Electro Ceramic Products

Glass-to-metal seals are produced via an effective production process comprised with only three involved pieces: the metal components, metal pin or lead frame, and glass preform. In order to attain the desired conditions of the final assembly, knowledge of the fundamental details is critical. Competence in glass types and formulations is a key expertise in maximizing robustness and reliability, especially when it comes to customized components. It also includes the selection of the right metal and glass combination for the intended end-use and proper execution of the sealing process to maximize the integrity of the seal. Electro Ceramic Industries in-house development capability to modify or engineer entirely new glass types allows us to fulfill unique challenges and create new applications.

The CTE of glass and metal in matched seals is balanced. Matched seals are typically used for applications where high-temperature variations are present, or tight pin pitch or dimensional requirements (for example, miniaturized or non-round shapes) are factors. Depending on the design, matched glass-to-metal seals are able to maintain integrity through tens of thousands of thermal cycles and are well suited for semiconductor and optoelectronic assemblies where structural integrity is essential for precise operation of the enclosed electronics.

Due to vastly different CTEs of glass and metal in compression seals, the outer metal eyelet shrinks firmly onto the sealing glass during the production process. This compressive force forms a seal with immense bonded physical strength. In fact, the compressive strength of glass is ten to twenty times higher than its tensile strength. This is why compression seals are typically used for designs with requirements for high mechanical robustness. Usage examples can be found in automotive and energy applications, where long-term seal integrity is essential for continued safe operation of electronics involatile environments.

Glass-to-metal seals are engineered to perform reliably in harsh operating conditions, such as extreme temperatures, moisture, pressure or chemicals. They can also fulfill requirements for long life, performance, and efficiency improvements, as well as innovative designs. The primary function of glass-to-metal seals is to enable reliable connection and protection for the manufacture of high quality and long-lasting hermetically sealed components or equipment. Flexibility is a key characteristic of glass-to-metal sealing technology. This is demonstrated by the multitude of functions, designs, and sizes of GTMS components in a broad range of applications.

ECI’s experts can utilize decades of experience to guide customers to exactly what will work and provide solutions to maximize effectiveness in their application. The ECI team has extensive experience in manufacturing power packaging, including high thermal dissipation power packages and power transistor outline packages. Typical applications include power converters, motor drives, switch mode power supplies, power hybrid circuits, and power thrusters for military, aeronautic and space applications. Utilizing either glass to metal seal (GTMS) or ceramic to metal seal (CTMS) feed thru technology, they are available as standard product form types (TO-254, TO-257, …) or custom designed to meet your needs. We can produce your power package with glass or ceramic seals, and a variety of materials.  We are also always reviewing and analyzing new materials that will help solve your thermal challenges. A range of molded glass-ceramic flatpacks is in development. Typical end products include microwave and RF devices.

Electro Ceramic Industries Recommends Direct Bond Copper for Demanding Thermal Management Applications

Electro Ceramic Industries/ ECI offers cost effective and rapid turnaround Direct Bond Copper(DBC) products on Alumina and Aluminum Nitride. Direct Bond Copper (DBC) is a widely acceptable and a long-proven technology for power electronic products due to its high thermal conductivity, high current capacity and heat dissipation of the high-purity copper on ceramic. DBC is the direct mating of two dissimilar electronic materials (Copper and Ceramic). The interface between the pure copper and the ceramic is very reliable. The process takes advantage of the copper – oxygen eutectic where the melting point is lower than that of pure copper or oxide ceramic. At the melting temperature the eutectic is the only liquid present, it wets and bonds to both surfaces.

Utilizing various copper and ceramic thickness and ceramic type makes it is feasible to affect a resulting CTE value of total system to avoid a CTE mismatch with different semiconductor devices. The standard Direct Bond Copper or DBC technology which uses copper foil thicknesses in the range of 0.005 to 0.020inches. It is best utilized where the large geometry requirements of 0.015 inch wide lines and spacing scan be used.

Direct bond copper (DBC) substrates are comprised of a ceramic isolator, Al 2 O 3  (aluminium oxide) or AlN (aluminium nitride), onto which pure copper is bonded in a high temperature melting and diffusion process. The great heat conductivity of Al 2 O 3  (24 W/mK), AlN (180/230 W/mK) and HPS (28 W/mK), as well as the high heat capacity and heat spreading provided by the thick copper layer (200 - 600 µm),make Electro Ceramic Industries ceramic substrates irreplaceable in power electronics.

The coefficient of thermal expansion of Al 2 O 3  (7.1 ppm/K) and AlN (4.7 ppm/K) is close to that of silicon(4 ppm/K). Therefore, DBC is a suitable substrate for durable packaging of bare dice since such assemblies are not likely to fatigue during the product life.

ECI has developed a proprietary process that provides it with the unique ability to braze metal gull wing leads and other configurations to DBC. The strength of the copper bond to ceramic is subject to delamination at high temperatures and reducing atmospheres. ECI’s process does not degrade the bond and allows for more expansive designs.

ECI is your Direct Bond Copper source for all of your demanding thermal management applications. The entire ECI teams looks forward to the prospects of becoming a supplier to your organization.