bluuebunny/crossref_metadata_2025 huggingface dataset:
The Future of Family Planning Programs
Authors: Caldwell John C. , Phillips James F. , Barkat‐e‐Khuda
Published: December 2003

National family planning programs have been an important instrument in accelerating global fertility decline and in restricting ultimate world population to a level probably below ten billion. They began to come into being after 1950 and will probably go out of existence in most of the world's regions by 2050. The archetypal programs were instituted in Asia and North Africa. The end of the twentieth century is an appropriate half‐way mark at which to evaluate the twentieth‐century programs and to assess what changes in them will be needed for the twenty‐first century. Some changes are necessary because dramatic events have occurred: (1) long‐term replacement‐level fertility has been attained in most of East Asia and some of Southeast Asia, and accordingly, some programs there are being phased out; (2) mainland South Asian fertility has been slower to decline; (3) international donor funding is diminishing and may not be significant during much of the twenty‐first century; (4) the 1994 International Conference on Population and Development held in Cairo called for a radical change in programs away from demographic aims and toward reproductive health and the improvement of the situation of women; and (5) the future family planning frontier will be sub‐Saharan Africa, for which radically new types of programs may have to be developed. These issues were discussed in January 2000 at a conference held in Dhaka, Bangladesh. A selection of contributions to the conference is published here. This article provides an overview of the issues based partly on this selection and partly on the discussions that took place at the conference.
United Nations Population Conferences: Shaping the Policy Agenda for the Twenty‐first Century
Authors: Finkle Jason L. , McIntosh C. Alison
Published: December 2003

Population conferences have evolved through three overlapping stages, each stage reflecting a different perspective on the relationship between national policy formulation and the international system. Initially, at Rome in 1954 and in Belgrade in 1965, participants were invited on the basis of their expertise and were not expected to represent their governments. By the time of the Bucharest Conference in 1974, the United Nations, in an attempt to give conferences a greater role in shaping population policy and to inspire member governments to show greater concern for their own population problems, decided that conferences would be intergovernmental gatherings and that national delegations would be selected by governments. The effect of this change was that governments gave less weight to scientific expertise and, conversely, greater weight to political and bureaucratic considerations. At the present time, although conferences remain intergovernmental gatherings, the door has been opened for nongovernmental organizations–civil society–to play a more active role in the conference process and in deliberations. As conferences have become more inclusive, their focus has veered from what has conventionally been regarded as population concerns. The changing composition of participants at UN conferences has had the effect of altering the policy agenda in the international population field and, as some have argued since Cairo, has redefined the meaning of population. Conferences in the twenty‐first century likely will be compelled to confront diverse demographic problems in addition to social issues demanding the attention of the political system at every level.
Future Trends in Contraceptive Prevalence and Method Mix in the Developing World
Authors: Bongaarts John , Johansson Elof
Published: December 2003

This study reviews existing methodologies for projecting future trends in contraception, evaluates the validity of the assumptions underlying these projections, proposes methodological improvements, and assesses the prospects for new methods of contraception in the coming decade. Demand for contraception can be expected to continue to rise rapidly for the next few decades as populations continue to grow and fertility declines to approach replacement level. As a result of these trends, the number of contraceptive users in the developing world is expected to rise from 549 to 816 million during the next 25 years, according to the most recent UN projection. An examination of the projection methodology found it to be reasonable. Projecting the future distribution of specific contraceptive methods is more difficult. Method choice is affected by trends in several factors, including access to different methods, user characteristics, and technology. The procedure employed by the Futures Croup to project method mix was found to be less than optimally designed, and a new methodology is, therefore, proposed.
Policy Implications of the Next World Demographic Transition
Authors: Harbison Sarah F. , Robinson Warren C.
Published: December 2003

Although the world demographic transition from high to low fertility appears to be nearing its completion, observed in perspective, this is the latest in a series of such transitions stretching back into prehistory. A stable new equilibrium is far from inevitable; indeed, it is unlikely. Many countries are experiencing below‐replacement‐level fertility, and this trend is spreading. Couples are now able to choose their family size, free of the traditional pressures to bear children that was characteristic of most traditional societies. In fact, most societal pressures for the last generation have been distinctly antinatalist, in response to the enormous attention paid by the media to the “population bomb” agenda. This antinatalist attitude is changing, however, and what seems more likely than either a stationary or declining world population is a new growth cycle reflecting a resurgence of fertility as a response to growing material affluence and potential technological mastery of environmental challenges. Societal pressures and policies will play a role in this transition as they did in earlier ones.
Transforming Family Planning Services in the Latin American and Caribbean Region
Authors: Helzner Judith F.
Published: December 2003

