Summary of Tutorials

Tutorial 1: Memory Technology: Reliability Challenges and Future PerspectivesAbstract: Memory technologies occupy a huge share of the semiconductor market. Despite a large plethora of memory device concepts proposed over the years, only a restricted group of them has achieved large-scale production. Reliability is one of the main aspects limiting the adoption of a memory technology by the semiconductor industry. This tutorial aims at outlining the main reliability characteristics of memory devices and the characterization techniques to assess them. Representative case studies, namely RRAM and DRAM, are provided, to review the challenges to be overcome before a memory technology is widely accepted by the industry, and to describe how the causes of reliability failure are identified and mitigated. As the pursuit of innovative memory devices and architectures is relentless and fast-paced, this tutorial also provides future perspectives on memory technology and the related reliability challenges.Tutorial 2: Reliability of Energy-Efficient Phase Change Memory Based on Novel Superlattices and NanocompositesAbstract: Today’s computing systems are reaching fundamental limits with conventional materials like silicon, and with conventional layouts that separate memory and computing. To overcome these challenges, phase change memory (PCM) technology based on chalcogenides like Ge2Sb2Te5 (GST225) hold great promise for both data storage and neuromorphic computing. However, using conventional phase change materials, PCM operation requires large power consumption and suffers from resistance drift, limiting its potential for neuro-inspired and energy-efficient data storage. In this tutorial, we will address some of these challenges in PCM devices using novel phase change nanocomposite Ge4Sb6Te7 (GST467) and GST based phase-change superlattices. We will discuss the operation of energy-efficient and neuro-inspired PCM devices demonstrating gradual change of resistance states, low power switching, and multilevel operation with low resistance drift. We will also focus on the fundamental correlation between superlattice material characteristics and PCM device performance, important to ensure reliability and robustness of such technology for low power and brain-inspired computing.Tutorial 3: Brief Introduction to Device and Circuit ReliabilityAbstract: After a brief review of selected reliability basics, we discuss the main degradation mechanisms occurring in Field-Effect Transistors (FETs). These mechanisms include SILC (Stress Induced Leakage Current), TDDB (Time-Dependent Dielectric Breakdown), BTI (Bias Temperature Instability), RTN (Random Telegraph Noise), and HCD (Hot Carrier Degradation) with the accompanying Self-Heating (SHE) and are linked with the underlying properties of defects. The effects of Mechanical Stress are also briefly reviewed. We then show that these defects play the essential role in many emerging technologies and applications, including CryoCMOS and 2D FETs, and are responsible for degradation variability in deeply-scaled devices. Finally, we show how device degradation can be accounted for in circuit simulations and demonstrate how in-depth knowledge of defect properties can be used to our advantage to design new devices and applications.Tutorial 4: 22FDX® RF/mmWave ReliabilityAbstract. The Fully Depleted Silicon on Insulator (FDSOI) technology was proven to be one of the best candidate for radio frequency (RF) and millimeter wave (mmWave) applications with lowest power consumption, lowest system footprint and the efficient electrostatic control of short channel effects. These advantages in addition with back-bias tuning and scalability knob offered by FDSOI technology give designers more freedom to explore and enhance their RF/mmWave designs. They need to push the devices at their limits to optimize and unlock best competitiveness for their IPs/designs. It results in high voltage/current stress to the devices, challenging standard technology qualification reliability models and their coverage. This tutorial will offer an overview about 22FDX® reliability effort to support the RF/mmWave design. It will include Non Conducting hot carrier injection (NCHCI) studies, off-state TDDB modeling, HCI Low Vgs modeling, Safe Operating Area methodology based on TDDB & RF/mmWave waveform analysis. The waveform analysis provides a base for assessing RF operation based on all DC reliability models and helps sizing critical RF/mmWave IPs for safe product lifetime, reducing design iterations to final product.