Thin Film Ceramic PCB
The "Thin Film" refers to the thinner thickness of conductor layer on Ceramic PCB, comparing with "Thick Film Ceramic PCB". Normally the thickness of thin film Ceramic PCB will be less than 10 micron (10 um). That thin film was paurting on ceramic substrate/core.
In the same substrate using evaporation, sputtering, electroplating process, and other thin film manufacturing technology to produce passive network, and assemble on micro-components, devices separately, plus the hybrid integrated circuit formed by packaging.
According to the components parameters concentration and distribution situation in passive network, thin film ceramic PCB is divided into lumped parameter and distributed parameter. The former applies to low-frequency to microwave band, and later only applies to the microwave band.
|Characteristics of Thin Film Ceramic Board|
Compared to thick-film ceramic PCB, the major characteristics of thin-film circuits is the smaller size. However, the manufacturing equipment used is more expensive and the cost of production is higher.
Thin-film Ceramic PCB is suitable for a variety of circuits, especially for analog circuit which need high accuracy, great stability, and excellent performance. Compared with other circuits board, it is more suitable for microwave circuits.
|Thin Film Ceramic Board Manufacturing Method|
There’re a number of ways to produce thin film layer, such as the normal physical vapor deposition (PVD), and less popular anodic oxidation or electroplating.
In the physical vapor deposition (PVD) method, the most commonly used are evaporation process and the sputtering process. Both two processes are carried out in a vacuum chamber, therefore, so they are called by a joint name as “vacuum film-forming method”. Using these two methods, passive components, interconnects trace, insulation film and protective film can be produced in passive network.
Using anodic oxidation method, a dielectric film can be produced and resistance value of film resistor can be adjusted.
In manufacturing microwave hybrid integrated circuits, electroplating method can be used to increase the thickness of thin-film micro-strip line, in order to reduce power consumption.