The 1994 International Conference on Population and Development held in Cairo has generated widespread commitment to changing family planning programs from categorical and medically focused service organizations to reproductive health initiatives that embrace a wide range of social and human services. This article uses qualitative data analysis to review the experience of nine family planning association projects in the Latin American and Caribbean region that have made a successful organizational transition from services focused on family planning to a gender‐based and sexual health approach. A conceptual framework is proposed, including factors external to the organization. Factors that can promote a pilot intervention's becoming fully institutionalized include: the need for commitment from high‐level staff and members of the board of directors, the creation of partnerships with other agencies, and an emphasis on monitoring and evaluation. Lessons from this experience and their potential relevance to other settings are reviewed and discussed.
Facilitating Large‐scale Transitions to Quality of Care: An Idea Whose Time Has Come
Authors: Simmons Ruth , Brown Joseph , Díaz Margarita
Published: December 2003

In the field of reproductive health, investigation of the transfer of knowledge gained from demonstration and pilot projects to large public‐sector programs typically has not been considered a relevant domain for research or other investigation. This article draws on a range of research in the social sciences and presents two frameworks for understanding the critical attributes of successful expansion of small‐scale innovations. Seven key lessons are developed using examples from family planning where scaling up was an explicit objective, including the early Taichung Study of Taiwan, the Chinese Experiment in Quality of Care, the Bangladesh MCH‐FP Extension Project, the Navrongo Project in Ghana, and the Reprolatina Project in Brazil. Unless small, innovative projects concern themselves from the outset with determining how their innovations can be put to use on a larger scale, they risk remaining irrelevant for policy and program development.
Africa: The New Family Planning Frontier
Authors: Caldwell John C. , Caldwell Pat
Published: December 2003

Sub‐Saharan Africa will be the family planning frontier of the twenty‐first century. Fertility levels and population growth rates are still high, and family planning programs suited to the region are still being developed. Nevertheless, by the end of the twentieth century, fertility transition was under way in Southern Africa and a few countries elsewhere. Successful regional family planning in the twenty‐first century will depend upon stronger political leadership, the development of family planning programs that meet the needs of all segments of society and not only currently married women, assistance to the market, and a recognition of the central importance of hormonal methods, especially injectables. Problems include stagnation in economic growth and in child mortality decline, as well as the persistence of the AIDS epidemic.
Reconsidering the Doorstep‐delivery System in the Bangladesh Family Planning Program
Authors: Arends‐Kuenning Mary
Published: December 2003

The government of Bangladesh is currently testing and implementing strategies to change its family planning program from a reliance on field‐workers who conduct home visits to a conventional fixed‐site delivery system. Researchers have made two suggestions: First, the program should encourage women to switch from nonclinical methods delivered by family planning workers to more cost‐effective clinical methods such as sterilization, and second, field‐workers should not be resupplying nonclinical methods, but should focus their attention on motivating nonusers to practice contraception. Longitudinal data from the Maternal and Child Health‐Family Planning Extension Project of the International Centre for Diarrhoeal Disease Research, Bangladesh, are analyzed to show that a better strategy might be to target visits to women according to their educational level and area of residence. For uneducated women living far from clinics, access to contraceptives is likely to be a problem, and home visits for resupply might have a larger impact on the contraceptive prevalence rate than would field‐workers'visits to motivate nonusers.
China's Family Planning Policy: An Overview of Its Past and Future
Authors: Attané Isabelle
Published: December 2003

This article provides a broad overview of China's family planning policy during the last three decades, highlighting key trends and goals of the program at national and provincial levels. It focuses on the administrative, economic, cultural, and other factors that have helped or hindered the family planning effort and reviews the impact of the program on the provincial population. A key question is whether the policy of strict fertility control will remain relevant and enforceable as population growth slows, as controlling private life becomes increasingly problematic for the government, and as new demographic problems (for example, aging) emerge.
Asia's Family Planning Programs as Low Fertility Is Attained
Authors: Jones Gavin , Leete Richard
Published: December 2003

The dramatic demographic changes in Asia during the three decades from 1970 to the end of the twentieth century were matched by major changes in government population policies and programs, fertility declines occurred in widely different economic, sociocultural, and political settings. The extent to which they were attributable to family planning programs, established in most countries of the region by 1970, is hotly debated. The 1970s were the heyday of family planning programs, which were created in a climate of urgency because of concerns over the “population explosion.” Issues faced by programs at that time are discussed. Over time, programs generally have moved to a simpler “service” approach. As increasing numbers of countries reach replacement‐level fertility, and as policies are formed against the background of the 1994 International Conference on Population and Development held in Cairo, the role of family planning programs is increasingly debated and questioned. This article examines the responses of Asian countries and the population challenges that remain.
Monitoring Contraceptive Continuation: Links to Fertility Outcomes and Quality of Care
Authors: Blanc Ann K. , Curtis Siân L. , Croft Trevor N.
Published: December 2003

