Ring-Oscillator (RO) are most suitable to investigate the reliability of digital CMOS circuits operating up to GHz frequencies as a good correlation has been observed between RO degradation and Product Fmax degradation. In addition, the RO degradation testing can be performed with similar equipment used for discrete device reliability characterization. In this work, we discuss the role of BTI/HCI contribution in RO degradation and compare the contributions of NFET and PFET devices. To decouple BTI/HCI contribution, AC characterization on discrete devices is conducted and correlated to the RO degradation under diverse testing conditions. Additionally, specially designed reliability RO are used to quantify device type contribution under RO stress.

中文翻译：

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用于高级 CMOS 技术的环形振荡器电路的可靠性表征

环形振荡器 (RO) 最适合研究在高达 GHz 频率下工作的数字 CMOS 电路的可靠性，因为已经观察到 RO 退化和产品 Fmax 退化之间存在良好的相关性。此外，可以使用用于分立器件可靠性表征的类似设备执行 RO 退化测试。在这项工作中，我们讨论了 BTI/HCI 对 RO 退化的贡献，并比较了 NFET 和 PFET 器件的贡献。为了解耦 BTI/HCI 的影响，在不同的测试条件下对分立器件进行 AC 表征并与 RO 退化相关联。此外，专门设计的可靠性 RO 用于量化 RO 应力下的器件类型贡献。