Development of chip scale packages (CSP) for center pad devices

Author

Amagai, Masazumi ; Sano, Hiroyuki ; Maeda, Takayuki ; Imura, Takahiro ; Saitoh, Tadashi

Author_Institution

New Package Dev. Dept., Texas Instrum. Japan, Oita, Japan

fYear

1997

fDate

18-21 May 1997

Firstpage

343

Lastpage

352

Abstract

Memory chip scale package (MCSP) has been developed for center pad memory devices. The MCSP is classified into two designs, tapeless lead on chip (LOC) and flexible substrate, respectively. The MCSP with a tapeless LOC design consists of a polyimide-deposited chip which is bonded to a lead frame and then encapsulated with a molding compound. The MCSP made with a flexible substrate consists of a polyimide-deposited chip which is bonded to the flexible substrate with a thermoplastic polyimide and subsequently encapsulated with a liquid epoxy compound. Wire bonding technology was used for both of MCSPs. A 52 ball package are composed of solder balls (1.0 mm in diameter on a 1.27 mm pitch) attached to either the lead frame or the flexible substrate. The optimum material properties, the wafer fabrication and packaging process parameters, and the experimental and simulated reliability and performance results of the MCSPs are presented

Keywords

integrated circuit packaging; integrated memory circuits; bonding; center pad device; encapsulation; flexible substrate; lead frame; liquid epoxy compound; memory chip scale package; molding compound; polyimide-deposited chip; reliability; solder ball; tapeless lead on chip; thermoplastic polyimide; wafer fabrication; wire bonding; Atherosclerosis; Bonding; Chip scale packaging; Lab-on-a-chip; Lead; Polyimides; Protection; Ultra large scale integration; Wafer scale integration; Wire;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 1997. Proceedings., 47th

Conference_Location

San Jose, CA

ISSN

0569-5503

Print_ISBN

0-7803-3857-X

Type

conf

DOI

10.1109/ECTC.1997.606191

Filename

606191