This study examines the fertility consequences of contraceptive discontinuation, describes cross‐national variation in continuation rates, and assesses the usefulness of the contraceptive discontinuation rate as a summary outcome indicator of quality of care. In the 15 countries included in this analysis, the total fertility rate would be between 28 and 64 percent lower if the births following discontinuations that were not the result of a desire to become pregnant had not occurred. The all‐method discontinuation rate for quality‐related reasons emerges as the most likely candidate for a summary measure of quality of care. Within a year of starting use of a method, between 7 and 27 percent of women cease to practice contraception for reasons related to the quality of the service environment. The results imply that as fertility declines, family planning programs would profit from a shift in emphasis from providing methods to new clients toward providing services to reduce discontinuation rates.
The Impact of the Navrongo Project on Contraceptive Knowledge and Use, Reproductive Preferences, and Fertility
Authors: Debpuur Cornelius , Phillips James F. , Jackson Elizabeth F. , Nazzar Alex , Ngom Pierre , Binka Fred N.
Published: December 2003

The Navrongo Community Health and Family Planning Project is a quasi‐experimental study designed to test the hypothesis that introducing health and family planning services in a traditional African societal setting will introduce reproductive change. This article presents the impact of the initial three years of project exposure on contraceptive knowledge, awareness of supply sources, reproductive preferences, contraceptive use, and fertility. Findings show that knowledge of methods and supply sources increased as a result of exposure to project activities and that deployment of nurses to communities was associated with the emergence of preferences to limit childbearing. Fertility impact is evident in all treatment cells, most prominently in areas where nurse‐outreach activities are combined with strategies for involving traditional leaders and male volunteers in promoting the program. In this combined cell, the initial three years of project exposure reduced the total fertility rate by one birth, comprising a 15 percent fertility decline relative to fertility levels in comparison communities.
Changing Patterns of Mongolian Fertility at a Time of Social and Economic Transition
Authors: Aassve Arnstein , Altankhuyag Gereltuya
Published: December 2003

In 1989, after a long period of socialist rule, Mongolia initiated a democratization process of its political system together with a transition toward a market economy. This study examines how changes in socioeconomic conditions in Mongolia have affected fertility patterns in recent times. It also provides an outline of changes that have taken place in terms of pronatalist policies. Data are drawn from the Reproductive Health Survey of Mongolia conducted in 1998. Among the older cohort, the relationship between economic activity and fertility is inverse but weak, whereas among the younger cohort, the economic downturn has had a strongly depressing effect on fertility. Important effects of micro‐level variables, including education and housing, are also noted. The findings suggest that the fertility decline observed for the older cohorts is part of the first demographic transition, in which the collapse of pronatalist policies was influential
The Impact of Female Genital Cutting on First Delivery in Southwest Nigeria
Authors: Slanger Tracy E. , Snow Rachel C. , Okonofua Friday E.
Published: December 2003

To date, data linking obstetric morbidity to female genital cutting in populations with less severe types of cutting have been limited to case reports and speculation. In this cross‐sectional study, 1,107 women at three hospitals in Edo State, Nigeria, reported on their first‐delivery experiences. Fifty‐six percent of the sample had undergone genital cutting. Although univariate analyses suggest that genital cutting is associated with delivery complications and procedures, multivariate analyses controlling for sociodemographic factors and delivery setting show no difference between cut and noncut women's likelihood of reporting first‐delivery complications or procedures. Whereas a clinical association between genital cutting and obstetric morbidity may occur in populations that have undergone more severe forms of cutting, in this setting, apparent associations between cutting and obstetric morbidity appear to reflect confounding by social class and by the conditions under which delivery takes place.
Spousal Communication and Family Planning Behavior in Navrongo: A Longitudinal Assessment
Authors: Bawah Ayaga A.
Published: December 2003

The poor performance of most family planning programs in the 1980s, especially in sub‐Saharan Africa, generated concern among researchers and led to a quest for explanations. In most countries, the alienation of men from participation in these programs was subsequently identified as one of the major causes, a finding that led researchers to redirect their attention to couples instead of individuals as the focus of such programs. Lack of spousal communication about family planning was identified as one reason for the low level of contraceptive use among women. Subsequent research has persistently demonstrated a positive relationship between spousal communication and contraceptive use. Most prior studies on this topic have been based on cross‐sectional data, so that whether the identified relationships are causal remains unclear. Does communication, in fact, predict contraceptive use, or does the use of contraceptives generate communication among couples? This study addresses the question of causality by using longitudinal data from the Navrongo Health Research Centre panel survey. Results from both cross‐sectional and longitudinal analysis demonstrate that spousal communication does, indeed, predict contraceptive behavior, even when other factors are controlled.
Reducing Unplanned Pregnancy and Abortion in Zimbabwe Through Postabortion Contraception
Authors: Johnson Brooke R. , Ndhlovu Singatsho , Farr Sherry L. , Chipato Tsungai
Published: December 2003

