Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Caractérisation morphologique et électrique du collage hybride jusqu'aux pas submicroniques

L’intégration 3D, qui consiste à empiler les puces de différentes technologies et fonctionnalités les unes sur les autres, a émergé au cours des dernières années comme une alternative de la loi de Moore pour poursuivre l’élaboration de puces multifonctions et l’amélioration des performances des circuits intégrés. Le collage hybride, une des différentes techniques de l’intégration 3D, peut répondre aux besoins de miniaturisation avec la possibilité de réduire le pas d’interconnexion au-dessous d’un micromètre, ce qui permettra la conception des dispositifs plus performants notamment pour les capteurs d’image. Les effets d’une telle miniaturisation sur les propriétés thermomécaniques et électriques ainsi que sur la robustesse des interconnexions en collage hybride sont, cependant, inconnues.L’objectif de cette thèse est d’étudier, dans une intégration par collage hybride, les défis de la réduction du pas d'interconnexion jusqu'en dessous du micromètre. La méthodologie a consisté d’étudier, avec la réduction du pas, le mécanisme de fermeture de l’interface de collage, la fiabilité des interconnexions au niveau collage hybride ainsi que leurs performances électriques. En utilisant la technique de Microdiffraction de Laue à l’ESRF, une orientation cristalline favorisant la fermeture de l’interface à l’échelle submicronique a été mise en évidence. La résistivité de contact extraite par une nouvelle méthode d’estimation a permis de définir les spécifications de fabrication pour obtenir une reconstruction parfaite de l'interface Cu-Cu avec une résistivité de contact proche de celle de joint des grains de Cu. Malgré la modification du mode de défaillance en électromigration avec une cavité tueuse au niveau des plots de collage pour les pas inférieurs à 3.5 µm, les performances électriques à des conditions normales d'utilisation ne sont pas affectées. A l’aide d’une nouvelle méthodologie de test, nous avons montré que le mode de dégradation en claquage de diélectrique (TDDB) au niveau de collage hybride est atypique par rapport au BEoL standard. Des analyses fines ont permis de lier ce comportement à une couche de Cu2O, présente à l’interface Cu/SiO2, qui agit comme une barrière et qui rend l’intégration Cu/SiO2 immune à la diffusion de cuivre. Cette compréhension fine du mécanisme de collage et de la robustesse de l’interface a permis de démontrer que le collage hybride est possible au moins jusqu’au pas de 0.67 µm et de proposer de nouvelles architectures pour améliorer la performance électrique.The 3D integration technology has emerged in the last decade as a key process to combine multi-functional and technological integrated circuit devices to produce a single chip with small form factor and enhanced electrical performances. The hybrid bonding technology, one of the different 3D stacking options, is adapted for advanced device miniaturization with the possibility of reducing the hybrid bonding pitch below one micrometer. This would allow the design of more efficient devices, especially for image sensors. However, the impact of such aggressive interconnection pitch scaling on the bonding mechanism, the electrical performance and the reliability of the hybrid bonding level remains to be studied.The goal of this PhD thesis is to study, for the Cu/SiO2 hybrid bonding integration, the challenges of reducing the hybrid bonding pitch down to sub-micron. To target this, we studied a possible change in the Cu interface closure mechanism with the reduction of the Cu pad width. Using the Laue-microdiffraction technique at the ESRF, a specific crystalline orientation favorizing the closure of Cu-Cu interface at the sub-micron pitch level was put in evidence. From an electrical point of view, new methods were developed to precisely extract the Cu-Cu interface resistivity allowing the define the fabrication specifications to obtain an interface reconstruction close to Cu grain boundary one. Despite the modification of the electromigration degradation mode with a killer defect at the hybrid bonding level for Cu pads below 3.5 µm in width, the electrical performances at use conditions are not affected. Moreover, using a new test methodology, we have put in evidence for the first time at the hybrid bonding level a modified degradation mode under Time Dependent Dielectric Breakdown (TDDB) as compared to standard BEoL behaviour. Deep analyses on the atomic and ionic diffusion mechanisms allowed to link this modified behaviour to the presence of a thin Cu2O layer at the Cu/SiO2 interface, which behaves as a barrier against Cu diffusion in SiO2. This profound understanding of the bonding mechanism and interface robustness and reliability allowed us to demonstrate that hybrid bonding is possible at least down to 0.67 µm and to propose new architectures allowing enhanced electrical performances with pitch reduction

