Flex Circuits

Introduction

Nitto Denko specializes in designing and fabricating flexible printed circuits from single sided to multilayer constructions. The materials used in fabrication of FPC are conventional (adhesive based) as well as adhesive less with various layer thicknesses available with each material configuration.

Flexible printed circuits for disc drive applications

As the disc drive performance becomes ever more demanding in terms of data access speed, transfer rates, and data reliability the interconnect products must be designed to meet the challenges of the future HDD performance requirements.

Nitto Denko offers two distinct type of products for HDD applications, read/write actuator flex circuit as well as Circuit Integrated Suspension (CIS). The two different types of interconnect products are optimized to perform very different mechanical functions in the drive.

Actuator Flexible Printed Circuit

The Actuator FPC is designed to meet the flex fatigue life challenges of 100’s of Million actuator cycles at very tight bend radii. As the motor speeds inside the drive increase beyond 7200 RPMs, the operating temperature temperatures inside the drive also increases which can negatively impact some conventional types of adhesives resulting in significantly reduced flex fatigue life. Nitto has designed a new generation of adhesives to meet this challenge. Our proprietary adhesives technology can enhance the performance of next generation drives.

CIS

Our proprietary CIS technology enables us to design suspension circuits that provide impedance matching between the magnetic heads and preamplifier chip. Nitto uses TDR to validate our circuit simulations to ensure state of the art performance. The core of our technology is the proprietary patented photosensitive polyimide material coupled with semi-additive metallization process. Suspension blanks are custom designed, our customers can dial in a wide range of material thicknesses to optimize the stiffness of the HGA. Nitto’s materials can offer some of the lowest stiffness available in the gimbal area. This ensures compliance of the head to the media flight height.

Flexible Printed circuits for Chip Scale Packages

Evolution in the packaging technology has created new opportunities for the flexible printed circuits. With our semi-additive process we can manufacture very fine pitch carrier flex to meet ever increasing number I/Os per device. The carrier flex comes in two basic configurations single sided for TBGA with 300-400 I/Os and double sided for

Devices with a number of I/Os exceeding that.

Services

Nitto Denko America offers design services, quick turn around times on prototype orders as well as electrical testing of the substrates. Nitto Denko’s customer philosophy is to build long term relationships based on trust and sincerity. We strive to become our customer’s partners, working together to achieve our customer’s objectives. We would appreciate the opportunity to work with you to help you design the interconnect product that will exceed your expectations in terms of quality, on time delivery, reliability and pricing.