Semiconductior package substrate with embedded resistors and method for fabricating same

Abstract

A semiconductor package substrate with embedded resistors and a method for fabricating the same are proposed. Firstly, an inner circuit board having a first circuit layer thereon is provided, and a plurality of resistor electrodes are formed in the fist circuit layer. Then, a patterned resistive material is formed on the inner circuit board and electrically connected to the resistor electrodes to accurately define a resistance value of resistors. Subsequently, at least one insulating layer is coated on a surface of the circuit board having the patterned resistive material. At least one patterned second circuit layer is formed on the insulating layer and electrically connected to the resistor electrodes by a plurality of conductive vias formed in the insulating layer or plated through holes formed through the circuit board.

Description

FIELD OF THE INVENTION [0001] The present invention relates to semiconductor package substrates with embedded resistors and methods for fabricating the same, and more particularly, to a semiconductor package substrate having resistors embedded in a multi-layer circuit board and a method for fabricating the substrate, so as to provide good electrical performances for a semiconductor device using the substrate. BACKGROUND OF THE INVENTION [0002] Owing to the progress of semiconductor packaging technology and improvements in electrical performances for semiconductor chips, semiconductor devices are developed toward high integration. For example, a ball grid array (BGA) semiconductor device is characterized in that a plurality of array-arranged solder balls are formed on a bottom surface of a substrate and used as input / output (I / O) connections for electrically connecting a semiconductor chip mounted on the substrate to an external device such as printed circuit board (PCB). Compared to...

AI Technical Summary

Benefits of technology

"The present invention provides a semiconductor package substrate with embedded resistors and a method for fabricating the same. The substrate has a reduced size and increased flexibility, allowing for the incorporation of more passive components and improved circuit routability. The method includes steps of forming a patterned first circuit layer with resistor electrodes, applying a patterned resistive material to the layer, and forming a patterned second circuit layer on top of the resistive material. The substrate can also have plated through holes and conductive vias to connect the circuit layers to the resistors. The technical effects of the invention include improved accuracy in resistance value, reliability, and compact size of semiconductor devices."

Problems solved by technology

In accordance with high integration of the semiconductor device, more leads or contacts are required and also more noise is caused.

However, it is difficult to accurately control an applied amount of the solder paste 13, and the height of the solder paste 13 after being reflowed, as well as the surface flatness of the solder mask layer 12.

In a high-temperature environment during subsequent fabrication processes, the solder paste 13 would melt or become softened and leaks to the gap 15 due to capillary attraction, which causes bridging of the solder paste 13 applied on the two bond pads 11 and short-circuiting of the passive components 14, and thus adversely affects the production yield.

However, since the substrate has a limited surface area, a relatively large area occupied by the resistor would affect a layout of other circuits arranged on the substrate surface.

This thus reduces flexibility of circuit routability on the substrate, sets a limitation on the number of passive components that can be incorporated on the substrate, and does not facilitate the high integration development for the semiconductor device.

Furthermore, by the fact that the number of passive components to be incorporated is dramatically increased along with the requirement of high performances for the semiconductor device, if the foregoing method in which a semiconductor chip and a large number of passive components are simultaneously mounted on the substrate surface is employed, the size miniaturization for the semiconductor device can hardly be achieved.

However, in the foregoing structure, only the printing technique is used to form the dielectric layer 33 and the resistive layer 34 on the substrate 30, such that it is difficult to accurately control the capacitance and resistance thereof respectively.

Additionally, since the resistive layer 34 covers both the copper layer 32 and the dielectric layer 33 that are made of different materials, a reliability issue may be generated in a high-temperature and high-moisture environment during subsequent fabricating processes or tests, and thus electrical connection between the resistive layer and electrodes may also be affected.

However, the foregoing prior art only discloses that passive components can be mounted on the surface of the substrate but does not provide a strategy to apply passive components to a multi-layer package substrate in accordance with the requirements of high integration and size miniaturization for the semiconductor package.

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