Built-in Self-Test and Fault Localization for Inter-Layer Vias in Monolithic 3D ICs

Monolithic 3D (M3D) integration provides massive vertical integration through the use of nanoscale inter-layer vias (ILVs). However, high integration density and aggressive scaling of the inter-layer dielectric make ILVs especially prone to defects. We present a low-cost built-in self-test (BIST) method that requires only two test patterns to detect opens, stuck-at faults, and bridging faults (shorts) in ILVs. We also propose an extended BIST architecture for fault detection, called Dual-BIST, to guarantee zero ILV fault masking due to single BIST faults and negligible ILV fault masking due to multiple BIST faults. We analyze the impact of coupling between adjacent ILVs arranged in a 1D array in block-level partitioned designs. Based on this analysis, we present a novel test architecture called Shared-BIST with the added functionality of localizing single and multiple faults, including coupling-induced faults. We introduce a systematic clustering-based method for designing and integrating a delay bank with the Shared-BIST architecture for testing small-delay defects in ILVs with minimal yield loss. Simulation results for four two-tier M3D benchmark designs highlight the effectiveness of the proposed BIST framework.

Design of a Fully Integrated VHF CP-PLL Frequency Synthesizer with an All-Digital Defect-Oriented Built-In Self-Test.

This paper presents the design of an on-chip charge pump phase-locked loop (CP-PLL) with a fully digital defect oriented built-in self-test (BIST) for very-high frequency (VHF) applications. The frequency synthesizer has a 40 to 100 MHz tuning range and uses a ring voltage-controlled oscillator for frequency synthesis. The PLL exhibits a phase noise of -132 dBc/Hz at 1 MHz and consumes 1.8 mW on a 3 V supply. The BIST implementation uses fewer external input or output, is capable of efficient fault diagnosis, and is compact, posing a low area overhead. The integrated circuit design was realized in the AMI 0.6µ complementary metal oxide-semiconductor process.

Assessing the efficacy of an integrated intervention to create demand for fishermen’s schistosomiasis and HIV services (FISH) in Mangochi, Malawi: Study protocol for a cluster randomized control trial

Background Both HIV and schistosomiasis are major public health problems worldwide with 1.8 million new HIV infections, and up to 110 million untreated schistosomiasis cases globally. Although a causal link has not been established, there are strong suggestions that having schistosomiasis increases onward transmission of HIV from co-infected men to women. With both HIV and schistosomiasis treatment readily available in Malawi, there is a need to investigate the feasibility, acceptability and health impacts of joint management of these two hazards, with special focus on health education and demand-creation for fishermen. The aim of this project is to identify optimal models of delivering integrated HIV and schistosomiasis services for fishermen, particularly investigating the effect of using social networks, HIV self-test kits and beach clinic services in Mangochi, Malawi. Methods We have mapped 45 boat teams or landing sites for a 3-arm cluster randomized trial using “boat team” as the unit of randomization. The three arms are: 1) Standard of care (SOC) with leaflets explaining the importance of receiving presumptive treatment for schistosomiasis (praziquantel) and HIV services for fishermen, and two intervention arms of 2) SOC + a peer explaining the leaflet to his fellow fishermen in a boat team; and 3) arm 2 with HIV self-test kits delivered to the boat team fishermen by the peer. The primary outcomes measured at 9 months of trial delivery will compare differences between arms in the proportions of boat-team fishermen: 1) who self-report starting antiretroviral therapy or undergoing voluntary medical male circumcision; and 2) who have ≥1 S. haematobium egg seen on light microscopy of the filtrate from 10mls urine (“egg-positive”). Discussion This is the first evaluation of an integrated HIV and schistosomiasis services intervention for fishermen, particularly investigating the effect of using social networks, HIVST kits and beach clinic services. The findings will support future efforts to integrate HIVST with other health services for fishermen in similar settings if found to be efficacious. Trial registration This trial is registered in the ISRCTN registry: ISRCTN14354324; date of registration: 05 October 2020. https://www.isrctn.com/ISRCTN14354324?q=ISRCTN14354324&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search. Linked to protocol version number 1.4 of 11 January 2021.