Electrical and morphological characterizations of the hybrid bonding level down to submicron pitches

L’intégration 3D, qui consiste à empiler les puces de différentes technologies et fonctionnalités les unes sur les autres, a émergé au cours des dernières années comme une alternative de la loi de Moore pour poursuivre l’élaboration de puces multifonctions et l’amélioration des performances des circuits intégrés. Le collage hybride, une des différentes techniques de l’intégration 3D, peut répondre aux besoins de miniaturisation avec la possibilité de réduire le pas d’interconnexion au-dessous d’un micromètre, ce qui permettra la conception des dispositifs plus performants notamment pour les capteurs d’image. Les effets d’une telle miniaturisation sur les propriétés thermomécaniques et électriques ainsi que sur la robustesse des interconnexions en collage hybride sont, cependant, inconnues.L’objectif de cette thèse est d’étudier, dans une intégration par collage hybride, les défis de la réduction du pas d'interconnexion jusqu'en dessous du micromètre. La méthodologie a consisté d’étudier, avec la réduction du pas, le mécanisme de fermeture de l’interface de collage, la fiabilité des interconnexions au niveau collage hybride ainsi que leurs performances électriques. En utilisant la technique de Microdiffraction de Laue à l’ESRF, une orientation cristalline favorisant la fermeture de l’interface à l’échelle submicronique a été mise en évidence. La résistivité de contact extraite par une nouvelle méthode d’estimation a permis de définir les spécifications de fabrication pour obtenir une reconstruction parfaite de l'interface Cu-Cu avec une résistivité de contact proche de celle de joint des grains de Cu. Malgré la modification du mode de défaillance en électromigration avec une cavité tueuse au niveau des plots de collage pour les pas inférieurs à 3.5 µm, les performances électriques à des conditions normales d'utilisation ne sont pas affectées. A l’aide d’une nouvelle méthodologie de test, nous avons montré que le mode de dégradation en claquage de diélectrique (TDDB) au niveau de collage hybride est atypique par rapport au BEoL standard. Des analyses fines ont permis de lier ce comportement à une couche de Cu2O, présente à l’interface Cu/SiO2, qui agit comme une barrière et qui rend l’intégration Cu/SiO2 immune à la diffusion de cuivre. Cette compréhension fine du mécanisme de collage et de la robustesse de l’interface a permis de démontrer que le collage hybride est possible au moins jusqu’au pas de 0.67 µm et de proposer de nouvelles architectures pour améliorer la performance électrique.The 3D integration technology has emerged in the last decade as a key process to combine multi-functional and technological integrated circuit devices to produce a single chip with small form factor and enhanced electrical performances. The hybrid bonding technology, one of the different 3D stacking options, is adapted for advanced device miniaturization with the possibility of reducing the hybrid bonding pitch below one micrometer. This would allow the design of more efficient devices, especially for image sensors. However, the impact of such aggressive interconnection pitch scaling on the bonding mechanism, the electrical performance and the reliability of the hybrid bonding level remains to be studied.The goal of this PhD thesis is to study, for the Cu/SiO2 hybrid bonding integration, the challenges of reducing the hybrid bonding pitch down to sub-micron. To target this, we studied a possible change in the Cu interface closure mechanism with the reduction of the Cu pad width. Using the Laue-microdiffraction technique at the ESRF, a specific crystalline orientation favorizing the closure of Cu-Cu interface at the sub-micron pitch level was put in evidence. From an electrical point of view, new methods were developed to precisely extract the Cu-Cu interface resistivity allowing the define the fabrication specifications to obtain an interface reconstruction close to Cu grain boundary one. Despite the modification of the electromigration degradation mode with a killer defect at the hybrid bonding level for Cu pads below 3.5 µm in width, the electrical performances at use conditions are not affected. Moreover, using a new test methodology, we have put in evidence for the first time at the hybrid bonding level a modified degradation mode under Time Dependent Dielectric Breakdown (TDDB) as compared to standard BEoL behaviour. Deep analyses on the atomic and ionic diffusion mechanisms allowed to link this modified behaviour to the presence of a thin Cu2O layer at the Cu/SiO2 interface, which behaves as a barrier against Cu diffusion in SiO2. This profound understanding of the bonding mechanism and interface robustness and reliability allowed us to demonstrate that hybrid bonding is possible at least down to 0.67 µm and to propose new architectures allowing enhanced electrical performances with pitch reduction

