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Elevated plasma total homocysteine is an independent risk factor for cardiovascular disease and a sensitive marker of the inadequate vitamin B12 and folate insufficiency. Folate and vitamin B12 have a protective effect on cardiovascular disease. This population based study was conducted to evaluate the plasma total homocysteine, folate, and vitamin B12 in healthy Iranian individuals.
This study was a part of the Cardiovascular Risk Factors Survey in the Population Lab Region of Tehran University has been designed and conducted based on the methodology of MONICA/WHO Project. A total of 1214 people aged 25–64 years, were recruited and assessed regarding demographic characteristics, homocysteine, folate, and vitamin B12 levels with interview, questionnaires, examination and blood sampling. Blood samples were gathered and analyzed according to standard methods.
The variables were assessed in 1214 participants including 428 men (35.3%) and 786 women (64.7%). Age-adjusted prevalence of hyperhomocysteinemia (Hcy≥15 μmol/L) was 73.1% in men and 41.07% in women (P < 0.0001). Geometric mean of plasma homocysteine was 19.02 ± 1.46 μmol/l in men and 14.05 ± 1.45 μmol/l in women (P < 0.004) which increased by ageing. Age-adjusted prevalence of low serum folate level was 98.67% in men and 97.92% in women. Age-adjusted prevalence of low serum vitamin B12 level was 26.32% in men and 27.2% in women. Correlation coefficients (Pearson's r) between log tHcy and serum folate, and vitamin B12 indicated an inverse correlation (r = -0.27, r = -0.19, P < 0.0001, respectively).
These results revealed that the prevalence of hyperhomocysteinemia, low folate and vitamin B12 levels are considerably higher than other communities. Implementation of preventive interventions such as food fortification with folic acid is necessary.
Homocysteine (Hcy) is a nonessential sulfur-containing amino acid formed from the demethylation of an essential amino acid, methionine [1]. Plasma folate and vitamin B12 influence homocysteine metabolism as cosubstrate and cofactor, respectively [2]. Elevated plasma total homocysteine (tHcy) has been linked both to the inadequate status of vitamin cofactors (i.e. folate, vitamin B12 and B6) and to genetic defects in enzymes involved in homocysteine metabolism [3]. Genetic causes are mostly defects in the enzymes that control homocysteine metabolism. It is now believed that metabolism of homocysteine may be race and ethnic dependent [4].
Elevated plasma levels of homocysteine increase the risk for atherosclerosis, stroke, myocardial infarction, possibly Alzheimer's disease, cognitive impairment in the elderly, birth defects in pregnant women, and all-cause mortality [5]. Besides, hyperhomocysteinemia (HHcy) may induce changes in DNA that may result in procarcinogenic effects [6]. On one hand, plasma homocysteine is a very sensitive marker of folate and vitamin B12 status; plasma homocysteine levels are inversely related to plasma levels of these substances. The increase in homocysteine level occurs long before classic deficiency of folate and vitamin B12 become evident [7]. Inadequate levels of these vitamins have important health consequences that may be independent of their role in homocysteine metabolism [8]. Folate and vitamin B12 status has been related to the occurrence of neural tube defects. Other potential manifestations of folate deficiency include neurological and neuropsychiatric disorders, and preneoplastic conditions. Furthermore, folate deficiency has been associated with a predisposition to atherosclerotic cardiovascular disease [9,10]. Folate status may be negatively influenced by inadequate intake, genetic polymorphisms and interactions with various drugs [6]. Folate and vitamin B12 have a protective association with cardiovascular disease that can be partly explained by mechanisms independent of homocysteine, as suggested by several recent studies [11,12]. On the other hand, folate and cobalamin status are important modifiable determinants of plasma total homosysteine in the general population, and negative relations between plasma total homocysteine concentrations and these vitamins are observed even within their established normal and subnormal concentration ranges [13]. Testing for hyperhomocysteinemia may therefore be useful to assess the nutritional status in humans. Estimation of the proportion of cases with high homocysteine concentrations that can be attributed to inadequate vitamin status is complicated by the lack of a standard definition of a high total homocysteine concentration. In the absence of a definition based on increased risk for an adverse health outcome, such as vascular disease, upper reference limits from samples of healthy persons without established risk factors for high homocysteine concentrations have been used to define a high total homocysteine concentration [13-16].
Although the distribution of plasma concentrations of homocysteine has been reported in some populations, there is little available information describing homocysteine concentrations in the healthy Iranians [17]. In the present study, total homocysteine, folate, and vitamin B12 concentrations were measured in 1214 healthy Iranians as part of "Tehran Homocysteine Survey". This study describes the distributions of total homocysteine, folate, and vitamin B12 concentrations altogether in a sample of healthy Iranians.
Study design
The present data are part of a cross – sectional study (designed as Cardiovascular Risk Factor Survey in the Population Lab Region of Tehran University) arranged and conducted based on methodology of MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Diseases)/WHO (World Health Organization) project [1,19] by EMRC (Endocrinology and Metabolism Research Center) affiliated with Tehran University of Medical Sciences (TUMS). We recruited 1573 apparently healthy residents of 17th district of Tehran – capital city of Iran – randomly chosen by one stage cluster random sampling from a group of 255337 people. This south western district of Tehran is the most crowded one, with low income inhabitants. Because of its unique characteristics, there has been selected as Tehran University Population Lab Region.
Subjects and study criteria
Totally, 1573 healthy (without any history of severe renal, liver and cardiac dysfunction) participants (615 men and 958 women) aged 25–64 years were recruited: 140 were not interested to take part in this part of study, 152 did not meet the inclusion criteria (being healthy and 25–64 years old), and 67 had incomplete laboratory data.
Therefore, our analyses are based on 1214 participants (428 men and 786 women) with complete data on plasma total homocysteine, folate, and vitamin B12 concentrations. Exclusion criteria included known coronary heart disease (CHD), systemic illness, serious organ disease, proliferative and endocrine diseases, alcoholism, current pregnancy, current use of vitamins or other supplements, anticonvulsant and anticancer therapy. Participants underwent a standardized medical history, physical examination, anthropometric measurements and laboratory tests. Personal and lifestyle information were obtained by using modified MONICA questionnaires [18]. All respondents gave their written informed consent.
Our research protocol was approved by the EMRC ethics committee and was conformed to the principles embodied in the declaration of Helsinki.
Laboratory analyses
Fasting blood samples were obtained in the early morning hours after 12 hours fast. The plasma samples were put in a cooled container and immediately carried to the EMRC laboratory, where the plasma was separated within 2 hours of sampling by centrifugation (20 min, RT, at 2000 RPM) and aliquots were stored at -70°c until determinations. In this part of the study, the following parameters were analyzed: total plasma homocysteine, serum vitamin B12 and serum folate. Plasma total homocysteine concentrations (the sum of homocysteine and homocysteine-cysteine mixed disulfides, free and protein-bound) were determined on frozen samples by HPLC (High-performance Liquid Chromatography) method (KNAUER, Germany), coupled with fluorescence detector. The method has been validated over a linearity range of 1–100 μmol/L from plasma. The intra-assay and inter-assay coefficient of variation for homocysteine samples were 3.9% and 5.8% respectively. Folate and vitamin B12 were measured simultaneously in the frozen serum aliquot by a double labeled radioassay kit (ICN Pharmaceuticals, New York). The intra-assay coefficient of variation for folate and vitamin B12 were 6.9% and 6.1%, respectively. The inter-assay coefficient of variation for folate and vitamin B12 were 7.5% and 6.8%, respectively.
Statistical analyses
The distributions of total homocysteine, folate and vitamin B12 concentrations were skewed to the right. Therefore values were logarithmically natural transformed (Ln) to promote normality and presented as geometric mean and 95% confidence intervals. Various quartiles of homocysteine were estimated in analyses stratified according to the strongest predictors of mean total homocysteine concentrations in multivariate analysis: sex, age, folate score and vitamin B12 score. All values were calculated as mean ± SD (standard deviation) for the total group and separately by sex and age. Associations between categorical variables were reported by Chi-square test. Continuous variables were compared by Student's t test. A P value < 0.05 was considered significant. Data were analyzed by using Statistical Package for Social Sciences (SPSS) version 11.5 software.
A folate concentration less than 11 nmol/L [8,20,21] and a vitamin B12 concentration less than 185 pmol/L[8,22] served as the criterion for defining low vitamin levels. We also defined hyperhomocysteinemia (HHcy) as Table 1 demonstrates.
Table 1. Based Homocysteine Ranges in Our Study [23]
The group studied contained 428 (35.3%) male and 786 (64.7%) female 25–64-y-old individuals. Table 2 shows the clinical characteristics, nutritional state and other risk factors in the study participants.
