General BGA/CSP Reballing Process

The following describes the general methodologies used by BEST for reattaching solder balls to either BGAs or CSPs as part of its BGA rework services. The two methodologies described herein are used by BEST Inc in the reattachment of solder balls to a variety of area array devices. These reballing methods include:

• StencilQuik™ Stencils
• EZReball™ Solder Preforms

The materials and tools required for each of the methods as well as critical elements of the reballing operation are detailed in the following pages specifically and are outlined more generally in the IPC Rework and Repair Procedures of IPC 7711. The experience BEST has gained in tens of thousands of devices on hundreds of different pattern configurations, body styles and package materials has shaped the information found in these process descriptions. While several device manufacturers do not recommend the reballing of their devices due to the number of thermal cycles the devices themselves have to go through in the reballing process, BEST has successfully attached solder balls to every major device type. This has saved BEST customers from having to spend hundreds of thousands of dollars in component acquisition costs or made available devices which are difficult to obtain in times of allocation thereby allowing the end customer to meet mission critical delivery times.

	BEST Reballing Methods Each of the reballing methods used by BEST Inc. is equal in its outcome -the precise reattachment of solder balls onto area array devices. The type of method chosen is determined by several criteria including: The lead-time requirements of the customer The availability of materials for each of the 2,000 plus known grid array patterns including the solder ball diameter and alloy
General BGA/CSP Reballing Process Handling of BGAs StencilQuik™ Fixturing Technique Solder Preform Technique Dry Packaging Ceramic Package Reballing Reballing Challenges Optional Services