Alignment for backside illumination sensor
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsJen-Cheng Liu, Dun-Nian Yaung, Shou-Gwo Wuu
Life of this patent
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Abstract
An apparatus and manufacturing method thereof, wherein an integrated circuit is located in a first region of a substrate having first and second opposing major surfaces, and wherein an alignment mark is located in a second region of the substrate and extends through the substrate between the first and second surfaces. The alignment mark may protrude from the first and/or second surfaces, and/or may comprise a plurality of substantially similar alignment marks. The second region may interpose the first region and a perimeter of the substrate. The second region may comprise a scribe region.
Claims14
A method of forming an alignment mark, comprising:
- forming a recess in a first substrate, wherein the first substrate includes first and second opposing major surfaces, wherein a plurality of transistors are located in a first region of the first surface, and wherein forming the recess includes forming the recess in a second region of the first surface;
- filling the recess with a material;
- planarizing the material within the recess;
- coupling the first substrate to a second substrate such that the first surface of the first substrate is closer to the second substrate relative to the second surface of the first substrate;
- and
- thinning the first substrate by planarizing the second surface of the first substrate at least until the material in the recess is exposed.
A method of forming an alignment mark, comprising:
- depositing a first layer over a first substrate;
- forming a first aperture in the first layer;
- etching the first substrate through the first aperture to form a first recess extending into the first substrate to a first depth;
- forming a second aperture in the first layer;
- etching the first substrate through the second aperture to form a second recess extending into the first substrate to a second depth, wherein the second depth is substantially less than the first depth;
- filling the first and second recesses with a material;
- planarizing the material in the first and second recesses;
- depositing a second layer over the planarized material in the first and second recesses;
- coupling the first substrate to a second substrate such that the first and second substrates are separated by at least a portion of at least the second layer;
- and
- thinning the first substrate by planarizing a backside surface of the first substrate at least until the material in the first recess is exposed.
Dependencies are inferred from the claim text.