Lead-free auto power MOSFETs come in standard TO packages

Infineon Technologies has introduced automotive qualified 100% lead-free power MOSFETs for TO package types. Based on the combination of packaging technology and Infineon’s thin wafer process technology, the new 40V OptiMOS™ T2 power MOSFETs offer high-performance specifications.

The company uses a diffusion soldering die attach approach to produce the lead-free packages that include TO-220, TO-262, and TO-263. Because of specific requirements in terms of package geometry, die pad thickness, and chip size the diffusion soldering die attach approach is today only suitable for these three package types, says Infineon. OptiMOS T2 products in these packages are ready for production.

With the new MOSFET series, Infineon says it exceeds current RoHS (Restriction on Hazardous Substances) directives related to lead-based solder used to attach silicon chips to packages. Stricter ELV RoHS directives pending implementation after 2014 may require 100% lead-free packaging. The new Infineon devices allow customers to meet these stricter requirements.

The Infineon-patented lead-free die-attach uses a diffusion soldering approach, which allows improved electrical and thermal performance, manufacturability, and quality. By matching this die attach technology with Infineon’s thin wafer processes (60 µm compared to standard 175 µm), the company says this enables several improvements for power semiconductors:

• The technology is environmentally friendly as no use of lead or other toxic material is involved.
• Through the combination of diffusion soldering die attach process and thin wafer technology the R_DS(on) of the devices is significantly reduced.
• Thermal resistance (R_thJC) is improved by up to 40 to 50%, as the conventional lead-based soft solder material has poorer thermal conductivity and acts as a thermal barrier for the heat generated on the junction of the MOSFET.
• Further benefits are a better manufacturability because there is no solder bleed-out and no chip tiltness as well as tighter R_DS(on) and R_thJC distribution, and finally an improved reliability and quality due to reduced electro-mechanical stress within the product.

The specifications of the new OptiMOS T2 40V, e.g. the IPB160N04S4-02D which provides 160A, offers a R_DS(on) of only 2.0 mΩ and a R_thJC of 0.9 K/W. The on-resistance is about 20% less compared to related devices using standard lead-based die attach soldering. In addition, the patented diffusion soldering technique results in a reduced ”chip-to-leadframe” thermal resistan.

Availability
The first OptiMOS T2 derivatives are available now: The IPB160N04S4-02D (with 160A in a TO-263 package), the IPB100N04S4-02D (100A, TO-263), the IPP100N04S4-03D (100A, TO-220) and the IPI100N04S4-03D (100A, TO-262).

Further information
Further information on Infineon’s automotive semiconductor portfolio and power products are available at www.infineon.com/automotivemosfet.

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