Atsuyuki Fukano

US Patent:

6453458, Sep 17, 2002

Filed:

Jul 9, 1999

Appl. No.:

09/351203

Inventors:

Atsuyuki Fukano - Addison TX
Zhiqiang Feng - Nagareyama, JP
Hideki Koide - Tokyo, JP

Assignee:

Ball Semiconductor, Inc. - Allen TX

International Classification:

G06F 1750

US Classification:

716 21, 700121, 700120, 700 98, 430 5, 378 35

Abstract:

The present invention provides a method for segmenting and mapping a two-dimensional conventional circuit pattern to a flat mask for projection onto a three-dimensional surface. The circuit pattern is first segmented into a plurality of circuit segments enclosed in a plurality of base units of an imposed grid system. Subsequently, locations and the boundary conditions for a plurality of mask segments on the mask are determined such that no unneeded overlapping at the boundaries of the projected image on the spherical shaped semiconductor device is possible. The mask, along with a photolithography system having a plurality of mirrors, projects the circuit pattern onto the spherical shaped semiconductor device.

US Patent:

62517651, Jun 26, 2001

Filed:

Jul 8, 1999

Appl. No.:

9/350041

Inventors:

Atsuyuki Fukano - Addison TX
Nobuo Takeda - Richardson TX

Assignee:

Ball Semiconductor, Inc. - Allen TX

International Classification:

H01L 2144

US Classification:

438612

Abstract:

A system and method for forming solder bumps on a surface of a semiconductor device, such as a spherical-shaped semiconductor integrated circuit, is disclosed. Multiple devices are first aligned so that a vacuum chuck can hold all of the devices with an appropriate orientation. The vacuum chuck can then dip the devices into different molten metal compounds to form a plurality of solder bumps. Metal solder materials of different melting points are chosen so that the thickness of the solder bumps are partially controlled by the number of layers of solder metal sequentially grow on the metal pads. Once the solder bumps are grown on the devices, the vacuum chuck can immediately transfer the devices to a tape and reel assembly for further transportation thereof. It can also be easily fed into a tube assembly which protects the spherical shaped semiconductor device with the solder bumps during the shipping process.