Thick film circuit fabrication is made using a print & fire (P+F) technique. This involves a combination of multi-layer screen printing of precious and semi-precious metals (Au, Ag, Pd), as well as the firing of tracks and precision resistors onto a range of ceramic and metal substrates. Surface mount components and bare die components with wire bonding can also be incorporated, and optional full encapsulation provides greater environmental protection. The use of different pastes allows the production of conductive tracks as well as resistors, which can be custom specified and then laser-trimmed to a high level of accuracy, offering an exact choice of value so that no compromise in design is necessary.
What Are Thick Film Hybrids Used For?
Thick film hybrid circuit board are ideal for environments where a high level of reliability is needed as they can withstand a much wider temperature range and have higher durability than conventional PCB assemblies. Thick Film technology is used extensively in aerospace, defence, and automotive applications. However, its durable and reliable nature is starting to appeal to a broader market. As an experienced company in this technology, we are the perfect partner to develop and manufacture thick film circuit boards to suit any application.
What Are the Benefits of Thick Film Hybrids?
Ceramic substrates provide several key advantages over standard FR4 based PCBs. One of the primary advantages is their thermal conductivity. For example, Aluminium Oxide (Alumina) offers an increase in thermal conductivity of approximately 20 times that of FR4, and Aluminium Nitride offers an increase of approximately 100 times. Another advantage of ceramic substrates is that they offer extremely low thermal expansion properties. This makes them ideal for use in harsh environments where extremes of temperature are likely. The combination of low thermal expansion and high thermal conductivity ensures that not only is thermal expansion limited, but it is also evenly spread across the board, limiting the possibility that large amounts of stress will be exerted in specific areas.
They manufacture thick-film circuits in small to medium quantities in-house and thus offer maximum efficiency in the manufacture of hybrid modules. Especially for the miniaturization of electronics, there are hardly any alternatives to ceramic multilayer circuits. Hybrid circuits produced with thick-film technology are equipped with electronic components using different manufacturing techniques. The ceramic substrates used are low-loss insulators and resistant circuit carriers.
They use modern screen-printing machines for the application of resistors, conductor paths, contact systems, and multi-level wiring carriers. They achieve special precision of the resistance value through active and passive laser alignment. Glazes and protective lacquers can also be applied by screen printing to protect the circuits.
During laser trimming, resistors in our thick-film circuits and on integrated circuits are adjusted to the exact resistance value (passive adjustment) or the function of the circuit (active adjustment). During the trimming process, the respective output signal is constantly measured and compared with the nominal value. When the target value is reached, the laser cut is automatically stopped.