Inflatable bladder with suction for supporting circuit board assembly processing

Abstract

An inflatable bladder comprising at least one aperture and / or at least one baffle within the bladder for supporting a printed circuit board during component placement on a semiconductor substrate such as a printed circuit board is provided. The inflatable bladder is positioned to provide support for the substrate while apertures within the inflatable bladder communicate a suction force to the substrate to inhibit the substrate from bending, bowing, or flexing away from contact with the inflatable bladder during component placement. The inflatable bladder provides support for the substrate while attempting to prevent injury to components by pliably conforming to component irregularities on the back side of the substrate. The inflatable bladder can be selectively inflated or deflated for contacting the substrate and thereafter supporting the back side of the substrate during assembly operations. Alternatively, a lift table can be selectively raised or lowered for placing the inflatable bladder in contact with the back side of the substrate during assembly operations. The inflatable bladder can contain one or more baffles to define one or more compartments within the inflatable bladder. The inflatable bladder can be incorporated into a typical system for component assembly comprising a pair of rails, each having a slot therein, for receiving a substrate.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application is a division of U.S. patent application Ser. No. 10 / 000,510, filed Oct. 23, 2001.FIELD OF THE INVENTION [0002] This invention relates in general to semiconductor device assembly processing and, more particularly, to an inflatable bladder for supporting and securing a semiconductor substrate during a component placement process. BACKGROUND OF THE INVENTION [0003] Various techniques have been developed for the automated mounting of electronic components to printed circuit boards (PCB's). During mounting, substantial forces can be exerted on the PCB by the automated placement head. Accordingly, assembly processing requires back side support of a chosen substrate, such as a circuit board, capable of withstanding such forces. The back side support should provide good, solid support for allowing even and accurate placement of components on the top side of the substrate. Good support is needed where fine-pitched component lead...

AI Technical Summary

Benefits of technology

[0016] In another embodiment, the method further comprises preventing the semiconductor substrate from bending, bowing, or flexing away from contact with the inflatable bladder during component placement. In yet another embodiment, the method further comprises expelling the supply of fluid from the inflatable bladder such that the inflatable bladder deflates, and thereafter, transporting the semiconductor substrate to a subsequent step in the semiconductor assembly process. The method can also comprise adjusting the suction force introduced into the aperture(s) to permit the suction pressure to be increased or decreased. Further, the method may include segregating the cavity within the inflatable bladder using the baffle(s) and thereby creating separate chambers within the inflatable bladder. By incorporating an aperture, check valve, or like device into the baffle(s), the baffle(s) can permit distribution of the suction force within the chambers such that the suction force in the chambers is approximately equal.

Problems solved by technology

Further, the bladder in Thompson is limited to a sole air compartment or chamber.

Among other drawbacks, support provided by the bladder can be uneven and cause injury to the PCB or components.

Also, with a sole chamber, Thompson is limited to a single internal pressure within the air bladder.

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