Browse Prior Art Database

New method of tape cutting & package loading for conformal EMI shield

IP.com Disclosure Number: IPCOM000250237D
Publication Date: 2017-Jun-15
Document File: 2 page(s) / 264K

Publishing Venue

The IP.com Prior Art Database

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 76% of the total text.

New method of tape cutting & package loading for conformal EMI shield

Description

The existing method is having the package loaded on the pocket tape prior to EMI

(Electromagnetic Interference) sputtering process. However, it is prone to the limitation of

package placement offset. A high variation in tape edge to ball edge gap of either one of the

package side as indicated in Figure 1A would result in the exposure of package edge, which

instigated potential risk of package side discoloration due to the EMI material seeped through

the sidewall and underneath package during sputtering process. The gap between package

edge to ball edge requires 150um as minimum clearance for the pocket tape to appropriately

covering and protecting the package side denoted as tape edge to package edge as shown in

Figure 1B.

This invention is disclosing tape edge cutting methods by laser to increase the EMI shield

process capability for BGA package with narrower package edge to ball edge, literally means

tape edge to package edge as 50um minimum gap of edge cut. Having said that, there is a

complete tape coverage from package edge to ball edge, which are presented in respective

Figures 2A (bottom view) and 2B (side view) for Type 1 laser cutting on tape from ball edge

to ball edge as the tape edges, while Figures 3A (bottom view) and 3B (side view) for Type 2

laser cutting on tape from ball center to ball center as the tape edges.

Prior Arts

Figure 1A: Pocket Tape - Figure 1B: Pocket Tape -

No Ed...