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The purpose of this paper is to investigate the effect of high-k material HfO₂ as a buffer layer for the fabrication of metal-ferroelectric-insulator-silicon (MFeIS) structures on Si (100) substrate.

RF-sputtered Pb[Zr0.35Ti0.65]O₃ or (PZT) and plasma-enhanced atomic layer deposited HfO₂ films were selected as the ferroelectric and high-k buffer layer, respectively, for the fabrication of metal-ferroelectric-insulator-silicon (MFeIS) structures on Si (100) substrate. Multiple angle ellipsometry and X-ray diffraction analysis was carried out to obtain the crystal orientation, refractive index and absorption coefficient parameters of the deposited/annealed films. In the different range of annealing temperature, the refractive index was observed in the range of 2.9 to 2 and 1.86 to 2.64 for the PZT and HfO₂ films, respectively

Electrical and ferroelectric properties of the dielectric and ferroelectric films and their stacks were obtained by fabricating the metal/ferroelectric/silicon (MFeS), metal/ferroelectric/metal, metal/insulator/silicon and MFeIS capacitor structures. A closed hysteresis loop with remnant polarization of 4.6 µC/cm² and coercive voltage of 2.1 V was observed in the PZT film annealed at 5000 C. Introduction of HfO₂ buffer layer (10 nm) improves the memory window from 5.12 V in MFeS to 6.4 V in MFeIS structure with one order reduction in the leakage current density. The same MFeS device was found having excellent fatigue resistance property for greater than 1010 read/write cycles and data retention time more than 3 h.

The MFeIS structure has been fabricated with constant PZT thickness and varied buffer layer (HfO₂) thickness. Electrical characteristics shows the improved leakage current and memory window in the MFeIS structures as compared to the MFeS structures. Optimized MFeIS structure with 10-nm buffer layer shows the excellent ferroelectric properties with endurance greater than E10 read/write cycles and data retention time higher than 3 h. The above properties indicate the MFe(100 nm)I(10 nm)S gate stack as a potential candidate for the FeFET-based nonvolatile memory applications.

A tailored graphical user interface (GUI) for finite element analysis, fully integrated into Microsoft Windows 3.1, has been developed. The current application is the simulation of flat sheet extrusion of thermoplastics, but many of the features would be common to a wide range of finite element analyses. Microsoft’s C/C++ Professional Development System 7.0, including the Software Development Kit 3.1 (SDK), has been used as the programming tool for the GUI. The interface is based on the Common User Access Advanced Interface Design Guide, which is part of the IBM Systems Application Architecture Library, and The Windows Interface: An Application Design Guide, which is part of the SDK. A memory handling technique is proposed to break the imposed 64 KB data segmentation. Connected finite element calculation routines are written in Fortran and compiled by the Salford FTN77/x86 32‐bit compiler. The protected mode interface of the Fortran compiler allows direct access by the GUI, and allows the computation to run as a 32‐bit background application, without memory limitations, in the multitasking environment. Finite element routines are supported by pre‐ and post‐processors comprising mesh generation, post‐processing for derived results, and graphical displays. A convenient contouring algorithm is proposed to generate contoured plots of nodal quantities in the form of iso‐lines or iso‐fields.

How can you call yourself a serious computer user if you don't have a 33MHz 486 system with a 16″ 1024×768 Super VGA screen and 300MB disk drive? Run right out and get the new goodies—otherwise, you're wasting your precious time. The above is an extreme position. On the other hand, if you're still using the equivalent of an IBM PC/XT (or, worse yet, an original PC), you're at the other extreme. Quite apart from the hype, you would almost certainly benefit from a more powerful PC. For most of us in the real world who are spending real dollars for equipment to serve real needs, the decisions can be tough: upgrade, replace, or let it be? And, if upgrading is the answer, what should you upgrade? This column deals with hardware questions. While there are few firm rules, there are some reasonable guidelines to consider. The author also provides notes from January‐June 1991 PC literature; it's been a great period for powermongers!

In the DOS world, Windows 3.0 is an operating environment that utilizes a Graphical User Interface, or “GUI.” A GUI is an alternative to typing as a means of interacting with the computer and its operating system that is intended to be superior, in some ways, to the operating system itself. It is not a replacement for the operating system (e.g., DOS 3.31 or DOS 5.0). The principal features and strengths of Windows 3.0 are examined, as is a suite of programs—Word for Windows, Excel for Windows, and PowerPoint for Windows—which are collectively packaged as Microsoft Office for Windows. While not “perfect,” there is a significant advantage to the uniformity of the Windows environment.

Development of (1T-type) ferroelectric random access memory (FeRAM) has most actively progressed since 1995 and motivated by the physical limits and technological drawbacks of the flash memory. 1T-type FeRAM implements ferroelectric layer at the field effect transistor (FET) gate. During the course of the investigation, it was very difficult to form a thermodynamically stable ferroelectric-semiconductor interface at the FET gate, leading to the introduction of one insulating buffer layer between the ferroelectric and the silicon substrate to overcome this problem. In this study, Al₂O₃ a high-k buffer layer deposited by plasma enhanced atomic layer deposition (PEALD) is sandwiched between the ferroelectric layer and silicon substrate.