Recent Advances on Qualification and Reliability of Cu/SiO2 to Cu/SiO2 Hybrid Bonds for 3D ICs

International audienc

Investigation into Cu diffusion at the Cu/SiO2 hybrid bonding interface of 3D stacked integrated circuits

Reliability concerns are often risen for the hybrid bonding integration due to a potential misalignment in the bonding step leading that Cu directly faces dielectric at the hybrid bonding interface. Any Cu atomic or ionic diffusion could lead to serious decrease of the product lifetime. In the case of Cu/SiO2 interface, a self-formed cuprous oxide (Cu2O) layer that has some diffusion barrier characteristics was previously evidenced in the critical region where Cu is facing SiO2. In this paper, we investigate the immunity to both thermal (atomic) and field-enhanced Cu ion diffusion of the self-formed Cu2O barrier for the Cu/SiO2 hybrid bonding integration. The study of thermal diffusion by high precision analysis techniques shows limited Cu traces after bonding annealing. The same levels of Cu were also found in the presence of a SiN barrier. This study proves that the self-formed cuprous oxide and SiN have similar characteristics in decelerating Cu atomic diffusion. In addition, the study of the field-enhanced diffusion confirms that Cu2O is an effective barrier to Cu ionic drift even after long-term storage, which is chemically validated by a thermally stable interface. This self-formed Cu2O layer provides a negligible impact of Cu diffusion on the device performance

(Invited) Hybrid Bonding-Based Interconnects: A Status on the Last Robustness and Reliability Achievements

International audienc

Review—Hybrid Bonding-Based Interconnects: A Status on the Last Robustness and Reliability Achievements

International audienceAbstract This paper reviews the most significant qualification and reliability achievements obtained, over the last 6 years, by the scientific community for hybrid bonding-based interconnects (HB) also called Cu-Cu or Cu/SiO2 bonding. First, the definition of words qualification, robustness and reliability are given to avoid misunderstanding about the published results. Second, the five potential threats (moisture ingress, thermomechanical stresses,electromigration, Cu diffusion, dielectric breakdown) are presented. Finally, the publications of six industrials or research and technology organizations are summarized and discussed. Most of the published data are related to qualification results (pass or fail). Few studies published in-depth studies, mainly on electromigration (Black’s parameters extraction and failure analysis) and copper diffusion (electrical and analytical characterizations). To conclude, once the manufacturing issues (surface preparation, alignment…) have been solved, this technology is robust and reliable at pitches > 1 μm as it reacts, roughly, like a conventional back-end of line (BEoL) interconnect

New Method to Perform TDDB Tests for Hybrid Bonding Interconnects

Hybrid Bonding (HB) is progressing as the major solution for 3D integrated-circuit with pitch reduction becoming the key. Reliability needs to be studied with HB pitch reduction for possible evaluation of new failure mechanisms and modes. In this paper, we developed a new methodology to study Time-Dependent Dielectric Breakdown (TDDB) at HB level that accounts wafer-to-wafer (W2W) overlay variations. Application of this method to a 1.44 µm-pitch 3D stacked test vehicle demonstrates its accuracy. TDDB at Cu/SiO2 HB interface follows the 1/E model at low electric fields for all studied temperature suggesting that the role of Cu in breakdown is negligible. The acceleration parameter and the activation energy dependence on the electric fields are studied. The cuprous oxide layer which may act as a barrier to Cu diffusion previously highlighted at the Cu/SiO2 HB interface does not exist for Cu/SiN interfaces as evidenced by EELS study. This might explain the difference in the TDDB acceleration models between HB level and BEoL ones

Thermomechanical Characterizations of Copper at Nanoscale by Laue Microdiffraction

The investigation of copper microstructure at nanoscale using synchrotron-based Laue microdiffraction technique is presented. Based on the experimental findings, FEM simulations allow to extract the plastic behaviour dependence on the orientation for the single crystals. The results obtained are used to achieve Cu/SiO2 hybrid bonding with 300 nm Cu pads.NANOELE