In many countries, women treated for complications from spontaneous or unsafely induced abortion lack access to contraceptive services. As a result, many of them soon have a subsequent unplanned pregnancy or a repeat abortion, placing their health at increased risk. This report presents the results of a prospective intervention study on postabortion family planning conducted in the two largest public hospitals in Zimbabwe. Women at Harare Central Hospital, in the capital, received a postabortion family planning intervention, and Mpilo Central Hospital, in Bulawayo, served as the control site. The study cohort was 982 women, 527 of whom were followed for a 12‐month period. During the follow‐up period, significantly more women used highly effective methods of contraception, significantly fewer unplanned pregnancies occurred, and fewer repeat abortions were performed at the intervention site than at the control site. These results offer compelling evidence that ward‐based contraceptive services provided to women treated for incomplete abortion can significantly reduce subsequent unplanned pregnancies. The results also suggest that postabortion family planning services can reduce the incidence of repeat abortion.
The Prevalence of Reproductive Tract Infections in Hue, Vietnam
Authors: Thi Lien Phan , Elias Christopher , Thi Loi Nguyen , Thi Chi Bui , Hua Phuc Nguyen , Gardner Michelle
Published: December 2003

A study was conducted in central Vietnam to measure the prevalence of reproductive tract infections among clients of a family planning clinic, and to determine the usefulness of simple, clinic‐based diagnostic tests. The prevalence of such infections was moderate, with the majority being endogenous. Few cases of cervical infection were identified, and no clinical or sociodemographic variables proved to be good predictors of such infection. Most vaginal infections could be identified through simple, clinic‐based diagnostic tests, although further research into the cost‐effectiveness of establishing and maintaining these services would be useful. Comparison of the results from laboratory tests and the presumptive diagnosis of the clinician indicate that the current practice of presumptive treatment is leading to significant overtreatment. Use of the World Health Organization flowcharts would reduce the overtreatment of vaginal infection but not of cervical infection. The importance of adapting the flowcharts to local epidemiology is highlighted.
Maternal Mortality in India: An Update
Authors: Bhat P. N. Mari
Published: December 2003

This study presents estimates of maternal mortality for India from two indirect procedures, the sisterhood method and a regression method involving sex differentials in adult mortality, and compares them with estimates available from other sources. The sisterhood method is applied to the data collected in a human development survey that covered all rural areas of India in 1994, while the latter method is applied to the data on mortality and fertility rates from India's Sample Registration System. The level of maternal mortality for the early 1980s implied by the sisterhood method is found to be about 15 percent lower than the estimate for the same period derived from the method that uses the data on sex differentials in adult mortality. The estimate for the 1990s from the latter method is consistent, however, with the direct estimates available from the National Family Health Survey and the Sample Registration System. The study also discusses the socioeconomic differentials in maternal mortality implied by the sisterhood data, and spatial and temporal variations in maternal mortality derived from the regression method.
Is “Abortion Culture” Fading in the Former Soviet Union? Views about Abortion and Contraception in Kazakhstan
Authors: Agadjanian Victor
Published: December 2003

The Soviet legacy of widespread reliance on induced abortion is of critical importance to reproductive trends and policies in post‐Soviet nations, especially as they strive to substitute contraception for abortion. Using data from two Demographic and Health Surveys conducted in 1995 and 1999, this study analyzes and compares trends in abortion and contraception, women's attitudes toward abortion, and their perceptions of problems associated with abortion and contraception in Kazakhstan. Despite an overall decline in abortion and an increase in contraceptive use since Kazakhstan's independence in 1991, abortion has remained a prominent part of the country's reproductive culture and practices. This study shows how abortion‐related views reflect the long‐standing ethnocultural differences between the indigenous Kazakhs and Kazakhstan's residents of European roots, as the latter continue to have significantly higher levels of abortion. The study, however, also reveals the internal diversity among Kazakhs with respect to abortion experiences and views, stemming from decades of the Soviet sociocultural influence in Kazakhstan. In addition, the analysis points to some generational differences in views concerning abortion and contraception. Finally, the study demonstrates parallels in attitudes toward abortion and toward contraception, thereby questioning straightforward assumptions about the replacement of abortion with contraception.
Abortion Risk and Decisionmaking among Young People in Urban Cameroon
Authors: Calvès Anne‐Emmanuèle
Published: December 2003

This study examines the use of induced abortion among Cameroonian adolescents and young women, based on biographical data collected in 1997 among young women and men residing in Yaounde. Results suggest a high prevalence of abortion during adolescence and early adulthood (35 percent of all pregnancies reported). Although most clandestine abortions were performed by a physician or a nurse, the prevalence of abortion performed by nonmedical personnel or using unsafe methods is still high, and postabortion health complications are reported for about one‐fourth of all abortions. Logistic regression models are used to examine the effect of women's, partners', and relationships' characteristics at the time of pregnancy on the odds that a pregnancy will be terminated through abortion. The analysis shows a significant effect of school enrollment, parity, and stability and social acknowledgment of the sexual relationship on the risk of having an abortion. Young men's involvement in decisions and their motivations concerning abortion are also examined.
Menstrual Disorders in Rural Gambia
Authors: Walraven Gijs , Ekpo Gloria , Coleman Rosalind , Scherf Caroline , Morison Linda , Harlow Siobán D.
Published: December 2003