Table 2. Clinical characteristics, risk factors and nutritional state of the study population
Proportion of individual in each homocysteine classes has been shown in table 3. Hyperhomocysteinemia (tHcy≥ 15 μmol/L) was detected in 313 (crude prevalence: 73.1%, age-adjusted: 73.1%) males and 330 (crude prevalence: 42%, age-adjusted: 41.07%) females which was significantly higher in men than women (P < 0.0001). Although crude and age-adjusted prevalence of low folote levels (<11 nmol/L) were observed respectively in 98.8% and 98.67% of males and 97.9% and 97.92% of females, the difference between sexes was not statistically significant (P = 0.281). Crude and age-adjusted prevalence of low vitamin B12 levels (<185 pmol/L) were determined respectively in 26.8% and 26.32% of male and 27.3% and 27.2% of female individuals but the difference was not statistically significant either (P = 0.846).
Table 3. Proportion of individual in each homocysteine classes according sex and age groups
Crude prevalence of Hyperhomocysteinemia for 45–54-year and 55–64-year-old age groups among both males and females were 79.1%, 87.4% and 44.6%, 57.1%, respectively (Table 4).
Table 4. Prevalence of Hyperhomocysteinemia and Low Vitamin Concentrations According to Sex and Age Group
Notably, 12% (n = 146) of participants had normal total homocysteine concentrations, but mild and moderate hyperhomocysteinemia were detected in 47.6% (n = 578) and 5.4% (n = 65) of individuals, respectively. Crude, age and sex-adjusted prevalence of hyperhomocysteinemia in total participants were 53% and 56.2%, respectively. Crude prevalence of low folate, and vitamin B12 levels were detected in 98.2% (age and sex adjusted: 98.3%) and 27.1% (age and sex-adjusted: 26.77%) of total subjects respectively.
Correlation coefficients (Pearson's r) between log tHcy and serum folate, and vitamin B12 indicated an inverse correlation (r = -0.27, r = -0.19, P < 0.0001, respectively).
The geometric mean of total homocysteine level is the highest in 55–64-year-old age group as Table 5 presents. But in this age group, men had higher homocysteine concentrations than women.
Table 5. Mean Total Homocysteine, Folate and Vitamin B12 According to Sex and Age Group
The lowest level of serum folate was considered in both male and female 45–54-year age groups. The lowest level of vitamin B12 was determined in male 45–54-year-old and female 35–44-year-old age groups. In general, geometric mean of homocysteine was higher in men than women, and increased by age, but geometric mean of serum folate in all age groups were higher in men than women. Geometric mean of serum vitamin B12 was higher in all female age groups (except 35–44-year-old) than similar male age groups. Overall geometric mean of total homocysteine, folate, and vitamin B12 levels were 15.64 ± 1.50 μmol/L, 3.94 ± 1.67 nmol/L, 262.88 ± 1.82 pmol/L, respectively.
Men had significantly higher mean plasma homocysteine concentration than women (geometric mean = 19.02 ± 1.46 μmol/L, compared with 14.05 ± 1.45 μmol/L, P = 0.004) and lower mean serum folate levels than women (geometric mean = 3.66 ± 1.65 nmol/L compared with 4.1 ± 1.67 nmol/L, P < 0.0001). Mean serum vitamin B12 was not significantly higher in women (geometric mean = 269.27 ± 1.75 pmol/L) than in men (geometric mean = 251.39 ± 1.94 pmol/L, P = 0.063).
Distribution of participants according to their total homocysteine, folate, and vitamin B12 level quartiles (Q1–Q4) are displayed in Table 6.
Table 6. Distribution of Participants in Each Sex and Age Group Based on Their tHcy, Folate and Vitamin B12 Quartiles
By increasing age, there was a decreasing frequency in first quartile of homocysteine, while in fourth of homocysteine quartile in both sexes, an increasing frequency was considered by aging.
Regarding homocysteine quartiles, the highest distribution was found in male 55–65-year-old and female 25–34-year-old age groups. According to folate quartiles, the highest distribution was seen in male 45–54-year-old and female 55–64-year-old age groups.
Thresholds of each tHcy, folate and vitamin B12 quartiles were: 12.20, 2.80 and 174.00 μmol/L; 15.00, 4.00 and 285.00 μmol/L; 20.20, 5.40 and 378.00 μmol/L, respectively.
Many studies have shown that elevated total homocysteine concentration is an independent risk factor for cardiovascular diseases [24-27]. Total plasma homocysteine levels are higher in men than in women and at older ages [25,23]. Folate and vitamin B12 are the major nutritional determinants of homocysteine levels [28]. Persons with low circulating folate or vitamin B12 concentrations have higher fasting total homocysteine concentrations [13,23]. Elevated fasting homocysteine concentrations in turn, are usually normalized by treatment with folic acid and vitamin B12 [29,30]. Although epidemiologic surveys have determined total homocysteine concentrations in order to identify the prevalence of hyperhomocysteinemia, estimation of these cases is complicated by the lack of a standard definition of a high total homocysteine concentration [8,15,16,30].
In our study, the prevalence of hyperhomocysteinemia and low folate and vitamin B12 levels were higher than other populations [2,8,16,17,31]. Prevalence of hyperhomocysteinemia and the mean homocysteine concentrations were higher in men than in women and at older ages. The age and sex differences in total plasma homocysteine levels observed in this study are consistent with observations from published studies in large and small sample size of adult men and women in some reported populations [32,33]. Plasma homocysteine concentrations are increased with age and higher in men than in women [25,31,34,35].
For every 20 years of age, Hcy increases on average by 1.3 μmol/L [36]. The reasons for higher homocysteine concentrations at older ages are not well understood, although changes in renal function and impaired renal metabolism of homocysteine may be involved [37,38]. Furthermore, elevated plasma homocysteine concentrations in older populations can also be attributed to low blood folate concentrations [39] and an increased incidence of vitamin B12 deficiency resulting from malabsorption of vitamin B12 by the aging gut [40]. Men have average 1 μmol/L higher Hcy values than women [34,36]. Higher homocysteine concentrations in males than in females could be due to larger muscle mass and greater creatine phosphate synthesis in men, [1] lowering effect of estrogens in women [41] and differences in vitamin status [25] and homocysteine formation between sexes [1]. Part of the relationship with age in women might be explained by menopause, since the homocysteine concentration was found to be higher in post-menopausal women compared with premenopausal women [34].
In present study, mean total homocysteine concentration is notably higher than what other surveys have reported [2,8,16,17,31]. In addition, we observed that the prevalence of mild hyperhomocysteinemia (15< Hcy <30 μmol/L) was 47.6%. Probably, the condition of homocysteine distribution and concentration of values around ranges 10–30 μmol/L and low prevalence of normal total homocysteine concentrations in this sample, caused increase in the mean homocysteine level. In other words, although the mean homocysteine level is high, the severity of hyperhomocysteinemia is not that much. Furthermore, serum folates, and vitamin B12 levels compared to values from various countries, indicate that prevalence of low levels of folate, and vitamin B12 is higher in our sample [2,8,16,17,31]. It could be due to geographical variations, racial and ethnic differences [17], genetic causes, different lifestyle, and inadequate intake of B vitamins and folate, inaccurate cooking of vegetables and not implementing fortification of grain products with folic acid in our country. As it has been shown in table 1 it seems that low daily intake of vitamin B12 and folic acid is the eventual cause of low folate levels in our study population. Prolonged cooking of vegetables may destroy up to 90% of folate content [42]. Candidate genes can regulate plasma homocysteine concentrations, especially methylene tetrahydrofolate reductase (MTHFR) and cystathionine-β-synthase (CBS) genes. Recent studies have shown the importance of DNA polymorphisms in the genes for enzymes involved in homocysteine metabolism [31]. Moreover, it has been reported that rural-to-urban migrant population living in urban slums undergoing stressful socio-economic transition are likely to have low intakes of folate, and vitamin B12, which may have an adverse impact on plasma levels of homocysteine [43].
Limitations of the present investigation include not assessed several factors that might be associated to elevated tHcy, such as creatinine and vitamin B6 concentrations.
Our results confirm the findings of other observations that elevated total homocysteine concentrations are potentially attributable to low vitamin levels. Because folate is an established predictor of homocysteine concentration, it would be useful to investigate the effect of folate enrichment of foods on homocysteine concentration in the current Iranian population. Although firm therapeutic guidelines are lacking, consideration should be given to treatment as a primary prevention measure for patients whose baseline homocysteine level exceeds 15 μmol/L. Folic acid supplementation in a dose of 400–800 mg/day effectively lowers plasma homocysteine levels in a significant percentage of individuals, with the higher dose being needed by many to achieve a meaningful reduction in plasma homocysteine. However some patients will not respond to this dose of folate. This makes close follow-up and periodic monitoring of homocysteine levels essential. The only way to truly know if folate treatment is being effective is to recheck the homocysteine level [44]. This guideline could be followed by family physicians. Another essential prevention guideline is planning for fortification of enriched grain products with folic acid in Iran like many other countries [45]. The main motivation behind fortification is to abate the occurrence of neural tube defects (NTDs), a birth defect shown to be responsive to folic acid administration [46]. A secondary benefit of fortification might be a reduction in the incidence of cardiovascular disease [47] and probably certain cancers, [48] the occurrence of which are associated with low folate status. The success of fortification was quickly seen [45] with the declining incidence of folate deficiency and a concurrent decrease in the incidence of elevated plasma total homocysteine [49].