Operationalizing the distribution of oral HIV self-testing kits to men who have sex with men (MSM) in a highly homophobic environment: the Nigerian experience

Background Self-care health interventions are innovative approaches for improving health and achieving the sustainable development goals (SDGs). Men who have sex with men (MSM) have been disproportionately affected by Human Immunodeficiency Virus (HIV). In spite of this, stigma from healthcare workers has reportedly prevented MSM from accessing HIV testing in health facilities. This paper explored the operationalization of using key opinion leaders (KOLs) to distribute HIVST (HIV self-test) kits to MSM. This qualitative survey used a combination of in-depth interviews (IDI) with HIVST users and focus group discussions (FGDs) with KOLs to collect data three months after the distribution of the test kits by the KOLs. Thematic analysis of the data was carried out. Result Three themes were generated namely: KOLs serve as a trusted resource to promote and support HIVST for the MSM community; Skills and qualifications required for KOLs to effectively distribute and promote uptake of HIVST; and Effective strategies used to create demand and promote uptake of HIVST. Conclusion This study showed the practical steps involved in operationalizing KOL support system distribution of HIVST that positively influenced the testing experience for the participants irrespective of the HIV status and engagement in care. KOLs are a reliable resource to leverage for ensuring that HIV self-test kit is utilized and HIV positive individuals are linked to treatment and care in homophobic environments.

Stress-Aware Periodic Test of Interconnects

Safety-critical systems have to follow extremely high dependability requirements as specified in the standards for automotive, air, and space applications. The required high fault coverage at runtime is usually obtained by a combination of concurrent error detection or correction and periodic tests within rather short time intervals. The concurrent scheme ensures the integrity of computed results while the periodic test has to identify potential aging problems and to prevent any fault accumulation which may invalidate the concurrent error detection mechanism. Such periodic built-in self-test (BIST) schemes are already commercialized for memories and for random logic. The paper at hand extends this approach to interconnect structures. A BIST scheme is presented which targets interconnect defects before they will actually affect the system functionality at nominal speed. A BIST schedule is developed which significantly reduces aging caused by electromigration during the lifetime application of the periodic test.

Constant-sized correlations are sufficient to self-test maximally entangled states with unbounded dimension

Let p be an odd prime and let r be the smallest generator of the multiplicative group Zp∗. We show that there exists a correlation of size Θ(r2) that self-tests a maximally entangled state of local dimension p−1. The construction of the correlation uses the embedding procedure proposed by Slofstra (Forum of Mathematics, Pi. (2019)). Since there are infinitely many prime numbers whose smallest multiplicative generator is in the set {2,3,5} (D.R. Heath-Brown The Quarterly Journal of Mathematics (1986) and M. Murty The Mathematical Intelligencer (1988)), our result implies that constant-sized correlations are sufficient for self-testing of maximally entangled states with unbounded local dimension.

Remote Delivery of the Chronic Pain Self-management Program Using Self-directed Materials and Small-group Telephone Support: A Pilot Study

A remote (telephone and tool kit) chronic pain program was studied using the RE-AIM (reach, effectiveness, adoption, implementation, and maintenance) framework. This 6-week pilot took place in underserved communities in Cleveland, Ohio. We determined reach by the diversity of the population, nearly 50% Black and mostly low income. Effectiveness over 7 weeks was shown with validated instruments (depression, pain, sleep, quality of life, self-rated health, and self-efficacy). Changes in pain, depression, and self-efficacy were significant. ( p < .01). Remote implementation was accomplished by sending participants a box of materials (book, exercise and relaxation CDs, a self-test, and tip sheets). Participants also participated in peer-facilitated, weekly, scripted telephone calls. Maintenance was demonstrated as the study site has offered nine additional programs with more plan. In addition, 60 additional organizations are now offering the program. This proof-of-concept study offers an alternate to in-person chronic pain self-management program delivery.

A dual mode self-test for a stand alone AES core

Advanced Encryption Standard (AES) is the most secured ciphertext algorithm that is unbreakable in a software platform’s reasonable time. AES has been proved to be the most robust symmetric encryption algorithm declared by the USA Government. Its hardware implementation offers much higher speed and physical security than that of its software implementation. The testability and hardware Trojans are two significant concerns that make the AES chip complex and vulnerable. The problem of testability in the complex AES chip is not addressed yet, and also, the hardware Trojan insertion into the chip may be a significant security threat by leaking information to the intruder. The proposed method is a dual-mode self-test architecture that can detect the hardware Trojans at the manufacturing test and perform an online parametric test to identify parametric chip defects. This work contributes to partitioning the AES circuit into small blocks and comparing adjacent blocks to ensure self-referencing. The detection accuracy is sharpened by a comparative power ratio threshold, determined by process variations and the accuracy of the built-in current sensors. This architecture can reduce the delay, power consumption, and area overhead compared to other works.