As part of a community‐based reproductive morbidity survey in rural Gambia, the prevalence and association of menstrual disorders with sociodemographic characteristics and other reproductive morbidities, and with knowledge, attitudes, and beliefs concerning menstrual problems were assessed. A questionnaire was administered by a field‐worker and by a gynecologist, who also examined the women. Semistructured interviews were conducted to assess knowledge, attitudes, and beliefs in a subsample. Of 607 menstruating women not using hormonal contraceptives, 16 percent complained to the gynecologist of irregular cycles, 14 percent of dysmenorrhea, 8 percent of spotting, and 4 percent of heavy or prolonged bleeding. Each complaint was associated with other reproductive morbidities. A minority of women with menstrual problems had sought health care, and menstruation was revealed to be a highly personal and secretive topic in this population. Menstrual disorders constitute an important unaddressed area of reproductive health service needs in developing countries for which relatively simple and inexpensive therapies are often available. Information, education, and support combined with clinical management of menstrual problems should be core elements of reproductive health programs.
Packaging Induced Die Stresses—Effect of Chip Anisotropy and Time-Dependent Behavior of a Molding Compound
Authors: van Driel W. D. , Janssen J. H. J. , Zhang G. Q. , Yang D. G. , Ernst L. J.
Published: December 2003

This paper investigates the effect of the anisotropic behavior of the die and the time- and temperature-dependent behavior of epoxy molding compound on the packaging induced stresses for a quad flat package. Finite element (FE) simulations using isotropic and anisotropic properties of the die are carried out, respectively, and the results are compared. Creep experiments were performed at different temperatures ranging from −65°C to 230°C to obtain the long-term master curves and the related shift factors for the creep compliance of the molding compound. FE models which incorporate the viscoelastic constitutive relation of the material are constructed to simulate the thermo-mechanical stresses caused by the packaging processes. The influences of both the chip anisotropy and the viscoelastic behavior of the molding compound on the packaging induced stresses are discussed.
Thermal Stress and Deflection Analysis of a Glass Window (Circular Plate) Elastically Restrained Along its Edge in a Photonic Device
Authors: Lau John H. , Erasmus Steve , Zou Yida
Published: December 2003

An exact analysis is presented for the stresses and deflections of circular plates (glass windows) elastically restrained along its edge in a photonic device’s housing subjected to the pressure and temperature loadings. Dimensionless curves and charts are also provided for engineering practice convenience. These charts show the interactions of the deflection, stress, temperature, pressure, linear spring constant, rotational spring constant, geometry of the glass windows, and the Young’s modulus, Poisson’s ratio, thermal coefficient of expansion, geometry, stress-optical coefficient, and birefringence of glass materials. The results presented herein should be useful for designing glass windows for shipping, storing, handling, functioning, and reliability.
Predicting critical dimension uniformity in advanced electron-beam projection lithography masks
Authors: Cotte Eric P. , Mikkelson Andrew R. , Matesanz Oscar , Engelstad Roxann L. , Lovell Edward G. , Reu Phillip L.
Published: December 2003

Meeting the stringent budgets for both overlay errors and critical dimensions (CDs) for the insertion of next-generation lithographies requires that the sources of mask-related distortions be identified and minimized. Such sources include the mask fabrication process, electron-beam patterning, and exposure conditions. This article describes numerical simulations to characterize CD nonuniformities for the stencil format of the electron-beam projection lithography PREVAIL mask. Finite element (FE) submodeling and equivalent modeling techniques were used to investigate CD uniformity for a worst-case scenario. Whereas a global model is sufficient to predict mask overlay errors, submodeling and statistical analyses are necessary to characterize mask CD errors. The FE simulations illustrate that CD nonuniformities (from mask fabrication) can be limited to 1.0 nm, if the maximum membrane prestress is monitored and controlled. Such results comply with the CD error budgets set for the sub-65-nm lithography nodes.
Patterning of gold film on muscovite mica by using a helium-metastable atom beam and an octanethiol self-assembled monolayer
Authors: Ju X. , Kurahashi M. , Suzuki T. , Yamauchi Y.
Published: December 2003

Using a helium-metastable atom beam and an octanethiol (OT) self-assembled monolayer (SAM), we carried out atom lithography to the gold film on muscovite mica having a flat surface. A large intact area and a clear pattern with a nanoscale width ∼80–100 nm of the etched step was obtained. The gold surface, as well as the surface of the mica substrate, was flat. From the analysis of the roughness, appreciable gold islands were not detected in the area exposed to the He* atom beam. This finding demonstrates that the OT SAMs on atomically flat surfaces can be used as a resist for exposure to metastable-atom beams.
Fabrication of subwavelength surface structures combining self-assembled masking layer with plasma etching techniques
Authors: Oesterschulze E. , Georgiev G. , Müller-Wiegand M. , Georgieva A. , Ludolph K.
Published: December 2003