Although the distribution of plasma concentrations of homocysteine, folate, and vitamin B12 has been reported in some populations of other countries, there is little or no available information describing these parameters in healthy Iranians and their relations to gender and age. There is only one study that has reported homocysteine levels in Iranians. In this study, 402 participants 15 years of age or older of southwest of Iran were monitored and the mean plasma homocysteine level was reported significantly higher in men than women [17].
The cost effectiveness of assessment of homocysteine as a cardiovascular risk factor is important. The cost for homocysteine measurement is higher than other risk factors at individual level. However, since it has been reported as a highly potential risk factor of CHD [1,4,11] which can be modified easily by food supplementation with folate and vitamin B12, its assessment is valuable and has cost benefit at the public health level.
In conclusion, we found the association between plasma homocysteine concentration and age and sex, and blood levels of vitamins by using data from a cross-sectional study based on MONICA/WHO similar to other studies worldwide. Also, we reported that plasma homocysteine concentration was inversely associated with folate and vitamin B12 levels. The variables sex and age were not independently associated with homocysteine levels when other variables were considered. Because this study used cross-sectional data, it was not possible to evaluate the data in terms of cause-and-effect relations.
So far, little has been published on distribution of total homocysteine concentrations in healthy Iranians. This study describes the distributions of total homocysteine, folate, and vitamin B12 concentrations altogether in a sample of healthy Iranians. According to significance of genetic and ethnic factors on total homocysteine level, we are conducting a study to observe Iranians' MTHFR (methylene tetrahydrofolate reductase) and CBS (cystathionine-β-synthase) polymorphisms. In addition, our clinical trials are underway to investigate the impact of folic acid supplements on plasma homocysteine concentrations and hypertension in Iranian population. Since there are little or no available information in our country, it is possible that future studies could reveal excess determinants of hyperhomocysteinemia.
List of abbreviations
CBS: cystathionine-β-synthase, CHD: coronary heart disease, EMRC: Endocrinology and Metabolism Research Center, Hcy: homocysteine, HHcy: hyperhomocysteinemia, HPLC: High-performance Liquid Chromatography, MONICA: Multinational Monitoring of Trends and Determinants in Cardiovascular Diseases, MTHFR: methylene tetrahydrofolate reductase, NTDs: neural tube defects, tHcy: plasma total homocysteine, RPM: round per minute, RT: room temperature, TUMS: Tehran University of Medical Sciences, WHO: World Health Organization.
Competing interests
The author(s) declare that they have no competing interests.
Authors' contributions
1) HF: principle investigator, has made substantial contributions to conception and design of the study
2) SG; has made substantial contributions to data acquisition and has been involved in drafting and interpretation of data
3) RP: co-principle investigator has made substantial contributions to data acquisition
4) MN has made substantial contributions to data acquisition
5) RH has made substantial contributions to analysis, interpretation and revising of data
6) AS; has made substantial contributions to data acquisition
7) FB: critical revision, data analysis and substantial contribution
8) BL; has given final approval of the version to be published
This National Health Survey was financially supported by grants from the "Management and Planning Organization" of Iran. The authors are indebted to Mr. Peyman Shooshtarizadeh for his skilled technical help. Authors also express their appreciation to "EMRC" laboratory staff, "Iran Statistics Centre" and "Statistics, Social Sciences, Nursing and Laboratory Teams" of the survey. We also thank the people of 17th district of Tehran who took part in the study.
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Pre-publication history
The pre-publication history for this paper can be accessed here:


text:
A cantilever stylus with an integrally formed conical tip is provided for atomic force microscopy AFM. The method for forming a stylus includes forming a circular masking pattern on the surface of a silicon substrate and anisotropically etching the silicon to form a post under the masking pattern. The post is then isotropically etched to produce a conical silicon tip mold. In one embodiment of the invention the silicon substrate and the conical silicon tip mold are thermally oxidized to form a cantilever stylus having including a cantilever arm with a conical tip fixed to its free end. In another embodiment of the invention the silicon substrate and the conical silicon tip mold are coated with a thin film of a dielectric material to form a cantilever stylus with a conical tip. In this embodiment the backside of the stylus is coated with a conductive material and a strong electric field is applied to the tip to cause electromigration of the conductive material to the point of the tip.
1. A method of forming a silicon tip, comprising the steps of:
forming a masking layer having a predetermined masking pattern on a portion of the surface of a silicon substrate;
anisotropically etching said silicon substrate to form a silicon post on said silicon substrate beneath said masking pattern; and
isotropically etching said silicon post to form a pointed silicon tip.
2. A method of forming a cantilever stylus with an integral pointed tip, comprising the steps of:
forming a masking layer having a predetermined masking pattern on a portion of the surface of a silicon substrate;
anisotropically etching said silicon substrate to form a silicon post on said silicon substrate beneath said masking pattern;
isotropically etching said silicon post to form a pointed silicon tip on said silicon substrate;
forming a cantilever stylus which includes a cantilever arm and said pointed silicon tip fixed thereto;
selectively removing selected portions of the silicon substrate to release said cantilever stylus from said silicon substrate.
3. The method of claim 1 wherein the step of forming the cantilever stylus includes the steps of:
thermally oxidizing said pointed silicon tip and a patterned portion of said silicon substrate to form a silicon dioxide cantilever stylus.
4. The method of claim 1 wherein the step of forming the cantilever stylus includes the step of depositing a thin film material over said pointed silicon tip and patterned portions of said silicon substrate to form a cantilever stylus of said thin film material.
5. The method of claim 4 wherein the step of depositing a thin film over said pointed silicon tip and portions of said silicon substrate to form a cantilever stylus includes using a thin film material selected from the group consisting of silicon nitride, deposited silicon dioxide, aluminum, aluminum oxide, gold, and polysilicon.
6. The method of claim 1 wherein the step of forming the cantilever stylus includes the step of:
forming a thin film of a first material over said pointed silicon tip and adjacent areas of said silicon substrate to thereby provide a stylus tip;
forming a thin film of a second material over portions of said silicon substrate and areas of said silicon substrate adjacent to said stylus tip to form a cantilever arm of said second material with said stylus tip fixed thereto.
7. The method of claim 6 wherein said first material is thermally grown SiO2 and said second material is Si3 N4.
8. The method of claim 1 wherein the step of forming a masking pattern on the silicon substrate includes the steps of:
depositing a masking layer on the silicon substrate;
forming a pattern of photoresist material on said masking layer;
removing portions of said masking layer to leave said masking pattern on said silicon substrate.
9. The method of claim wherein said masking pattern is circular and approximately 1 micrometer in diameter.
10. The method of claim 1 wherein the step of anisotropically etching the silicon substrate is done by dry etching.
11. The method of claim 1 wherein the step of anisotropically etching includes etching the silicon substrate to a predetermined depth.
12. The method of claim 1 including the step of etching away said silicon post until the masking layer is detached from the silicon substrate.
13. The method of claim 1 wherein the step of isotropically etching the silicon post includes the step of controlling the slope of the sidewall of the conical tip by varying the ratio between the depth of anisotropic etching for the silicon post and the amount of isotropic etching used to etch the silicon post into a pointed silicon tip, and by controlling the anisotrophy of the etching.
14. The method of claim 1 wherein the step of isotropically etching the silicon post includes etching said post with a reactive ion plasma.
15. The method of claim 1 wherein the step of isotropically etching the silicon post includes etching said post by ion milling.
16. The method of claim 1 wherein said masking layer is selected from the group consisting of thermally grown silicon dioxide, silicon nitride, deposited silicon dioxide, aluminum, or photoresist material.
17. The method of claim 1 wherein the step of anisotropically etching the silicon substrate to form a silicon post includes using an etchant selected from the group consisting of SF6/C2ClF5, CF4, and SF6 plasma.
18. The method of claim 1 including the steps of:
forming the stylus tip to have a thickness which is less than its height and diameter;
coating the backside of the stylus tip with a conductive material to form a conductive layer;
applying a voltage between the conductive layer and an electrode spaced apart from the point of said stylus tip to cause electromigration of said conductive material through said dielectric material to the point of said stylus tip to provide a conductive stylus tip.
