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:
Mar. 08, 2005
Filed:
Oct. 22, 2002
Christopher J. Summers, Dunwoody, GA (US);
Hisham Menkara, Mableton, GA (US);
Bee Yin Janet Chua, Penang, MY;
Christopher J. Summers, Dunwoody, GA (US);
Hisham Menkara, Mableton, GA (US);
Bee Yin Janet Chua, Penang, MY;
Agilent Technologies, Inc., Palo Alto, CA (US);
Abstract
The present invention provides a process and apparatus for selectively depositing materials on a semiconductor device, such as depositing phosphors or other optical materials on a light emitting diode (LED), using an electrophoretic deposition process. The semiconductor device comprises a p-side and an n-side. A first biasing voltage is applied between an anode and the p-side of the semiconductor device. A second biasing voltage is applied between the p-side and the n-side of the semiconductor device. The relative biasing of the p-side and the n-side determines where coating is deposited on the semiconductor device. An optional pre-coating process is used to deposit a high resistivity dielectric material, such as silica, on the semiconductor device. The pre-coating can even the electric field on the surface of the semiconductor device, where local features such as metal connections or passivation layers disturb the electric field during phosphor deposition without pre-coating.