Cofired Ceramic (HTCC)

THE HIGH TEMPERATURE COFIRED CERAMIC (HTCC) PROCESS

High Temperature Cofired Ceramic (HTCC) technology is a perfect match for the increasingly complex micro-electronics and opto-electronics packaging designs used in harsh environments.


Why HTCC?

This material is popular for hermetic packages due to:
  • its electrical properties (low electrical conductivity & low thermal conductivity), giving it good insulation capabilities
  • high mechanical strength, hardness and subsequent durability
  • thin multi-layer structure with metal vias enabling a high-density interconnect, making it possible to miniaturize designs (similar to HDI vs. conventional PCBs in the printed circuit world)
  • superior hermetic performance, especially under extreme heat, cold or pressure. - very high frequency capabilities making it ideal for high-speed data transmission networks (high frequency, high output).
  • lower weight density than Kovar, a key advantage for applications where weight matters (payload...)
  • Superior brazing capabilities, enabling Egide to braze various metallic components (frame, heatsink...) or glass components (window, lens...) in order to assemble packages with complicated shapes

Egide HTCC expertise

Egide handles in-house all the development & manufacturing of its proprietary HTCC technology, from the ceramic powders to the final components. The conductive inks are also developed and made internally.

The main steps of the manufacturing process are:



Figure 1: ceramic manufacturing process flow


The HTCC production and R&D activities are fully integrated at our Bollène (France) and at our Cambridge, MA (USA) sites.

Figure 2: ceramic CSP package



Figure 3: 10x10 QFN RF standard package (frequency range up to 43GHz)




Figure 4: Ceramic and metal connector for an IR camera 




HTCC vs. LTTC:

LTCC stands for low temperature cofired ceramics. Glass-like materials are added to the ceramic paste before being co-fired at 950°C (HTCC is co-fired at 1600°C).

  • HTCC is more advantageous than LTCC in high-power packaging areas with high requirements for thermal stability, substrate mechanical strength, thermal conductivity, hermeticity, and reliability.
  • LTCC, because of the low dielectric constant and high-frequency low loss properties of glass-ceramics, is in general more suitable for applications with RF, microwave and millimeter-wave devices, with the constraint that LTCC is mechanically less strong than HTCC.


HTCC vs. Glass-to-metal-sealing (GTMS)

One major advantage of HTCC vs. GTMS is the ability to use the multilayer structure of the ceramics as if it was a printed circuit board (PCB) with a high routing density.

Each ceramic layer can be used as a solid metal plane for power, ground, IOs, differential signal pairs, layers being connected with vias, all of this in an hermetic and more durable and reliable material than GTMS.

 You will find more information on our ceramic design guidelines here.