MultiChip Mems sensor packaging

In consumer applications the size and cost of the package are becoming increasingly important especially in the applications for the user interface for Gaming and Mobile telephones. The initial adoption of accelerometer devices has enabled human movement to become part of the man machine interface, simply tilting the device to change menu or navigate a web page. One of the key factors in the adoption of the accelerometer devices was the development of LGA style packages which opened up these new market segments to MEMS devices by the use of a low cost, low stress flexibile platform, adaptable to different form factors and chip dimensions. Recently following on from the success of accelerometer devices Gyroscopes devices are increasingly being adopted to add dynamic angular movement sensing putting two different sensors in different packages. In addition to these devices, digital compasses or magnetometeters and altimeters are now being introduced to include directional and height sensing functions. Increasing therefore more than one sensor is used within the same hand held device and instead of using separate device there is now a requirement for Multichip LGA based MEMS Packages. These packages must take into account the particular devices constraints of each individual device within the same package. The individual assembly building blocks for the various device requirements are described in detail, in particular the development of novel assembly techniques for 90° chip mounting and interconnection is outlined. The design of such packages is outlined and the problems encountered in packaging multiple MEMS devices in this style of package structure discussed.