Ferroelectric/high-k gate stack were fabricated on the silicon substrate and pt electrode. Structural characteristics of the ferroelectric (PZT) and high-k (Al₂O₃) thin film deposited by RF sputtering and PEALD, respectively, were optimized and investigated for different process parameters. Metal/PZT/Metal, Metal/PZT/Silicon, Metal/PZT/Al₂O₃/Silicon structures were fabricated and electrically characterized to obtain the memory window, leakage current, hysteresis, PUND, endurance and breakdown characteristics.

XRD pattern shows the ferroelectric perovskite thin Pb[Zr_0.35Ti_0.65]O₃ film with (101) tetragonal orientation deposited by sputtering and PEALD Al₂O₃ with (312) orientation showing amorphous nature. Multiple angle analysis shows that the refractive index of PZT varies from 2.248 to 2.569, and PEALD Al₂O₃ varies from 1.6560 to 1.6957 with post-deposition annealing temperature. Increase in memory window from 2.3 to 8.4 V for the Metal-Ferroelectric-Silicon (MFS) and Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure has been observed at the annealing temperature of 500°C. MFIS structure with 10 nm buffer layer shows excellent endurance of 3 × 109 read-write cycles and the breakdown voltage of 33 V.

This paper shows the feature, principle and improvement in the electrical properties of the fabricated gate stack for 1T-type nonvolatile FeFET. The insulating buffer layer sandwiched between ferroelectric and silicon substrate acts as a barrier to ferroelectric–silicon interdiffusion improves the leakage current, memory window, endurance and breakdown voltage. This is perhaps the first time that the combination of sputtered PZT on the PEALD Al₂O₃ layer is being reported.

The purpose of this paper is to report on a sequential three-stage analysis of inflation persistence using monthly data from 11 inflation targeting (IT) countries and, for comparison, the USA, a non-IT country with a history of credible monetary policy.

First, the authors estimate inflation persistence in a rolling-window fractional-integration setting using the semiparametric estimator suggested by Phillips (2007). Second, the authors use tests for unknown structural breaks as a means to identify effects of the regime switch and the global financial crisis on inflation persistence. The authors use the sequences of estimated persistence measures from the first stage as dependent variables in the Bai and Perron (2003) structural break tests. Finally, the authors reapply the Phillips (2007) estimator to the subsamples defined by the breaks.

Four countries (Canada, Iceland, Mexico, and South Korea) experience a structural break in inflation persistence that coincide with the implementation of the IT regime, and three IT countries (Sweden, Switzerland, and the UK), as well as the USA experience a structural break in inflation persistence that coincides with the global financial crisis.

The authors find that in most cases the estimates of inflation persistence switch from mean-reversion nonstationarity to mean-reversion stationarity.

Monetary policy implications differ between pre- and post-global financial crisis.

Global financial crisis affected the persistence of inflation rates.

First paper to consider the effect of the global financial crisis on inflation persistence.

The column this month is about CONFIG.SYS, what goes in it and how to control it. It is also about DESQview and Windows 3.0. If this column reads like a computer‐based adventure game or quest, it is because the last two months have seemed like that.

Microsoft Windows 3.0 has finally arrived. It was, by all accounts, a difficult birth, accompanied by klieg lights and hoopla stretching years into the past. In many respects, Windows 3.0 was very much like dBASE IV. Both Windows and dBASE IV shipped early versions that didn't work well. Both were embroiled in controversy and promised more than they could offer. They endured a prolonged period of ‘vaporware’ status and were from leading companies.

To explore the value in reminiscing about past festivals as a potential way of improving wellbeing in socially isolated times.

The paper uses previous research on reminiscence, nostalgia and wellbeing to underpin the analysis of self-recorded memory narratives. These were gathered from 13 pairs of festivalgoers during Covid-19 restrictions and included gathering their individual memories and their reminiscences together. The participant pairs were a mix of friends, family and couples who had visited festivals in the UK, Finland and Denmark.

Four key areas that emerged through the analysis were the emotions of nostalgia and anticipation, and the processes of reliving emotions and bonding through memories.

Future studies could take a longitudinal approach to see how memory sharing evolves and the impact of this on wellbeing. The authors also recommend undertaking similar studies in other cultural settings.

This study findings have implications for both post-festival marketing and for the further development of reminiscence therapy interventions.

The method provides a window into memory sharing that has been little used in previous studies. The narratives confirm the value in sharing memories and the positive impact this has on wellbeing. They also illustrate that this happens through positive forms of nostalgia that centre on gratitude and lead to hope and optimism. Anticipation, not emphasised in other studies, was also found to be important in wellbeing and was triggered through looking back at happier times.

Because of the special “State of the States” issue of Library Hi Tech and other circumstances beyond my control, the four quarterly “Comp Lit” compilations for 1996 appear here in a single and possibly peculiar chunk. A lot changes in a year of personal computing, but on reflection it seemed useful to include the citations and comments as I originally wrote them.