Structure with realization of 3D interlayer vertical interconnection by using flexible substrate and manufacturing method thereof

Abstract

The invention relates to the technical field of electronic packaging and particularly relates to a structure with the realization of 3D interlayer vertical interconnection by using a flexible substrate and a manufacturing method thereof. The structure comprises a first printed circuit board, a second printed circuit board, a first device, a second device, a soldered ball and a lamination structure. The second device is installed above the second printed circuit board. The first printed circuit board is fixed above the second printed circuit board, and the second device is arranged in a groove. The first device is fixed above the first printed circuit board. The lamination layer covers the first printed circuit board, the second printed circuit board and the outer side of the first device. The soldered ball is arranged at the bottom of the second printed circuit board. The invention provides the structure with the realization of 3D interlayer vertical interconnection by using the flexible substrate and the manufacturing method, the discontinuity and impedance mismatching of signals can be reduced, thus the transmission rate of the signals is greatly improved, higher bandwidth is supported, and the interconnection density of the flexible substrate is higher.

Description

technical field [0001] The invention relates to the technical field of electronic packaging, in particular to a structure and a manufacturing method for realizing vertical interconnection between three-dimensional layers by using a flexible substrate. Background technique [0002] BGA (Ball Grid Array, printed circuit board with ball grid array structure) is an impedance discontinuity point on the signal interconnection. The size and shape of BGA affect the signal integrity of high-frequency transmission. The larger the BGA is, the more serious the discontinuity is, and the transmission loss increases at high frequencies, and the return loss also increases, which restricts the transmission of high-frequency signals, especially the transmission of radio frequency signals. With the decrease of BGA spacing, on the one hand, the risk of soldering is increased, causing short circuit, and on the other hand, the crosstalk between BGAs also increases, which affects signal integrity....

AI Technical Summary

Problems solved by technology

The larger the BGA is, the more serious the discontinuity is, and the transmission loss increases at high frequencies, and the return loss also increases, which restricts the transmission of high-frequency signals, especially the transmission of radio frequency signals.

With the decrease of BGA spacing, on the one hand, the risk of soldering increases, causing short circuits, and on the other hand, the crosstalk between BGAs also increases, affecting signal integrity

The spacing between BGA solder balls is standard, and according to different application standards, the property definitions of BGA solder balls are fixed, so it is difficult to use BGA to shield signals in three-dimensional packages.

Therefore, the shielding of the chip by the BGA is generally combined with an open cavity. Refer to the US patent US20020096767. Such an open cavity is better than a simple BGA shielding effect, but due to the existence of the BGA, it is possible to couple a certain amount of electromagnetic waves from the BGA, so the BGA The problems of signal discontinuity, signal crosstalk and signal attenuation are still difficult to solve

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