A plurality of periods, each period having at least two layers of material wherein one of the layers of material is under compressive stress and the other layer of material is under tensile stress, are formed in a substrate. The stress in the multilayer film is controlled by selecting a thickness for the layer under compressive stress and a thickness for the layer under tensile stress that will provide a multilayer film of the desired stress. The thickness of each layer is about 0.5 nm to about 10 nm. Multilayer films with a stress of about -50 MPa to about 50 MPa are obtained using the present process. The present invention is also directed to masks with such multilayer films.
Abstract:
Fine featured devices are produced by a series of fabrication steps including exposing selective surface regions to irradiation, e.g. to an ion beam, generally to result in removal of masking material within irradiated regions. In most instances, subsequent etching is under conditions such that bared material is preferentially removed. Etch-removal and irradiation are such that overgrown material is of device quality at least in etched regions. The inventive process is of particular value in the fabrication of integrated circuits, e.g. circuits performing electronic and/or optical functions. The inventive process is expediently used in the fabrication of structures having minimum feature size of 1 micrometer and smaller. Patterning is dependent upon masking material of a maximum thickness of 100 .ANG..
Abstract:
When high-vacuum methods are used in the manufacture of miniaturized devices such as, e.g., semiconductor integrated-circuit devices, device layers on a substrate are preferably patterned without breaking of the vacuum. Preferred patterning involves deposition of a semiconductor mask layer, generation of the pattern in the mask layer by ion deflected-beam writing, and transfer of the pattern by dry etching. When the mask layer is an epitaxial layer, further epitaxial layer deposition after patterning may proceed without removal of remaining mask layer material.