19. The method of claim 1 including forming a plurality of cantilever styluses with integral tips on various portions of the surface of said silicon substrate.
20. The method of claim 1 wherein the masking pattern is shaped in a substantially circular pattern to form a substantially cylindrical silicon post which results in a substantially conical pointed tip.
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. N00014-84-K-0237 awarded by the Department of the NAVY.
1. Field of the Invention.
This invention relates to microminiature tips and, more particularly, to microminiature tips formed using semiconductor integrated circuit fabrication techniques.
2. Prior Art.
An atomic force microscope (AFM) scans over the surface of a sample in two different modes of operation. In one mode, the contacting mode, a sharp tip is mounted on the end of a cantilever and the tip rides on the surface of a sample with an extremely light tracking force, on the order of 10-5 to 10-10 N. In the contacting mode of operation, profiles of the surface topology are obtained with extremely high resolution. Images showing the position of individual atoms are routinely obtained. In the other mode, the tip is held a short distance, on the order of 5 to 500 Angstroms, from the surface of a sample and is deflected by various forces between the sample and the tip, such forces include electrostatic, magnetic, and van der Waals forces.
Several methods of detecting the deflection of the cantilever are available with subangstrom sensitivity, including vacuum tunneling, optical interferometry, optical beam deflection, and capacitive techniques. However, fabrication of a readily reproducible cantilever stylus assembly has been a limiting factor on use of AFM and other forms of microscopy such as scanning tunneling microscopy.
The technical requirements for the cantilever-and-tip assembly include a number of different factors. A low force constant for the cantilever is desirable so that reasonable values of deflection are obtained with relatively small deflection forces. Typical values are 0.01-1000 N/m. A mechanical resonant frequency for the cantilever which is greater than 10 kHz is desirable to increase image tracking speed and to reduce sensitivity to ambient vibrations. Low force constants and high resonant frequencies are obtained by minimizing the mass of the cantilever.
When optical beam deflection is used to detect deflection of the cantilever, deflection sensitivity is inversely proportional to the length of the cantilever. Therefore a cantilever length of less than 1 mm. is desirable.
For certain types of deflection sensing, a high mechanical Q is desirable and is achieved by using amorphous or single crystal thin films for fabrication of the cantilever.
In many applications, it is desirable that the cantilever flex in only one direction and have high lateral stiffness. This can be obtained by using a geometry such as a V-shape which has two arms obliquely extending and meeting at a point at which the tip is mounted.
It is often required that a conductive electrode or reflective spot be located on the side of the cantilever opposite the tip. This is obtained by fabricating the cantilever from metal or depositing a conductor on certain portions of the cantilever to serve as a conductor or reflector.
Finally, a sharp tip, that is, a protruding tip with a tip radius less than 500 Angstroms and which may terminate in a single atom, is desired to provide good lateral resolution. The sharper the tip, the higher the resolution, especially when operating in the contact mode. This requirement has traditionally been one of the most difficult to obtain in a reproducible manner. Typically, in the prior art, tips were fabricated by hand using fabrication and bonding techniques which were time consuming and which produced non-uniformly performing tips.
In the prior art, cantilever arms were constructed by hand from fine wires. One way of obtaining a tip portion was to etch a wire to a point and to bend the point to extend perpendicularly from the wire. Another way to obtain a tip was to glue a tiny diamond fragment in place at the end of a cantilever. Prior art cantilevers fabricated using photolithographic techniques did not have integrally-formed sharp protruding tips. A rather dull tip was effectively obtained by using a corner of the microfabricated cantilever itself as a tip. Alternatively, a diamond fragment was glued by hand to the end of a microfabricated cantilever. The cantilever assembly of an AFM is relatively fragile and is virtually impossible to clean when it is contaminated by material from the surface being scanned so that frequent replacement is required.
Background information on well known prior art fabrication methods used in this invention can be found in the following references: Information on wet anisotropic Si etching and macromachining in general is described by K. E. Petersen, Proc. IEEE 70, 420 (1982). Isotropic and anisotropic dry plasma etching of Si and other materials is discussed in the book "Silicon Processing for the VLSI Era" by Wolf and Tauber. Inert ion etching, including ion milling, and many other aspects of microfabrication are discussed in the book "The Physics of Microfabrication" by Brodie and Muray. The electromigration phenomena exploited in the construction of dielectric tips with conducting metallic points is discussed in the book "VLSI Fabrication Principles" by Ghandhi. Information on the need for insulated STM tips is discussed by M. M. Dovek et al. in "Molecular Phenomena at Electrode Surfaces," ACS Symposia Series, edited by M. P. Soriga (in press).
Extremely high resolution profiles of surface topography can be obtained in the contacting mode of operation; in fact, images showing the positions of individual surface atoms are routinely obtained with the AFM. Therefore, a reproducible method for fabricating tips is a significant contribution to AFM technology.
It is therefore an object of the invention to provide a cantilever assembly having a microminiature tip fixed to the free end thereof for application in scanning tunnelling microscopy, atomic force microscopy, and in other applications requiring a microminiature sharp tip which is uniform, sharp, well-formed, durable, and inexpensive.
It is another object of the invention to provide a microminiature tip which is fabricated using semiconductor integrated circuit fabrication processes.
It is another object of the invention to provide a cantilever assembly for an AFM which is fabricated using microfabrication techniques.
In accordance with these and other objects of the invention, a cantilever stylus having an integrally-formed conical tip and a method for producing a cantilever stylus with an integral conical tip are provided according to the invention.
In accordance with these and other objects of the invention, a cantilever arm stylus with an integrally formed conical stylus is provided. The tip is formed by anisotropic dry etching of Si to form a Si post and subsequent sharpening of the post to a sharp tip by isotropic dry etching. This Si tip is incorporated into a thermally grown SiO2 layer from which the cantilever is made. Part of the Si substrate is removed to free up the cantilever. Alternatively, the cantilever and tip may be formed of other materials, such as Si3 N4, Al2 O3, deposited SiO2, Au, silicon, or polysilicon. The cantilever may also be made from a different material than the tip. One variation is also described which produces tips with conducting metallic point surrounded by dielectric material.
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention:
FIGS. 1 through 5 are cross-sectional views showing the results of various process steps for forming a sharp conical tip on the surface of a silicon wafer.
FIG. 6A is a cross-sectional view showing a thermally-grown SiO2 film patterned on a silicon wafer to form a V-shaped cantilever stylus with an integral conical tip.
FIG. 6B is a plan view of the stylus and integral tip of FIG. 6A.
FIG. 7 is a cross-sectional view of a finished cantilever stylus assembly.
FIGS. 8 through 10 are cross-sectional views showing the results of an embodiment of the invention in which the cantilever arm and the integral conical tip are formed of materials deposited on a silicon substrate and a conical silicon tip mold.
FIGS. 11 through 13 are cross-sectional views showing the results of an alternative embodiment of the invention in which the cantilever arm is made from a different material than the tip.
FIG. 14 shows a variation of the invention in which electromigration is used to draw a narrow filament of metal through a dielectric conical tip to produce a conducting point surrounded by insulating material.
Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to those embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims.
FIG. 1 shows the first step in a process, which starts with a silicon wafer, or substrate, 10. Deposited on the surface 12 of the silicon wafer 10 is a thin film 14 of suitable masking material. An example of such a masking film layer 14 is a 1000 Å film of thermally grown SiO2.
FIG. 2 shows photoresist patterned into a small, preferably circular shaped, spot 16 several microns in diameter formed on the surface of the masking layer 14. The masking layer 14 is shown etched away except for the remaining area under the photoresist spot 16. The size of the spot determines the approximate diameter of the base of a substantially conical tip which is to be formed. Note that the photoresist spot and the remainder of the masking layer 14 do no need to be perfectly circular. A photoresist pattern which deviates from a circular pattern, such as a square or a somewhat oblong pattern is acceptable to produce a cantilever tip having a generally conical shape.
FIG. 3 shows the formation of a Si post 18 on the remaining surface of the wafer 10 formed by etching away several microns of Si 20 from the wafer's original surface 12. An anisotropic dry etch is used to obtain steep sidewalls on the post 18. The photoresist spot 16 and the remainder of the masking layer 14 improve the anisotropy of this etch. The depth of this etch should exceed the desired height of the conical tip which is to be formed.
FIG. 4 shows the sharpening of the post 18 into a conical tip 20. First the photoresist spot 16 is removed, followed by isotropic dry etching of the top layer 22 of the silicon substrate until the remainder of the masking layer 14 detaches from what is left of the post 18. This forms a substantially conical tip mold 20. The slope of the sidewalls of the tip 18 can be adjusted by varying the ratio of the depth of the anisotropic etch used to form the post 18 and the amount of isotropic etching used to sharpen the post into the tip mold 20. This completes formation of the silicon tip mold 20.