A lithography-free method for producing periodic and nonperiodic surface structures is presented. It combines self-assembly of masking particles with well established plasma etching techniques known from microelectromechanical system technology. The method is generally applicable to bulk as well as layered materials. In our experiments, layers of glass spheres of different diameter were assembled on the sample surface forming a mask against plasma etching. Silicon surface structures with periodicity of 500 nm and feature dimensions of 20 nm were produced in this way. Thermal oxidation of the so structured silicon substrate offers the capability to vary the fill factor of the periodic structure owing to volume expansion during oxidation but also to define silicon dioxide surface structures by selective plasma etching. Similar structures can be simply obtained structuring silicon dioxide layers on silicon. The method offers a simple route, e.g., for photonic crystal fabrication.
Focused ion beam milling of diamond: Effects of H2O on yield, surface morphology and microstructure
Authors: Adams D. P. , Vasile M. J. , Mayer T. M. , Hodges V. C.
Published: December 2003

The effects of H2O vapor introduced during focused ion beam (FIB) milling of diamond(100) are examined. In particular, we determine the yield, surface morphology, and microstructural damage that results from FIB sputtering and H2O-assisted FIB milling processes. Experiments involving 20 keV Ga+ bombardment to doses ∼1018 ions/cm2 are conducted at a number of fixed ion incidence angles, θ. For each θ selected, H2O-assisted ion milling shows an increased material removal rate compared with FIB sputtering (no gas assist). The amount by which the yield is enhanced depends on the angle of incidence with the largest difference occurring at θ=75°. Experiments that vary pixel dwell time from 3 μs to 20 ms while maintaining a fixed H2O gas pressure demonstrate the additional effect of beam scan rate on yield for gas-assisted processes. Different surface morphologies develop during ion bombardment depending on the angle of ion incidence and the presence/absence of H2O. In general, a single mode of ripples having a wave vector aligned with the projection of the ion beam vector forms for θ as high as 70°. H2O affects this morphology by lowering the ripple onset angle and decreasing the ripple wavelength. At high angles of incidence (θ>70°) a step/terrace morphology is observed. H2O-assisted milling at θ>70° results in a smoother stepped surface compared with FIB sputtering. Transmission electron microscopy shows that the amorphized thickness is reduced by 20% when using H2O-assisted FIB milling.
Fabrication of nickel oxide nanostructures by atomic force microscope nano-oxidation and wet etching
Authors: Hsu Ju-Hung , Lai Hsin-Wen , Lin Heh-Nan , Chuang Chia-Chih , Huang Jin-Hua
Published: December 2003

We report the fabrication of nickel oxide nanostructures by atomic force microscope nano-oxidation and subsequent wet etching. By applying a negative bias to a conductive tip, nickel oxide patterns are first created by the process of nano-oxidation. The unoxidized nickel film is then etched away in a diluted nitric acid solution. Auger electron spectroscopy measurements confirm the complete removal of the nickel film and the preservation of the oxide patterns. Nickel oxide nanodots with diameters as small as 100 nm are reliably produced by the present method.
Fabrication and characterization of a SiGe double quantum dot structure
Authors: Qin H. , Yasin Shazia , Williams D. A.
Published: December 2003

Solid-state quantum dots, in which the charge and spin of excess carriers are controllable, are strong candidates for future nanoelectronics and quantum information processing. Devices based on SiGe are compatible with conventional silicon complementary metal–oxide–semiconductor processing, which allows for large-scale integration. The fabrication of SiGe double quantum dots using electron beam lithography and reactive ion etching is described. Devices are characterized electrically at cryogenic temperatures and the mixing of two microwave signals is demonstrated.
Mask process proximity correction for next-generation mask fabrication
Authors: Ho Kim Soon , Choi Sung-Woon , Sohn Jung-Min , Rak Park Jong
Published: December 2003

As the requirements for minimum resolution on masks continue to tighten, performing proximity correction for mask making will be even more necessary. Mask process correction MPC with a two-Gauss kernel can be used in order to analyze and correct mask process proximity effects. From measured critical dimension (CD) linearity and two-Gauss model, the process kernel parameters α (range of spot size), β (range of dry-etching and development process) and η′ (contribution ratio of β over α) were extracted, and MPC was performed on the layout of linearity patterns by applying biases to the edge elements of the design. The CD linearity was dramatically improved even for small pattern sizes; the CD values of isolated spaces, lines and spaces, contacts, and isolated lines varied only by 10 nm for 1 μm down to 100 nm feature size pattern. The MPC concept demonstrated in this article has the potential to push the mask-making resolution limit to an even smaller size than 100 nm patterns without any deterioration in CD linearity.
Photoelectronic analog-to-digital conversion using miniature electron optics: Basic design considerations
Authors: Pease R. Fabian , Ioakeimidi Katerina , Aldana Rafael , Leheny Robert
Published: December 2003

