Focused ion beam metrology
AssigneeInternational Business Machines Corporation
InventorAlfred Wagner
Life of this patent
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Abstract
A focused ion beam metrology device and method are disclosed. A focused ion beam is used to measure dimensions of semiconductor features, such as top-down linewidth measurement. Low intensity focused ion beams form top view images of the semiconductor. High intensity focused ion beams etch the semiconductor in the presence of etch-enhancing material. A crater is etched to expose a cross-section the of semiconductor. The cross-section is imaged by directing low intensity focused ion beams toward the cross-section. This may be achieved by tilting the semiconductor. A three dimensional profile of a feature may be formed by successively etching the feature top surface and forming a top view image thereof. Overlaying the successive top view images forms the three dimensional profile.
Claims43
A focused ion beam metrology device comprising:
- a focused ion beam source which produces low intensity focused ion beams directed to a semiconductor device having features thereon;
- a detector which detects electrons or ions emitted from said semiconductor device;
- a processor which receives data from said detector and measures dimensions of said features from said data;
- a discharge device which introduces an etch-enhancing material toward said semiconductor device;
- and
- a control device connected to said ion beam device to vary intensity of said focused ion beams for generating high intensity focused ion beams to etch said semiconductor device;
- said etch-enhancing material being one of H.sub.2 O gas, H.sub.2 O.sub.2 gas, and a combination of said two gases.
A method of measuring size of a polymer feature of a semiconductor device comprising the steps of:
- (a) scanning a semiconductor device with low intensity focused ion beams from an ion beam source;
- (b) detecting electrons or ions emitted from said semiconductor device using a detector;
- and
- (c) measuring a linewidth of said polymer feature from said detected electrons or ions by a processor connected to said detector.
A method of forming a three dimensional profile of a feature of a semiconductor device comprising the steps of:
- introducing an etch-enhancing material toward said semiconductor device through a discharge device;
- etching a top surface of said feature with a high intensity focused ion beam from an ion beam source;
- forming a top-down image of said to top surface on an image forming device connected to a processor;
- repeating said etching and forming steps until said feature is completely etched from top to bottom to form successive top-down images of said etched feature;
- and
- overlaying said top-down images of said feature by said processor to form said three dimensional profile of said feature.
A method of measuring a cross-section profile of a semiconductor device comprising the steps of:
- introducing an etch-enhancing material toward said semiconductor device through a discharge device, said etch-enhancing material being one of H.sub.2 O gas, H.sub.2 O.sub.2 gas, and a combination of said two gases;
- etching a crater to expose said cross-section by a high intensity focused ion beam generated from a first ion beam source;
- directing a low intensity ion beam toward said cross-section;
- and
- forming an image of said cross-section on an image forming device from low intensity ion beams generated from said ion beam source and reflected from said cross-section.
A method of etching a semiconductor device comprising the steps of:
- introducing an etch-enhancing material toward said semiconductor device through a discharge device;
- and
- etching said semiconductor device with a focused ion beam from an ion beam source;
- wherein said introducing step increases speed and accuracy of said etching step and said etch-enhancing material is one of H.sub.2 O gas, H.sub.2 O.sub.2 gas, and a combination of said two gases.
A method for carrying out focused particle beam machining of material from a substrate comprising the steps of:
- (a maintaining the substrate within a vacuum;
- (b) applying water vapor to the substrate;
- and
- (c) bombarding the substrate and applied water vapor within a focused particle beam.
A method for focused particle beam machining of a substrate, said substrate comprising a first material and a second material, said method comprising the steps of:
- (a) maintaining the substrate within a vacuum;
- (b) applying water vapor to the substrate;
- and
- (c) bombarding both the first and second materials and applied water vapor with a focused particle beam, said materials selected so that said water vapor selectively increases the rate of removal of the first material.
Dependencies are inferred from the claim text.