Note that the silicon post 18 can have a shape which deviates from cylindrical, depending on the pattern of the masking layer 14. The shape of the post 18 is intended to include a variety of shapes.
FIG. 5 shows an SiO2 layer, or film, 24 formed by growing an oxide out of the Si on the surface of the wafer, including the tip mold portion 20 shown in FIG. 4. The SiO2 is formed from the Si by thermal oxidation, which preserves the approximate shape of the original Si surface and tip mold 20. Thus, the sharp Si tip mold 20 serves to form an equally sharp SiO2 tip 26. SiO2 also forms on the bottom side of the substrate 10.
FIGS. 6A and 6B (in a plan view) show how the SiO2 film 24 is formed into a cantilever. The top SiO2 film 24 is patterned photolithographically into the shape of a cantilever 30. The cantilever 30 is V-shaped in the drawing, but may be of any suitable shape, such as rectangular. The cantilever 30 is patterned so that a tip 42 is located at the end of the cantilever. The bottom SiO2 film 50 is patterned as shown so that an anisotropic etch of the Si wafer 10 in a subsequent step can self-terminate and retain part of the wafer 10 at the base of the cantilever 30. This requirement is met by patterning the edge of the bottom SiO2 film 50 to lie in a Si (111) plane 52 which also intersects the base of the cantilever 40.
FIG. 7 shows a finished cantilever stylus assembly, consisting of a sharp conical tip 42 located at the free end of a SiO2 cantilever 30 which is attached at its base to a retained part of the Si wafer 10. An anisotropic Si etch is used to remove the part of the wafer 10 located under the cantilever 30. This etch self-terminates at the (111) plane 52 in the Si. The bottom side of the cantilever 30 and the retained part of the wafer 10 are coated with a conductive metal coating 60 for detecting displacement in an AFM.
Since each cantilever stylus structure is quite small (typical size 100�100 microns), hundreds of cantilevers can be constructed simultaneously on a single Si wafer, taking advantage of the excellent reproducibility and the low unit cost available from batch-processing fabrication techniques.
A number of variations are possible in the fabrication process. For example, the initial masking SiO2 film 14 can be replaced with any material suitable as a mask for the anisotropic dry etch used to form the Si post 18. Si3 N4, deposited SiO2, and Al are suitable examples. The thickness of the masking film is not very important. There are a variety of dry etchants which can be used to form steep sidewalls in Si. One example is SF6 /C2 ClF5 plasma with photoresist present.
The Si post 18 is alternatively sharpened into a sharp tip mold 26 by inert ion milling instead of using a reactive ion plasma etch. Ion milling is known to sharpen and accentuate any surface protrusions and sharpen the post 18 into a conical tip as desired.
FIGS. 8,9,10 show an alternative embodiment of the invention in which the cantilever and its tip are formed of deposited material rather than of thermally grown oxide. much as possible, the final tip 42 is formed by thermal oxidation of the Si tip mold 20. However, the final tip 42 and cantilever 30 can be made of other suitable deposited thin film materials, including, for example, Si3 N4, deposited SiO2, Al2 O3, Al, or Au. When deposited films are used, the Si tip mold 20 serves as a form around which a deposited film is cast into the approximate shape of the tip mold 26 to provide a cantilever tip 42 which is integrally formed with a cantilever arm 74. The Si tip mold 26 is later removed along with the rest of the Si substrate under the cantilever. This method differs from the oxidation method where the Si tip mold material is transformed directly into the SiO2 tip. Si3 N4 is a particularly good material, since its high strength and low internal stress yield very robust and durable cantilevers.
FIGS. 11 through 13 show another embodiment which preserves the sharpness of the SiO2 tip mold in a scanning tip which has the durability of a cantilever arm made of another material, such as Si3 N4. This embodiment starts with the structure as shown in FIG. 5. All of the SiO2 layer 24 is removed except a small region around and including the tip 42. Then the entire surface of the wafer 10 including the tip 42 is coated with a layer 80 of Si3 N4 as is shown in FIG. 11. FIG. 12 shows the next step, which is the removal of the Si3 N4 film 80 from over the tip 42 leaving a small overlap at the boundary to improve adhesion of the tip 42 to the film 80. The cantilever stylus assembly with a cantilever arm 82 is completed as described previously, except that the Si3 N4 film 80 takes the place of the SiO2 film 24 in the remaining steps. The SiO2 tip 42 remains intact in the finished product, which is shown in FIG. 13.
In any of the variations described above, the size and shape of the cantilever, and the size and aspect ratio of the tip can be varied over a large range.
One of the embodiments of the invention details the construction of dielectric tips with conducting metallic points. The point of the conical tip structure is conductive, but the rest of the tip structure is insulating. A connection is provided by electromigration of conductive material through the end of the tip so that an electrical current can flow through to the point. This structure is a microfabricated version of the type of tips used in scanning tunneling microscopy (STM) operated in electrolytes, where the ion current would be too large if the entire tip structure were metallic. Insulating everything except the very point reduces the ionic current so that the tunneling current from the point of the structure can be easily detected and controlled. Previous fabrication methods for this type of tip involve coating tips formed from wires with glass or polymer coatings on a one-at-a-time basis.
This variation of the invention is shown in FIG. 14. In this case, a cantilever 90 and a tip 92 are made of a thin dielectric layer by either the thermal growth of SiO2 or deposition of any dielectric material as described hereinabove. The dielectric film should be thin enough so that its thickness is much less than the height or diameter of the tip. As in the previous first embodiments, the back of the cantilever and tip is coated with a metal layer 60. Electromigration is used to draw a narrow filament of metal 80 through the dielectric film at the point of the conical tip. This is accomplished in a simple manner by applying a high voltage (several kV) between the metal film 60 and a planar electrode located above the tip up to several cm away. Raising the temperature of the tip speeds up the process. The electric field is greatly enhanced by the sharpness of the metal cone formed under the dielectric cone, and this field causes electromigration of metal along a path 94 through the dielectric to the surface of the dielectric at the point. This forms a conducting tip surrounded by insulating material suitable for use in the STM for electrochemistry applications.
This new method offers significant advantages because the shape of the tip is highly symmetric and its height and aspect ratio can be controlled.
The fabrication process presented here is a batch fabrication process which permits the construction of a sharp conical tip as an integral part of the entire cantilever fabrication process. Since this process is capable of producing hundreds of identical structures simultaneously on a silicon wafer, cantilever arms having conical tips are easily reproduced in large quantities.
The concept of microfabricating thin-film cantilevers itself is not new. Nor is their application in an AFM new. (although this occurred in our lab first). What is new is the method of fabricating a sharp conical tip and the inclusion of the conical tip as an integral part of the cantilever fabrication process.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.
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'Pininyahang manok'
One of the richest provinces in the Southern Luzon region, Batangas is known for its cattle ranches, its pineapple and coconut plantations, and vast hectares of sugar plantations. Because it's along the coastline, it has access not only to beautiful beaches but also to the harvests of the sea.
As a result, Batangas' cuisine is rich and varied. Among the dishes it's known for is beef bulalo, a hearty soup of beef shanks and beef bone marrow patiently simmered to tenderness. Maliputo, found in the waters of Taal Lake, is a highly prized fish because of its delicate flavor. And with sugar being a major product, specialties of the province include delicacies such as suman made with panotsa.
These and other Batangas dishes will be part of the lunch and dinner buffet of Hotel InterContinental's Café Jeepney until September 30. The crabs cooked in coconut milk is a must-try. For this dish, Hotel InterCon uses the special crabs found in the brackish waters of the river in Nasugbu. Because the river is near the sea, its water is salty, giving the crabs a salty-sweet flavor, according to Batangueño chefs Tats Azarcon Jr. and Randy Capule, who are assisting the Intercon chefs in preparing the buffet.
Here's the chefs' recipe for a dish that makes good use of Batangas' abundant coconut and pineapple harvests: pininyahang manok, or chicken with pineapple.
Simmered in thick coconut milk that comes from the first pressing of coconut meat, the chicken is enhanced by the flavor of sweet, fresh chunks of pineapple. This dish is best served as soon as it's cooked.
(The cuisine of Batangas will be part of Café Jeepney's lunch and dinner buffet until Sept. 30. For reservations, call tel. 7937000.)
