A method for manufacturing a multi-step cavity on an ltcc substrate

Abstract

The invention discloses a manufacturing method of a multi-step cavity on a LTCC substrate. A cavity structure is decomposed. According to different thicknesses of steps, raw ceramic chips which have different layers and are provided with corresponding holes are used to carry out superposition respectively. First lamination is performed on the raw ceramic chips which form each step through superposition and a substrate pedestal respectively so as to form each independent raw ceramic base. Each raw ceramic base forming the step is successively superposed on a raw ceramic base of the substrate pedestal and a soft silica gel which can cover the holes is placed on an uppermost layer of the raw ceramic base. Then, second lamination is performed so as to form the LTCC substrate. After the second lamination, the soft silica gel is removed. By using a method technology of the invention, an operation method is simple; a condition that a cavity die size or a sacrificial layer material size is calculated according to different cavity sizes is not needed; the soft silica gel can be used repeatedly, a metal die does not need to be manufactured or a sacrificial layer material does not need to be used and cost is saved; the method is especially suitable for manufacturing the multi-step cavity with an irregular shape and a complex structure.

Description

technical field [0001] The invention relates to a method for manufacturing a cavity on an LTCC substrate, in particular to a method for manufacturing a multi-step cavity on an LTCC substrate. Background technique [0002] LTCC (Low Temperature Co-fired Ceramics) substrate has remarkable characteristics such as high three-dimensional wiring density, embedded integrated components, good high-frequency transmission performance, strong environmental adaptability, and high long-term reliability. It has become a typical advanced substrate for modern microelectronic components. Multilayer interconnection LTCC substrates with cavities are high-performance and high-density components such as 3D-MCM (three-dimensional multi-chip components), SIP (system-in-package), MEMS (micro-electromechanical systems) devices, and T / R (transmit / receive) components. Integrate the important components of the product, which not only makes the assembly and packaging density of the product higher, but a...

AI Technical Summary

Problems solved by technology

This method has the following disadvantages: 1) Each circuit needs to process a set of metal mold and laminated cover plate, the metal mold is used to make the silicone body, and the laminated cover plate is used to restrain the expansion of the silicone body

This method has the following disadvantages: 1) The size and thickness of different cavity plugs need to be calculated separately. When the size of the cavity plug is too large, the sintering curve needs to be adjusted in order to completely volatilize the sacrificial layer material during co-firing of the LTCC substrate; 2) when When the thickness of the sacrificial layer plug is greater than 0.5m, it is difficult to completely volatilize the sacrificial layer green porcelain, and some unburned sacrificial layer material residues will remain on the conductor surface in the cavity of the LTCC substrate after co-firing

The residue is wrapped by the glass inside the LTCC green ceramic sheet during the co-firing process, and it is difficult to remove after sintering, which will affect the bonding, bonding and other processes in the cavity

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