NTC Thermistors for Embedded Power Semiconductor Modules

CORE.POWER.PACKAGING

This brief is based on the supplied packaging requirements. Temperature, pressure, thickness, and packaging ranges should be validated against the target process flow before they are used as component specifications.

01. Planarity and Thickness Become System Requirements

Embedding a thermistor beside a SiC or GaN die makes it part of a multilayer composite, not a standalone mounted component. The supplied framing notes that die thickness can be far below conventional SMT component thickness, so mismatch can create resin voids, uneven lamination, or local stress concentrations.

Flat, parallel surfaces and a smaller footprint are therefore central requirements. The target geometry must support placement near the power die for thermal coupling without disrupting substrate routing or mechanical lamination.

02. Thermal and Mechanical Survivability Move Beyond Standard Reflow

Conventional SMT thermistors are typically designed around solder reflow and lower operating-temperature assumptions. The supplied requirement set anticipates sintering processes around 250°C to 300°C, mechanical pressure in the single- to double-digit MPa range, and SiC-module operation approaching 175°C to 200°C.

These are not incremental qualification changes. They alter the required material stack, mechanical robustness, and process-screening conditions for a thermistor intended to survive embedded power-module assembly.

03. Electrode Chemistry Is the Critical Interface

The supplied assessment identifies metallization as the largest departure from standard SMT design. A tin-based termination that is acceptable in conventional assembly may be incompatible with high-temperature lamination, sintering, and surrounding PCB chemistry.

The design question is therefore not only how small the NTC can become. It is whether the electrode stack can remain stable, electrically reliable, and process-compatible through the complete embedded-package flow.