Pininyahang Manok
- 1 ½ kg chicken
- 2 tbsp cooking oil
- onion, chopped
- 4 cloves garlic, chopped
- carrot, sliced into rounds or wedges
- potatoes, cut into cubes or wedges (see tips)
- whole fresh pineapple, peeled and cut into chunks (see tips)
- Salt and pepper, to taste
- c thick coconut milk (kakang gata)
- c chicken stock or water (only if needed)
- red bell pepper, sliced into thick strips
- green bell pepper, sliced into thick strips
1. Slice the chicken into serving pieces. In a large, deep casserole, heat the cooking oil to medium, then sauté the onions and garlic. Add the chicken and cook, stirring occasionally so the chicken browns lightly on all sides, about five to 10 minutes. Add the carrots, potatoes and pineapples. Season with the salt and pepper.
2. Pour in the coconut milk. Turn up heat. When the liquid boils, lower the heat to a simmer. Let simmer until the chicken is fully cooked and the vegetables are tender, about 15 minutes.
3. If the liquid seems too thick, add the chicken stock or water as needed. Stir in the bell peppers. Simmer for two to three more minutes. Adjust seasonings to taste. Serve with rice.
Thick coconut milk or kakang gata is the liquid from the first pressing or first squeezing of coconut meat. You can use freshly squeezed coconut milk or the canned variety. Usually, cans of thick coconut milk are labeled coconut cream.
When cooked, the potatoes and the pineapples look similar because of their yellowish color. So diners will know which one is which, cut them into dissimilar pieces. For example, you can cut the potatoes into scalloped wedges and the pineapple into triangular chunks.
When adding water or chicken stock to the simmering chicken, stir it well into the mixture so the liquids blend evenly. Add only as little as possible so as not to dilute the coconut milk.
Instead of a whole chicken that's cut up, you can use slices of your favorite parts, e.g., chicken legs, wings or thighs, etc.
For more tips, recipes and stories, visit author's blog www.normachikiamco.com, and Facebook fan page www.facebook.com/normachikiamco. Follow on Twitter @NormaChikiamco.
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text:
Main Street's Jolly Holiday, Three Kings Day, Bye-bye Bobsleds, Pier changes +MORE!
by, 01-08-2012 at 11:29 PM
Big changes are underway at the Disneyland Resort as the holiday season comes to a close. A large section of Main Street dining and retail locations have closed for major remodeling projects as the new Jolly Holiday Bakery Cafe opens at the end of the street. Meanwhile, the new bakery-cafe is serving up a selection of new and old favorites in a gorgeous new foodservice location. Across the Central Plaza, the Matterhorn Bobsleds have closed for a major refurbishment that will include the addition of a brand new fleet of bobsleds. In Fronteirland, Disney closed out the holiday season with its first-ever Three Kings Day celebration, blending festive decor with Latino culture and entertainment. Over at Disney California Adventure, construction pressed on at the major Buena Vista Street and Cars Land projects while new work got underway on remodeling the garish Midway Shops facades on Paradise Pier. Outside the parks, work has begun on some Downtown Disney projects and completing the Disneyland Hotel renovation.
We're happy to announce that you can now click on photos in Dateline Disneyland to view a higher-resoultion version of the image. Because of this new feature, you will no longer be able to click on photos featuring Project Tracker watermarks to be redirected to those threads on our MiceChat discussion boards. For your convenience, we've added handy Project Tracker banners at each relevant section of the update, so if you'd like to learn more about any project in today's update or join the on-going discussion on the MiceChat forums, all you need to do is click on through!
We've got a lot to cover this week, so let's get started!
Inside Dateline Disneyland
- Welcome to Disneyland!
Bye-bye holidays, Touring Plans crowd forecast
- Main Street goes on Holiday
Several Main Street shops close for changes as the new Jolly Holiday Bakery Cafe opens its doors
- Kings of Frontierland
Disneyland celebrates Three Kings Day with food, music and fun
- Bye-bye Bobsleds
Matterhorn Bobsleds close for an extended refurbishment
- California Construction
A look at the on-going construction at Disney California Adventure...
- Downtown Disney changes
La Brea Bakery expands, Cupcake Store gets a new location, Compass Books gets ready to close
- Disneyland Hotel Remodel
Disneyland Hotel's main entrance gets some finishing touches
- This and That
Bus zone repaving, Memories no more
- Weekly News and Information Round-Up
Weekly theme park hours, closures and refurbishments
Sponsored by TouringPlans.com | Do More. Wait Less.
and Howard Johnson Plaza Hotel Anaheim Resort.
The weekend marked the final days of Disneyland's long holiday season.
As we enter the winter off-season, our friends at Touring Plans give us a look at this week's expected crowd levels.
Although crowds will spike over the weekend, the next few weeks should be relatively quiet at Disneyland. TouringPlans.com can help you navigate the parks with our per-park Crowd Calendar, Lines - Mobile Wait Times App that gives access to current and estimated wait times for attractions, and Touring Plans detailing the best plan of attack for hitting the attractions. It's always a good time to subscribe to TouringPlans.com to plan your strategy to avoid the crowds!
Below are the predicted resort-wide crowd numbers for select days generated by the TouringPlans professional statisticians as measured for the upcoming week. For the access to the full year and per-park crowd level predictions, visit our Crowd Calendar.
Fred Hazelton Statistician, TouringPlans.com
Crowd Calendar Prediction
Crowd Tips Mon., Jan. 9 3/10 Here are some quick-hit notes that we hope you'll find helpful as you prepare your visits for the week:
- Partial block outs all weekend.
- Tuesday through Thursday Disneyland will be a 1.1.
- The MLK Day Holiday should make this weekend slightly busier than normal for a January weekend.
Tue., Jan. 10 2/10 Wed., Jan. 11 2/10 Thu., Jan. 12 1/10 Crowd levels are based on a scale from 1 to 10, with 1 being the least crowded conditions and 10 being most crowded. See Disneyland crowds for the next 365 days.
Get Disneyland wait times on your iPhone, Android, or Smartphone.
Do more. Wait less.
A last look at Town Square's Christmas tree.
Construction walls went up Thursday around the north-western quarter of Main Street as the last of the peak-level holiday crowds left Disneyland.
The OC Register's Around Disney blog had more information on the closures:
Disneyland restaurants close; new one opens
Disneyland restaurants along Main Street, U.S.A. will begin a transformation starting Thursday.
Some food venues on the west side of Main Street, U.S.A. are set to close temporarily for renovations.
Also Thursday, the new Jolly Holiday Bakery is set to have a soft opening, said John McClintock, a Disneyland Resort spokesman. The official opening is set for Saturday. The Mary Poppins-themed bakery is going in the former Plaza Pavilion, which was recently used as a center for annual pass holders.
Thursdays closures include the Carnation Cafe, Blue Ribbon Bakery and Refreshment Corner.
Crews plan to expand the now-outdoor cafe and add seating inside the building where the Blue Ribbon Bakery ran. The cafe last had indoor seating in the 1990s, according to the Disney Parks blog. The renovated cafe with an updated menu is expected to open this summer.
Other venues slated for makeovers are Gibson Girl Ice Cream Parlor and the Candy Palace. Read a story in the Disney Parks blog about the planned Main Street U.S.A. changes.
Oscar Martinez, the longest-tenured Disneyland employee who serves as a Carnation Cafe ambassador, is planning to temporarily work in the Jolly Holiday Bakery until the cafe reopens. [ LINK ]
From Carnation Cafe on Center Street to Refreshment Corner at the top of Main Street, the entire north-western quadrant of the street is closed as major changes come to the area's dining and shopping locations.
Walls wrap around the Carnation Cafe's outdoor dining patio.
The Blue Ribbon Bakery is permanently closed now. The existing Carnation Cafe was the only remaining portion of Main Street's former Carnation Ice Cream Parlor after the Blue Ribbon Bakery moved into the interior portion of the Carnation location in 1997. With the new Jolly Holiday Bakery Cafe open, the Blue Ribbon Bakery will once again become indoor dining space for the Carnation Cafe.
The current Gibson Girl Ice Cream Parlor is now closed for a remodel that is expected to address problematic crowd-flow issues in space.
The Penny Arcade is also closed...
...as well as its neighbor, the Candy Palace, which will receive a remodel and a new, expanded on-stage candy kitchen.
Next door, the Coca Cola Refreshment Corner is closed as well.
Steps away from the Refreshment Corner, on the edge of the Central Plaza, the Jolly Holiday Bakery Cafe in the former Plaza Pavilion is now open.
The location is a long-overdue return of foodservice to the building, which sat unused at times and was most recently used for Annual Passport processing. The new Mary Poppins theme may come at the cost of more out-of-place characters encroaching on turn-of-the-century Main Street, U.S.A. but the reward of having an operating dining location open for guests outweighs the thematic misstep.
Windows on the front of the building continue the penguin motif established on the restaurant signage. The stained glass is very nicely done, but the penguins (four in total) may call more attention than necessary.
Inside, queue space is tight so extended queue extends onto the building's front porch.
