October 2012

Doc ID 12282 Rev 5

1/17

AN2348

Application note

IPAD™, 400 µm Flip Chip:

package description and recommendations for use

Introduction

This document provides package and usage recommendation information for 400 µm pitch

Flip Chips. For information on 500 µm Flip Chips, see Application note AN1235.

The competitive market of portable equipment, notably the mobile phone market, is driven

by a challenging development of highly integrated products. To allow manufacturers of

portable equipment to reduce the dimension of their products, STMicroelectronics has

developed packages with reduced size, thickness and weight in the form of the Flip Chip.

The electrical performance of such components in Flip Chips is improved thanks to shorter

connections than the ones in standard plastic packages (such as TSSOP, SSOP or BGA).

Figure 1.

Typical Flip-Chip packages

The Flip-Chip package family has been designed to fulfill the same quality levels and the

same reliability performances as standard semiconductor plastic packages. This means

these new Flip-Chip packages should be considered as new surface mount devices which

will be assembled on a printed circuit board (PCB) without any special or additional process

steps required. In particular this package does not require any extra underfill to increase

reliability performances or to protect the device. This package is compatible with existing

pick and place equipment for board mounting. Only lead-free, RoHS compliant Flip Chips

are available in mass production.

This application note addresses the following topics:

1

2

3

4

5

E

D

C

B

A

1

A

B

Multi-bump

2-bar

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