05239448 is referenced by 224 patents and cites 20 patents.

A method of reducing the area of MCMs that are integral to a flexible carrier is provided. A locally complex area, i.e. multilayer MCM carrier is constructed on a flex carrier, along with other components to form a subsystem. The flex carrier provides the interface between the MCM and the system that is utilizing the function. Also, the flex carrier will receive non-complex portions of the function, e.g. low I/O devices, not required to be mounted on the complex area (MCM) of the subsystem. The locally complex functional area will contain the high performance DCA mounted components, such as custom ASICs, processors, high frequency analog parts and other high I/O chips. The MCM on flex is constructed by obtaining an appropriate flexible carrier, such as a dielectric material having electrically conductive signal lines circuitized on both sides. A photoimageable dielectric layer is then placed over the appropriate portion of the circuitized carrier and vias are formed therein and filled with electrically conductive material. The top side of the dielectric layer is then circuitized and electrically connected to the flex carrier wiring layers as required. Additional layers are then built as needed by an identical process. Electrically conductive pads are formed on the top circuitized dielectric layer in order to provide an interconnection point for the chip I/Os that will be directly attached thereto.

Title
Formulation of multichip modules
Application Number
7/783644
Publication Number
5239448
Application Date
October 28, 1991
Publication Date
August 24, 1993
Inventor
Gustav Schrottke
Austin
TX, US
Charles T Perkins
Austin
TX, US
Agent
Mark E McBurne
Assignee
International Business Machines Corporation
NY, US
IPC
H05K 1/14
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