22nm STT-MRAM for Reflow and Automotive Uses with High Yield, Reliability, and Magnetic Immunity and with Performance and Shielding Options

Gallagher, W. J.; Lee, George; Shih, Yu-Jen; Lee, Chia-Fu; Lee, Po-Hao; Wang, Ruo‐Qian; Shen, Kuei Hung; Wu, J. J.; Wang, Wayne; Chuang, Harry; Chien, Eric; Chiang, Tien-Wei; Shih, Meng-Chun; Wang, C.Y.; Weng, Chih-Hui; Chen, Sean; Bair, Christine

doi:10.1109/iedm19573.2019.8993469

Cited by 60 publications

(37 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fig. 2a shows the measured R-H hysteresis loops (averaged over ten cycles) of a defect-free device (upper) and a defective device (lower), with the same size eCD=55 nm; eCD stands for electrical Critical Diameter which is used to describe the MTJ size as a common practice in the MRAM community [2,19]. Due to the existence of H z s intra at the FL, the positive switching field H sw p and the negative switching field H sw n are asymmetric.…”

Section: A Magnetic Characterizationmentioning

confidence: 99%

“…INTRODUCTION As one of the most promising non-volatile memory technologies, spin-transfer torque magnetic random access memory (STT-MRAM) offers competitive write/read performance, endurance, density, retention, and power consumption [1]. The tunability of these aspects makes it customizable as both embedded and discrete memory solutions for a variety of applications such as Internet-of-Things (IoT), automotive, aerospace, and last-level caches [2]. Therefore, STT-MRAM technology has received a large amount of attention for commercialization from major semiconductor companies such as TSMC [2], Samsung [3], Intel [4], and SK hynix [5].…”

mentioning

confidence: 99%

“…The tunability of these aspects makes it customizable as both embedded and discrete memory solutions for a variety of applications such as Internet-of-Things (IoT), automotive, aerospace, and last-level caches [2]. Therefore, STT-MRAM technology has received a large amount of attention for commercialization from major semiconductor companies such as TSMC [2], Samsung [3], Intel [4], and SK hynix [5]. To enable STT-MRAM mass production, high-quality yet cost-efficient manufacturing test solutions are crucial to ensure the required quality of products being shipped to end customers.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Characterization, Modeling and Test of Synthetic Anti-Ferromagnet Flip Defect in STT-MRAMs

Rao

Taouil

et al. 2020

2020 IEEE International Test Conference (ITC)

View full text Add to dashboard Cite

Understanding the manufacturing defects in magnetic tunnel junctions (MTJs), which are the data-storing elements in STT-MRAMs, and their resultant faulty behaviors are crucial for developing high-quality test solutions. This paper introduces a new type of MTJ defect: synthetic anti-ferromagnet flip (SAFF) defect, wherein the magnetization in both the hard layer and reference layer of MTJ devices undergoes an unintended flip to the opposite direction. Both magnetic and electrical measurement data of SAFF defect in fabricated MTJ devices is presented; it shows that such a defect reverses the polarity of stray field at the free layer of MTJ, while it has no electrical impact on the single isolated device. The paper also demonstrates that using the conventional fault modeling and test approach fails to appropriately model and test such a defect. Therefore device-aware fault modeling and test approach is used. It first physically models the defect and incorporate it into a Verilog-A MTJ compact model, which is afterwards calibrated with silicon data. The model is thereafter used for fault analysis and modeling within an STT-MRAM array; simulation results show that a SAFF defect may lead to a transient passive neighborhood pattern sensitive fault (tPNPSF) when all neighboring cells are in logic '1' state. Finally, test solutions for such fault are discussed.Index Terms-Device-aware test, STT-MRAMs, manufacturing defects, fault models• Discover a new STT-MRAM-specific defect based on silicon measurements; the defect is referred to as SAFF. • Present magnetic and electrical characterization of MTJ devices with the SAFF defect.

show abstract

Section: A Magnetic Characterizationmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Characterization, Modeling and Test of Synthetic Anti-Ferromagnet Flip Defect in STT-MRAMs

Rao

Taouil

et al. 2020

2020 IEEE International Test Conference (ITC)

View full text Add to dashboard Cite

show abstract

“…Intel presented its embedded STT-MRAM solution in 2019 [30] and CMOS compatible process integration of SOT-MRAM in 2020 [31]. Samsung [14], Globalfoundries [4], and TSMC [32] demonstrated embedded STT-MRAM macros up to 1Gb in 2019. It is clear that Toggle-MRAM and STT-MRAM technologies are ready for mass production and deployment in the industry, while SOT-MRAM technology still requires further efforts in improving process and device/circuit co-optimization.…”

Section: Magnetic Random Access Memory (Mram)mentioning

confidence: 99%

Testing STT-MRAM: Manufacturing Defects, Fault Models, and Test Solutions

Rao

Taouil

et al. 2021

2021 IEEE International Test Conference (ITC)

View full text Add to dashboard Cite

“…A viable way of reducing the power consumption is the introduction of non-volatility in integrated circuits. Spintransfer torque magnetoresistive random access memory (STT-MRAM) combines high speed, excellent endurance, low costs, and is thus promising for applications ranging from IoT and automotive applications [1]- [5] to embedded DRAM, and last level caches [6], [7].…”

Section: Introductionmentioning

confidence: 99%

Analysis of Switching Under Fixed Voltage and Fixed Current in Perpendicular STT-MRAM

Fiorentini

Orio

Selberherr

et al. 2020

IEEE J. Electron Devices Soc.

View full text Add to dashboard Cite

In spin-transfer torque magnetoresistive random access memory, the magnetization dynamics of a free layer is usually assumed to be determined by the torque created via a position-independent current density. In circuits, however, it is the voltage, not the current density, which stays fixed during switching. Therefore, the approximate evaluation of the torque based on a fixed current density becomes questionable in modern magnetic tunnel junctions with a tunneling magnetoresistance ratio of about 200%, where the current density across the structure can vary by a factor of three. In this work, we compare the switching times obtained within a fixed voltage assumption with those from the approximate fixed current density assumption. We demonstrate that the assumption of a fixed current can reproduce the correct switching if the current is appropriately adjusted. It is shown that the correction to the current is not universal and depends on various factors such as TMR, temperature, the size of the structure and resistance area.

show abstract

22nm STT-MRAM for Reflow and Automotive Uses with High Yield, Reliability, and Magnetic Immunity and with Performance and Shielding Options

Cited by 60 publications

References 2 publications

Characterization, Modeling and Test of Synthetic Anti-Ferromagnet Flip Defect in STT-MRAMs

Characterization, Modeling and Test of Synthetic Anti-Ferromagnet Flip Defect in STT-MRAMs

Testing STT-MRAM: Manufacturing Defects, Fault Models, and Test Solutions

Analysis of Switching Under Fixed Voltage and Fixed Current in Perpendicular STT-MRAM

Contact Info

Product

Resources

About