The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 11, 1989
Filed:
Apr. 18, 1988
Francine Y Robb, Tempe, AZ (US);
F J Robinson, Scottsdale, AZ (US);
Bridget Svechovsky, Phoenix, AZ (US);
Thomas E Wood, Chandler, AZ (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
Filled trenches useful in semiconductor devices for isolation or other purposes are provided by etching a trench in the semiconductor substrate, lining the trench with a first material (e.g., silicon dioxide), covering the first material with a seed layer (e.g., polysilicon) for nucleating a further material, removing a part of the seed layer on the first material in an upper part of the trench, and then filling the trench by selectively depositing the further material (e.g., polysilicon) on the remaining seed layer. Thermally grown silicon dioxide is convenient for the first material. The first material and seed layer may extend over the substrate surface. The upper portion of the seed layer is conveniently removed by first covering the seed layer with a mask (e.g., photoresist) and then etching back the mask to expose the seed layer above the substrate surface and in the upper portion of the trench, leaving part of the mask in the lower portion of the trench. The exposed portion of the seed layer is then etched away. The remaining portion of the mask is removed before growing the trench filling material on the remaining part of the seed layer in the trench.