There is a continuing need for faster and more precise analog-to-digital converters (ADCs). State of the art ADCs have reached the 10 gigasamples/second (GS/s), 6–12 bit performance. We investigate an implementation of a 100 GS/s 4–6 bit ADC. The use of a cathode ray tube for analog-to-digital conversion was first described in the 1940s. The basic idea is that a bunch of electrons passing through an electric deflection system is directed to a specific detector whence a digital code word emanates. Thus the electron bunch samples the analog deflecting voltage which is then quantized according to the position of the detector receiving the bunch. The most fundamental limit to the number of distinguishable voltage levels is the ratio of the deflecting impulse to the momentum spread due to diffraction of the electron beam. This should allow up to 12 bits at 100 GS/s. At a more practical level the bit resolution and sampling frequency are limited by the brightness of the beam, the uncertainty in the time of emission of each bunch and by the maximum power needed to generate the analog voltage used to deflect the beam. For 50 V deflecting voltage and 100 fs timing uncertainty we should be able to achieve 4–5 bits for a 50 GHz bandwidth on the analog voltage (100 GS/s).
Focused ion beam created periodic structures on tapered optical fibers
Authors: Hodzic Vildana , Orloff Jon , Davis Christopher
Published: December 2003

High resolution focused ion beams have been used to create optical structures and to create high quality optical surfaces. We report here the use of Ga+ and B+ ion beams to produce gratings on optical fibers by micromachining and direct implantation, respectively. In both cases local periodic perturbations of the cladding refractive index were introduced in the reduced diameter (waist) region of biconically tapered single-mode optical fibers. By micromachining we produced short grooves perpendicular to the fiber axis and boron implantation gave a phase grating in the cladding. Both structures demonstrate a wavelength dependent throughput and are highly sensitive to the environment in the waist region, which makes them potentially applicable in sensors as well as in optical communication networks.
Fabrication of 12 nm electrically variable shallow junction metal–oxide–semiconductor field effect transistors on silicon on insulator substrates
Authors: Henschel W. , Wahlbrink T. , Georgiev Y. M. , Lemme M. , Mollenhauer T. , Vratzov B. , Fuchs A. , Kurz H.
Published: December 2003

Electrically variable shallow junction metal–oxide–semiconductor field effect transistors on silicon on insulator have been fabricated to evaluate the suitability of fabrication processes on a nanoscale. In addition, the limits of scalability have been explored reducing gate lengths down to 12 nm. Specific attention has been paid to the overlay accuracy as required for the fabrication of these double gate structures. The superior quality of hydrogen silsesquioxane (HSQ) as electron beam resist and as mask material is demonstrated. The transistor fabricated exhibits extremely low leakage currents and relatively high on currents. The 8 orders of magnitude difference between the on and off states demonstrates conclusively large potentials for metal–oxide–semiconductor structures with critical dimensions in the 10 nm regime.
Formation of a few nanometer wide holes in membranes with a dual beam focused ion beam system
Authors: Schenkel T. , Radmilovic V. , Stach E. A. , Park S.-J. , Persaud A.
Published: December 2003

When nanometer-scale holes (diameters of 50 to a few hundred nm) are imaged in a scanning electron microscope (SEM) at pressures in the 10−5 to 10−6 Torr range, hydrocarbon deposits build up and result in the closing of holes within minutes of imaging. Additionally, electron or ion beam assisted deposition of material from a gas source allows the closing of holes with films of platinum or tetraethylorthosilicate oxide. In an instrument equipped both with a focused ion beam, and a SEM, holes can be formed and then covered with a thin film to form nanopores with controlled openings, ranging down to only a few nanometers, well below resolution limits of primary beams.
Line edge roughness of sub-100 nm dense and isolated features: Experimental study
Authors: Ma Yuansheng , Tsvid G. , Cerrina Franco
Published: December 2003

The nanoscale roughness in patterned images has become a crucial problem in advanced lithography. We have designed and implemented an experiment to study the line edge roughness (LER) for both dense line and space (DEN) and isolated (ISO) lines. The resist selected is UV-6 (a positive tone chemically amplified resist (CAR) from Shipley), and as a comparison, non-CAR such as poly(methylmethacrylate) (PMMA) is also measured. After development, the resist is analyzed using high resolution scanning electron microscopy (SEM) (LEO 1550 VP). An in-house made software is used for LER estimations. Our results indicate that DEN lines appear to be rougher than ISO lines given the same dose and nominal modulation. This is fully accounted by the lower modulation of DEN patterns caused by proximity effects. In addition, CAR resists like UV-6 are much rougher than non-CARs such as PMMA. A simple percolation model based on stochastic modeling predicts the observed trends.
Stochastic modeling of high energy lithographies
Authors: Han Geng , Khan Mumit , Cerrina Franco
Published: December 2003

