Clad Metals for CTE in Electronic Packaging

The Property of Clad Metals for CTE in Electronic Packaging
    Now we have devised and manufactured such clad metals to meet all kinds of demands including CIC (Cu/Invar/Cu) and CMC (Cu/Mo/Cu) which are the most popular in applications. All of them are composed of low thermal expansion coefficient material and high heat conductivity material through metallurgical bonding. Excellent bonding strength integrated each component's advantage. Also the thermal expansion coefficient and heat conductivity of clad metals can be adjusted by changing the cladding ratios. Besides the above virtues, lower cost of some clad metals is also attractive to users. So clad metals always are taken into consideration in electronic packaging.
    The properties of the example clad metals and traditional heat sink material Mo are described in table 1. From the table, it is shown that the properties is almost equivalent between CIC-1 and Mo. And the advantages of lower gravity, easier shape deforming and plating Ni or Sn well make it possible to be widely used for heat spreader, chip to chip's interconnector, lead frames, hybrid circuit case bottoms and MCM cape in power semiconductors such as SCR, transistor module, SSR and IC packaging fields. The another reason that we specially recommend CIC-1 is lower cost than Mo.

Table 1 The Properties of Clad Metals for CTE in Electronic Packaging

Notes:
1) To the CIC-1 and CMC, the thermal expansion coefficient, the heat conductivity and
   mechanical properties can be adjusted according to the requirement.
2) It refers to the direction of parallel to the surface. In addition we have designed the
   special CIC which has higher vertical heat conductivity of more than 100 v/m.℃.

The shapes we supplied
   Commonly we supply coils of clad metal for users who have punch equipment themselves. And pieces of parts are also available if users require.