Smoltek has reported a major reliability milestone for its CNF-MIM capacitors, demonstrating more than 1,000 times lower current leakage in a new 1,000‑hour operational life test at 85 °C and 2 V, with no observed degradations across the tested batch.
The latest DCL leakage current results confirm the robustness of the carbon nanofiber-based CNF-MIM wafer based capacitor technology for demanding high-performance computing and AI data center applications.
Stronger Follow‑Up to Previous Reliability Test
The new long-term test follows an earlier 1,000‑hour reliability campaign completed in November 2025 on a previous CNF-MIM capacitor batch. In that earlier series, the capacitors showed minimal parameter drift over time but included a single early failure event. The latest 1,000‑hour operational life test on a subsequent batch now shows zero failures, with key electrical parameters remaining essentially unchanged from initial characterization.
According to Smoltek, the capacitors maintained their behavior throughout the full 1,000‑hour stress period at 85 °C and 2 V DC bias. The most striking improvement versus the previous campaign is the more than 1,000x reduction in leakage current, which translates into significantly higher insulation resistance at rated voltage.
Ultra‑Low Leakage and Insulation Resistance
The new CNF-MIM capacitors exhibit an insulation resistance on the order of 1,000 GΩ at 2 V DC, corresponding to a leakage current of only about 2 pA at rated voltage. This ultra‑low leakage is achieved while preserving high capacitance density and low ESR, and with no measurable drifts after the full 1,000‑hour life test.
By dramatically reducing leakage, Smoltek’s CNF-MIM technology minimizes continuous electrical stress and parasitic heat generation in operation. This directly supports improved long‑term stability of electronic systems, lowers the risk of field failures over product lifetime, and contributes to overall energy efficiency at the system level.
The combination of high capacitance density, very low ESR equivalent series resistance and extremely low leakage is particularly attractive for high‑performance computing and AI accelerator platforms. In these applications, dense decoupling close to advanced processors is critical to maintain power integrity under fast, high-current transients.
Lower leakage current not only reduces power losses but also helps to keep local temperatures down in densely packed modules and boards. For large AI data centers and HPC clusters, this can translate into more stable long‑term performance, fewer service interventions, and lower cooling and energy costs over time. Smoltek reports that these factors are increasingly important in discussions with potential industrial partners evaluating next‑generation capacitor technologies.
Key Electrical Performance Data
In the reported life test, the CNF-MIM capacitors were fully characterized before and after the 1,000‑hour operation, with no significant changes found in any of the primary figures of merit. The summarized electrical data are:
- Capacitance density: 170 nF/mm², unchanged after the 1,000‑hour life test.
- Equivalent Series Resistance (ESR): approximately 1,500 mΩ, unchanged after test completion.
- Insulation resistance: 1,000 GΩ at 2 V DC, corresponding to about 2 pA leakage current, again with no measurable degradation after the life test.
These results support Smoltek’s positioning of CNF-MIM as a high‑reliability capacitor technology suitable for advanced semiconductor packaging, 2.5D/3D integration and other space‑constrained applications that demand both high performance and long service life.
External Life Test in Progress
In parallel with the internal qualification work, Smoltek has initiated an external operational life test of CNF-MIM capacitors at an independent test house. The external campaign is expected to be completed by mid‑February 2026, with results anticipated to further validate the internal findings.
Smoltek expects that successful third‑party verification of the technology’s stability and leakage performance will strengthen ongoing dialogues with semiconductor and system-level partners. This external confirmation is an important step toward broader industrial adoption of CNF-MIM capacitors in future high‑density power distribution networks and advanced packaging platforms.
Source
This article is based on information provided by Smoltek in its official news and press release communication about CNF-MIM capacitors and their latest 1,000‑hour life test results.