New lighting fixtures
Once inside, the queue splits in two. Each side passes by a nice tribute to the cooking-themed mural that once graced the back wall of the restaurant when it was a open as a Stouffer's-sponsored location.
The original mural was saved behind a faux wall when the restaurant was converted into the Annual Passport processing center, intended to be removed and preserved at a later date. Unfortunately, it was destroyed during recent construction. Disney artist Kevin Kidney discussed the issue at length on his personal blog, which you can read here (highly recommended). The new mural tributes feature numerous Mary Poppins references in addition to song lyrics from the film. A nice tribute, despite the needless Poppins references..
Display cases in the queue, which cleverly double as condiment bars, feature Mary Poppins-related figurines.
Gorgeous new lighting fixtures
The queue switchbacks are divided with wrought-iron railing. A nice touch.
Silhouettes on the wall of Mary and the Banks children.
The queue ends at a tile mosaic of Bert's chalk drawing from the film
The bakery's move down Main Street included the addition of a new cafe menu in addition to the coffee and espresso beverages and baked goods.
All of the food items from the sandwiches to the pastries are pre-made and are on display in large display cases found at the end of the queue and next to the ordering stations.
In addition to the selection of pastries and other baked goods from the Blue Ribbon, the new Jolly Holiday Bakery offers a surprisingly large selection of new offerings including Mickey-shaped chocolate tarts, cheesecakes, lemon-strawberry cupcakes, mini seasonal pies, fruit tarts, chocolate cream cheese bars and much more. While we'll only feature a selection of the new offerings here today, the fantastic Disney Food Blog has a very thorough listing and review (including photos) of just about all of the new pastries and food offerings.
We were a bit disappointed to see all of the hot food items sitting in the display case. It'd be nice to have items like the toasted cheese sandwich from the Jolly Holiday Combo or the angus beef sandwich prepared fresh, especially at the prices they're charging for the items. Still, hot sandwiches and quiches are warmed up when you order them.
We sampled the hot angus roast beef sandwich and the tomato basil soup Saturday night. The sandwich was a winner, with great melty cheese and a tasty horseradish sauce. Still, the sandwich was a touch cold in the center, but that's an issue that can be fixed by ordering it extra hot or by Disney adjusting the heating times. The sandwich is served with potato chips on the side, which are nothing more than a serving of the Disney-branded chips you can find sold in bags at outdoor vending carts throughout the park.
The soup was serviceable, but not particularly interesting in flavor. It felt a touch above Campbell's canned tomato soup, but not as good as a flavorful, quality home-made variation you'd find in a good restaurant. It's served with room-temperature breadstick. The soup is a decent option if you want a quick snack but don't want a sugary churro or a greasy turkey leg from a cart.
Other options include a chicken waldorf salad sandwich and tossed salads.
The menu also features a very tempting "Practically Perfect Punch" for $3.29 a cup. While a better option than soda, it's nothing more than Odwalla brand Pomegranate Limeade that you can pick up at your local grocery store. It's too bad something original couldn't have found its way onto the menu (the excellent non-alcoholic Schweitzer Falls found at Disneyland Hotel's Trader Sam's bar comes to mind).
Overall, it's great to have an operating foodservice location back at the old Plaza Pavilion. While the theme may err closer to Fantasyland than it does Main Street, the location looks gorgeous and the expanded food selection is much welcome.
Back in Frontierland, Disneyland capped off its extended holiday season with its first-ever Three Kings Day Celebration in Zocalo Park in Frontierland.
The Latino-targeted offering drew the attention of numerous domestic and international Spanish-speaking television and radio outlets and healthy crowds to the area over the weekend.
From the OC Register's Around Disney Blog:
New Disneyland holiday event targets Latino market
For the extended season, Disneyland officials decided to try out something new a three-day celebration aimed at a Latino-focused holiday.
On the first day Friday (today), officials were surprised at the amount of media interest in the Dia de Reyes Magos event: Fourteen Spanish-language television outlets, both international and national, either broadcast on site or aired live segments from Disneyland. One English language station, KTTV, also came out, as well as a few print journalists for a morning media demonstration.
We were pleasantly surprised, said Claudia Cespedes, associate marketing manager for the Disneyland Resort. It was so welcome. Everybody was really excited.
Plus, the event drew crowds when it opened to guests Friday morning.
Dia de Reyes, or Three Kings Day, is traditionally celebrated in Latin American countries 12 days after Christmas to commemorate the day when the three kings brought gifts to Jesus in Christianity. Disneylands version of the holiday includes traditional foods, entertainment by Mariachi Divas and folklorico dancers and kids activities in Frontierlands Zocalo Park.
Its kind of a fine line, Cespedes said. We want to be mindful and show the cultural tradition, more so than the religious part.
Dia de Reyes is part of Disneylands effort to market holidays to the Latino community. For the past two years, Disney also has reached out at Latino events to promote the Halloween season, bringing characters to perform and running a vote-for-your-favorite-villain campaign.
It is a part of our regular campaign. Whatever we do for the general market, we do for the Hispanic market, Cespedes said.
For Dia de Reyes, Disneyland is selling traditional foods: A mini Rosca de Reyes, a ring shaped sweet bread, is for sale on a cart for $5.50 each, as well as strawberry churros for $3.75. Two types of tamales are available at the Rancho del Zocalo Restaurante.
Visitors can pose for pictures with Mickey and Minnie Mouse dressed in festive attire, as well as the Three Caballeros, who are rarely seen in the park. [ FULL STORY ]
Tables with holiday-related displays explain the significance of the holiday.
Some decorations are held over from the Dia de los Muertos display that's found here in the fall.
The event really packs in a good amount into a rather small package. It's well-done, informative and the live entertainment and displays add some life to this corner of Frontierland.
It's great to see Disneyland add more of these small seasonal offerings in the parks. Frontierland's Three Kings Day and Dia de los Muertos offerings are nice additions that add a welcome cultural element to traditional holiday offerings. Hopefully Disney will continue to add seasonal offerings like this annual Mardi Gras and Lunar New Year celebrations would be a good start.
Below, video of the Grammy-award winning Mariachi Divas perform with Mexican folklorico dancers.
Face painting and coloring activities
Nearby, the Rancho del Zocalo Restaurante had themed foods for the Three Kings Day festivities.
Over in Fantasyland, the Matterhorn Bobsleds are now closed for an extended refurbishment. The closure will also include the installation of an all-new fleet of bobsleds.
The six-month closure is also expected to include a complete re-painting of the mountain.
The new lawyer-approved bobsleds will forgo the tandem-rider seating configuration and plentiful legroom for two three-seat bobsleds linked together.
These signs are now a thing of the past...
Below, a complete ride-through of the attraction from Saturday.
Construction continues on Buena Vista Street...
The tile roof is starting to go up at the Carthay Circle Theater.
Wrought-iron marquee
New trees installed in front of the Carthay Circle
Another look at the roof tiles
Back on Paradise Pier, the awfully tacky Midway Shops unexpectedly started disappearing behind construction walls last week. The Man Hat 'n' Beach shop facade and the side of the Sideshow Shirts facing the former Maliboomer area were the first sections to go, with their garish neon and pun-riddled signage quickly removed.
The obnoxious clown-faced jack-in-the-box facade is finally history!
All that remains is the yellow starburst.
The side of the Sideshow Shirts building is behind walls, too. It'll be interesting to see what is changed here. Pretty much anything should be an improvement over the plain stucco walls and simple neon "waves" that were here before.
The ATM has been moved to the front of the shop for now. All of the shops remain open during construction.
At Cars Land, the Cars 2 meet-and-greet has finally been removed, allowing for a clearer view down the main street of Radiator Springs.
Sarge's Surplus Hut
The rest of Mater's Junkyard Jamboree's string lighting looks to be in place now
In Downtown Disney, the La Brea Bakery is partially closed for remodel. The Bakery's "Express" side is completely closed, with construction walls surrounding it and its outdoor dining area. The dining location's full-service sit-down portion remains open.
During construction, you enter through a gate on the side of the outdoor patio on the side closes to World of Disney
Further into Downtown Disney, the Cupcake Store, previously located in the old Compass Books newsstand is moving into a new kiosk of its own near the LEGO store, in front of the Apricot Lane Boutique
Speaking of Compass Books, the bookstore and cafe is set to close later this spring. A pity - another great bookstore closing shop.
What'll be missed is Compass Books' nice selection of Disney-related books, including a selection of harder-to-find titles and unofficial titles that Disney doesn't offer in the parks.
Steps away from Compass Books, the Disneyland Hotel continues to get its finishing touches added now that the busy holiday season is over.
The cement in the hotel's main lobby entryway is getting textured and colorized.
You can already see some sections have their new color
Repaving is underway at the Harbor Boulevard bus drop off area.
