Alignment mark structure for laser fusing and method of use
AssigneeInternational Business Machines Corporation
InventorsRichard A. Gilmour, William A. Klaasen, William T. Motsiff
Life of this patent
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Abstract
The present invention relates to an alignment mark structure for laser fusing. An alignment mark structure is formed which is comprised of image elements that are placed on different film layers in a semiconductor device. Alignment is accomplished by examining the difference in reflected energy of a laser beam as the beam traverses the alignment mark structure. By forming the alignment mark structure such that it has elements on different film layers, the reflected energy can be modulated to avoid the situation in which no difference in reflected energy is found, which would make the alignment mark invisible to the laser fusing tool. A method of applying the alignment mark structure is also disclosed.
Claims33
A semiconductor device structure that acts as an alignment mark structure for laser fusing, wherein the alignment mark structure comprises two or more metal wiring layers, and wherein the alignment mark structure comprises at least one metal wiring layer formed with a damascene process.
A semiconductor device structure that acts as an alignment mark structure for laser fusing, the alignment mark structure further comprising:
- a characteristic fusing wavelength;
- a first metal wiring layer having at least one first wiring segment;
- a second metal wiring layer underlaying the first metal wiring layer and having at least one second wiring segment;
- and
- wherein said first wiring segment and said second wiring segment are separated by a distance equal to, or less than, one half the fusing wavelength.
A semiconductor device structure that acts as an alignment mark structure for laser fusing, wherein the alignment mark structure comprises two or more metal wiring layers, the alignment mark structure further comprising:
- a first metal wiring layer having at least one first wiring segment;
- a second metal wiring layer underlaying the first metal wiring layer and having at least one second wiring segment;
- and
- wherein the second metal wiring layer further includes a metal underplate.
A semiconductor device structure that acts as an alignment mark structure for laser fusing, wherein the alignment structure comprises a last metal wiring layer and a previous metal wiring layer.
A semiconductor device structure that acts as an alignment mark structure for laser fusing, wherein the alignment mark structure comprises two or more metal wiring layers, and wherein the two or more metal wiring layers comprise a stack.
A semiconductor device structures acts as an alignment mark structure for laser fusing, wherein the alignment mark structure further comprises at least one metal fuse link.
A semiconductor intergrated circuit device containing an alignment mark structure for laser fusing using a laser having a characteristic wavelength, said alignment mark structure comprising:
- a first metal wiring layer formed in a first layer;
- and
- a second metal wiring liver formed in a second layer, said second layer overlaying the first layer;
- and
- wherein said first metal wiring level and said second metal wiring level arm formed with a damascene fabrication process.
A system for aligning a semiconductor integrated circuit device for laser fusing, said system comprising:
- an alignment mark structure formed within at least two layers of said semiconductor integrated circuit device, said alignment mark structure containing at least one alignment mark and formed from a plurality of metal wiring layer segments distributed throughout said at least two layers and surrounded by a first material;
- a scanning device comprising a laser beam, said scanning device capable of targeting said laser beam at a surface of said semiconductor integrated circuit device beneath which said alignment mark structure is located;
- a device for determining the reflected energy from said alignment mark structure and said surrounding first material;
- a device for measuring a contrast level, from said reflected energy, between said alignment mark structure and said surrounding first material;
- a device for selectively guiding the scanning device to scan a different layer when said contract level is low;
- and
- a device for accurately determining the position of said alignment mark structure from said reflected energy.
A method of making an alignment mark structure for use with a laser fusing device, said method comprising the steps of:
- a) providing a substrate layer;
- b) depositing a base layer on said substrate layer;
- c) depositing a first layer on said base layer;
- d) forming a first metal wiring layer in said first layer;
- e) depositing a second layer on said first layer and first metal wiring layer;
- and
- f) forming a second metal wiring layer on said second layer;
- and
- wherein said first metal wiring layer and said second wiring layer are formed in segments.
Dependencies are inferred from the claim text.