We present our progress in developing a comprehensive stochastic model that taking into account the energy redistribution from the incoming radiation, the location of the chemical events, the type of chemical changes, and the resist development. A study of line edge roughness extracted from the simulation for 50 nm lines is discussed.
DNA microarrays: An imaging study
Authors: Kim C. , Li M. , Lowe A. , Venkataramaiah N. , Richmond K. , Kaysen J. , Cerrina F.
Published: December 2003

DNA chips are used to study the composition of genetic material. We report the results of an experimental study of the synthesis of DNA microarrays using a maskless photodeprotection process. In these “chips,” the quality of the final product is dependent on the type and frequency of errors in the synthesis of the oligonucleotides. Contrary to photoresist, the photochemistry is linear and thus more prone to the introduction of defects. To understand and characterize the exposure process, we have developed a theoretical image formation model based on standard lithographic modeling tools. Experimentally, we have used a microarray synthesizer similar to that described in (Ref. 1), but using an argon ion laser as radiation source. To characterize the process, we have acquired aerial images using a CCD camera, a photosensitive film, and fluorescence image of a T-base monomer. We will discuss the imaging properties of the optical system, the models used to analyze the data and the relation between measured images and DNA stepwise synthesis yield.
Initial results of a 50 kV electron beam writer EBM-4000 for a 90 nm node photomask
Authors: Murooka Ken-ichi , Hattori Kiyoshi , Iizuka Osamu
Published: December 2003

We have developed new 50 kV electron beam writer, EBM-4000, which is designed to fulfill the requirements for the 90 nm node mask. EBM-4000 makes use of the assets of our previous model, but major modifications are carried out on electron optics, writing circuits, and vacuum system. The written patterns are evaluated about CD uniformity, image placement accuracy, and throughput. The results indicate that CD uniformity and image placement accuracy meet the requirements for 90 nm node photomask, and EBM-4000 has a potential to extend its feasibility to 65 nm node photomask with acceptable throughput.
Sublithographic nanofabrication technology for nanocatalysts and DNA chips
Authors: Choi Yang-Kyu , Lee Joon Sung , Zhu Ji , Somorjai Gabor A. , Lee Luke P. , Bokor Jeffrey
Published: December 2003

We describe parallel processes for nanometer pattern generation on a wafer scale with resolution comparable to the best electron beam lithography. Sub-10 nm linewidth is defined by a sacrificial ultrathin film deposited by low pressure chemical vapor deposition (LPCVD), in a process similar to formation of gate sidewall spacers in CMOS processing. We further demonstrate a method called iterative spacer lithography (ISL), in which the process is repeated multiple times with alternating materials in order to multiply the pattern density. Silicon structures with sub-10 nm width fabricated by this process were used as a mold in nanoimprint lithography and lift-off patterning of sub-30 nm platinum nanowires for use in experiments on chemical catalysis. We also demonstrate a similar process called reversed spacer lithography (RSL) to form sub-10 nm fluid channels in poly-Si. This nanogap fluid channel device was used for label-free detection of DNA hybridization based on electrical sensing of dielectric changes in the gap.
Focused ion beam-induced fabrication of tungsten structures
Authors: Ishida M. , Fujita J. , Ichihashi T. , Ochiai Y. , Kaito T. , Matsui S.
Published: December 2003

Sidewall morphology on three-dimensional (3D) tungsten structures grown with focused ion beam-induced chemical vapor deposition (FIB-CVD) using tungsten hexacarbonyl [W(CO)6] was improved with a milling process by using FIB treatment subsequent to growth. As a result, Young’s modulus was measured at 300 GPa at maximum and density was measured at 13.0×103 kg/m3. Young’s modulus increased 35% after heat treatment at 600 °C in a vacuum while density did not change. Transmission electron microscopy revealed crystallization of tungsten trioxide after the heat treatment.
Preparations for extreme ultraviolet interferometry of the 0.3 numerical aperture Micro Exposure Tool optic
Authors: Goldberg Kenneth A. , Naulleau Patrick P. , Denham Paul E. , Rekawa Senajith B. , Jackson Keith H. , Liddle J. Alexander , Harteneck Bruce , Gullikson Eric , Anderson Erik H.
Published: December 2003

An at-wavelength interferometer is being created for the measurement and alignment of the 0.3 numerical aperture Micro Exposure Tool (MET) projection optic at extreme ultraviolet (EUV) wavelengths. The prototype MET system promises to provide early learning from EUV lithographic imaging down to 20 nm feature size. The threefold increase to 0.3 NA in the image-side numerical aperture presents several challenges for the extension of ultrahigh-accuracy interferometry, including pinhole fabrication and the calibration and removal of systematic error sources.