And finally, the horrid and bulky Let the Memories Begin! marquee that was brought into the Main Entrance Plaza when that campaign started last year will finally leave Monday night. Good riddance.
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WEEKLY NEWS AND INFORMATION ROUND-UP Weekly Theme Park HoursJanuary 915, 2012
Disneyland Park Disney California Adventure Monday-Thursday: 10 am - 8 pm
Friday: 9 am - 12 midnight
Saturday-Sunday: 8 am - 12 midnight
Monday-Thursday: 10 am - 8 pm
Friday-Sunday: 10 am - 9 pm
For a complete listing of theme park hours, visit the Disneyland.com Theme Park Calendar
Expected Crowd Levels presented by TouringPlans.com Disneyland Park Disney California Adventure LOW-MEDIUM 1.16.7 out of 10 LOW-MEDIUM 2.16.8 out of 10
Closures and Refurbishment Schedule Disneyland Park
- Big Thunder Ranch: Closed to remove holiday overlay through January 18.
- Haunted Mansion: Closed to remove holiday overlay through January 23.
- Matterhorn Bobsleds: Closed for major refurbishment including the addition of new ride vehicles through June 14.
- "it's a small world": Closed to remove holiday overlay January 23 - February 2.
- Sailing Ship Columbia: Closed for refurbishment January 23 - February 17.
- Davy Crockett Explorer Canoes: Closed for one day, January 24.
- Blue Ribbon Bakery, Gibson Girl Ice Cream Parlor and Candy Palace: Food service locations and shops close January 2012 for major restaurant and shopping expansion projects affecting current spaces.
Disney California Adventure
- Redwood Creek Challenge Trail: Closed for refurbishment through January 27.
- Grizzly River Run: Closed for refurbishment January 23 - March 2.
- Soarin' Over California: Closed for refurbishment January 30 - February 3.
- Ghirardelli Chocolate Company and Soda Fountain: New Ghirardelli chocolate shop and soda fountain will open in the space formerly occupied by the Mission Tortilla Factory. New dining location opens late-spring 2012.
- Buena Vista Street: Re-themed main entrance including new Red Car Trolley attraction are under construction through summer 2012.
- Cars Land: New 12-acre land opens summer 2012.
Downtown Disney & Hotels of the Disneyland Resort
- Island Charters: Downtown Disney retail location closed permanently. A replacement has yet to be announced.
Join MiceChat's 7th Anniversary Celebration!
MiceChat is celebrating its 7th anniversary with an array of great events and meet-ups! Don't miss it!
MiceChat Celebrates 7 Years!
It all begins on Friday January 27, 2012. Join us on a very special one day Adventures By Disney "Hollywood Magic" trip that starts at the Walt Disney Studios and then takes you to other famous Hollywood locations with your MiceChat pals. We'll tour the Walt Disney Studios, see the famous Disney Archives, dine in the commissary and shop in the studio store. Then it's off to Hollywood where you'll tour the El Capitan and the Kodak Theaters (the latter the home of the Academy Awards) as well as other famous tinseltown and Sunset Strip sights and landmarks. The day wraps up with a cocktail reception on Malibu Beach at sunset. What better way to kick off the MiceChat anniversary weekend! The event is currently listed as SOLD OUT, BUT it is likely that we'll be able to add an additional 10 folks, so get your name in to Teresa Cory from Fairy Godmother Travel today: [email protected]
The fun continues on Saturday, January 28th, with the MiceChat Celebrity Breakfast at ESPN Zone. A wonderful buffet breakfast/meet and greet with Disney celebrities including Susan Egan (Broadway's Belle and the voice of Meg from Hercules), Disney author Sam Gennawey, Margaret Kerry (the original reference model and actress for Tinker bell), and other invited guests. The event will take place from 9am-11am, Saturday, January 28th at the fabulous ESPN Zone in Downtown Disney. And YES, the world famous, ESPN Zone Maple Bacon will be served! Following the breakfast we will spend the day in Disney California Adventure. CLICK HERE TO BUY YOUR TICKETS
The grand finale is on Sunday, January 29th which is our traditional Disneyland day with breakfast along the Rivers of America, a grand circle tour of the happiest place on earth and the classic noon meet at the right hand of Walt Disney himself. We hope you'll be able to join us. More details about the meets, events and special opportunities will be posted soon. CLICK HERE FOR UPDATED INFO ON THE FUN-FILLED WEEKEND
More Info: MiceChat 7th Anniversary Celebration
Regular tickets and Annual Passports valid for Leap Day event
Good news - Disney's 24-hour Leap Day Party will not require a special ticket; regular tickets and Annual Passports will be accepted.
Disneyland plans to hold 24-hour party
Disneyland will hold a 24-hour party on Leap Day next year as part of a promotion, Disney announced Saturday.
Disneyland will be open for 24 hours starting 6 a.m. Feb. 29 and ending 6 a.m. March 1, according to a Disney website. Disney made the announcement on Dick Clarks New Years Rockin Eve with Ryan Seacrest show on Saturday. Magic Kingdom in Florida also will have a 24-hour party.
As part of the One More Disney Day campaign, Disney also plans to give away a vacation package daily starting Sunday through Feb. 29.
This isnt the first time that Disneyland has been open overnight. In 1987, the park hosted a 60-hour party for the opening of Star Tours.
But Disney officials claim this will be the first time that both Disneyland and Magic Kingdom will be open 24 hours on the same day.
To celebrate, for the first time ever, the Magic Kingdom and Disneyland Parks will remain open for 24 hours on Leap Day, so that our guests can take advantage of every minute of their extra day to make memories with friends and family, said Tom Staggs, chairman of Walt Disney Parks and Resorts, in a statement.
Both regularly-priced tickets and annual passes can be used to enter the overnight party, said Erin Glover, a Disneyland Resort spokeswoman. The current cost for a one-day ticket is $80 for ages 10 and up.
No special activities or features have been planned so far.
Full Story: Around Disney: Disneyland plans to hold 24-hour party
$99 So Cal ticket deal returns
Details on the return of the 2-day $99 ticket deal.
SoCal residents can get deal on Disney parks
Disneyland Resort has started its annual promotion of discounting park tickets to Southern California residents: $99 for two days.
The price is the same as last years promotion.
Residents can pay $99 for two days of tickets, which can be used at one park per day, the company announced Wednesday morning.
Buyers can choose to visit both parks Disney California Adventure and Disneyland or go to the same park twice. For an extra $30, visitors can add a ticket for an extra day.
The regular cost of a single-day, single-park ticket is $80 for visitors ages 10 and up.
Local residents can use the SoCal ticket to attend the special 24-hour party on Leap Day, Feb. 29, at Disneyland, said John McClintock, a Disneyland Resort spokesman.
The tickets are valid today through June 9 and must be purchased by June 1. Tickets are blacked out during the busy spring-break days.
Full Story: Around Disney: SoCal residents can get deal on Disney parks
Alright, that wraps up this week's update. Thanks for reading and be sure to visit our fantastic sponsors over at TouringPlans and the Howard Johnson Anaheim when planning your next visit to Disneyland!
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See you at Disneyland!
- Andy
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text:
Congress president Sonia Gandhi gave an elaborate reply to BJP's charges about 60 years of Congress "misrule" and listed the work done by the party and projects implemented under her party's rule.
"While campaigning in different parts of the country, the chief minister of this state (Modi) claims that Congress never did anything for the nation during the last 60 years of its rule," Gandhi said, addresing her second rally of the day, in Gujarat.
Sonia listed several big ticket projects implemented by the Congress over the years.
"Every major dam, industries, educational institutes, infrastructure and railways which you see in the nation today -- from where did this come? Have all these things dropped from the sky," Gandhi said, replying to Gujarat Chief Minister Narendra Modi's charges, without taking his name.
"White revolution, telecom revolution and nuclear projects -- these are the results of Congress policy and efforts over the years," she said.
Speaking about Gujarat's development, she said that the Congress had a hand in it as well.
"Who laid the basis of Gujarat's industrial revolution? Who set up projects like ONGC, Dharoi dam, CIPU (irrigation scheme)? Was it the BJP?" Sonia asked.
"Ask them if it would have been possible without the Congress? There are some parties which only level false charges. BJP is crossing every limit to get to the chair of the PM. A climate of hatred has been spread throughout the country. It is a matter of concern for me if people spread lies to acquire power," Sonia said.
"Can we hand over Indian democracy into the hands of such people," Sonia asked the crowd, and also targeted Modi for his statements that he would keep criminals out from politics.
"They say that they we will eliminate criminal elements from parliament, but why you have not ousted criminals from Gujarat (cabinet)" Sonia asked, referring apparently to ministers like Babu Bokhiria who has been convicted by the court and Purshottam Solanki who faces a case in the fisheries scam, but continues to be part of Modi's cabinet.


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