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Nature Communications Sep 2022The integration of large-scale two-dimensional (2D) materials onto semiconductor wafers is highly desirable for advanced electronic devices, but challenges such as...
The integration of large-scale two-dimensional (2D) materials onto semiconductor wafers is highly desirable for advanced electronic devices, but challenges such as transfer-related crack, contamination, wrinkle and doping remain. Here, we developed a generic method by gradient surface energy modulation, leading to a reliable adhesion and release of graphene onto target wafers. The as-obtained wafer-scale graphene exhibited a damage-free, clean, and ultra-flat surface with negligible doping, resulting in uniform sheet resistance with only ~6% deviation. The as-transferred graphene on SiO/Si exhibited high carrier mobility reaching up ~10,000 cm V s, with quantum Hall effect (QHE) observed at room temperature. Fractional quantum Hall effect (FQHE) appeared at 1.7 K after encapsulation by h-BN, yielding ultra-high mobility of ~280,000 cm V s. Integrated wafer-scale graphene thermal emitters exhibited significant broadband emission in near-infrared (NIR) spectrum. Overall, the proposed methodology is promising for future integration of wafer-scale 2D materials in advanced electronics and optoelectronics.
PubMed: 36109519
DOI: 10.1038/s41467-022-33135-w -
Drug Design, Development and Therapy 2013The objective of this study was to prepare a novel fentanyl wafer formulation by a freeze-drying method, and to evaluate its in vitro and in vivo release... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The objective of this study was to prepare a novel fentanyl wafer formulation by a freeze-drying method, and to evaluate its in vitro and in vivo release characteristics, including its bioavailability via the sublingual route.
METHODS
The wafer formulation was prepared by freeze-drying an aqueous dispersion of fentanyl containing sodium carboxymethylcellulose and amylogum as matrix formers. Uniformity of weight, friability, and dissolution testing of the fentanyl wafer was achieved using standard methods, and the residual moisture content was measured. The fentanyl wafer was also examined using scanning electron microscopy and x-ray diffraction. The absolute bioavailability of the fentanyl wafer was evaluated in 11 opioid-naïve adult female patients using a randomized crossover design.
RESULTS
In vitro release showed that almost 90% of the fentanyl dissolved in one minute. In vivo, the first detectable plasma fentanyl concentration was observed after 3.5 minutes and the peak plasma concentration between 61.5 and 67 minutes. The median absolute bioavailability was 53.0%.
CONCLUSION
These results indicate that this wafer has potential as an alternative sublingual fentanyl formulation.
Topics: Administration, Sublingual; Adult; Aged; Analgesics, Opioid; Biological Availability; Carboxymethylcellulose Sodium; Cross-Over Studies; Excipients; Female; Fentanyl; Freeze Drying; Humans; Microscopy, Electron, Scanning; Middle Aged; Pilot Projects; Solubility; X-Ray Diffraction; Young Adult
PubMed: 23596347
DOI: 10.2147/DDDT.S42619 -
Micromachines Oct 2021For the integration of a reactive multilayer system (iRMS) with a high exothermic reaction enthalpy as a heat source on silicon wafers for low-temperature bonding in the...
For the integration of a reactive multilayer system (iRMS) with a high exothermic reaction enthalpy as a heat source on silicon wafers for low-temperature bonding in the 3D integration and packaging of microsystems, two main conflicting issues should be overcome: heat accumulation arising from the layer interface pre-intermixing, which causes spontaneous self-ignition during the deposition of the system layers, and conductive heat loss through the substrate, which leads to reaction propagation quenching. In this work, using electron beam evaporation, we investigated the growth of a high exothermic metallic Pd/Al reactive multilayer system (RMS) on different Si-wafer substrates with different thermal conduction, specifically a bare Si-wafer, a RuO or PdO layer buffering Si-wafer, and a SiO-coated Si-wafer. With the exception of the bare silicon wafer, the RMS grown on all other coated wafers underwent systematic spontaneous self-ignition surging during the deposition process once it reached a thickness of around 1 μm. This issue was surmounted by investigating a solution based on tuning the output energy by stacking alternating sections of metallic reactive multilayer Pd/Al and Ni/Al systems that have a high and medium enthalpy of exothermic reactions, respectively. This heterostructure with a bilayer thickness of 100 nm was successfully grown on a SiO-coated Si-wafer to a total thickness of 3 μm without any spontaneous upsurge of self-ignition; it could be electrically ignited at room temperature, enabling a self-sustained propagating exothermic reaction along the reactive patterned track without undergoing quenching. The results of this study will promote the growth of reactive multilayer systems by electron beam evaporation processing and their potential integration as local heat sources on Si-wafer substrates for bonding applications in microelectronics and microsystems technology.
PubMed: 34683323
DOI: 10.3390/mi12101272 -
National Science Review Jun 2022The 2D semiconductor of MoS has great potential for advanced electronics technologies beyond silicon. So far, high-quality monolayer MoS wafers have been available and...
The 2D semiconductor of MoS has great potential for advanced electronics technologies beyond silicon. So far, high-quality monolayer MoS wafers have been available and various demonstrations from individual transistors to integrated circuits have also been shown. In addition to the monolayer, multilayers have narrower band gaps but improved carrier mobilities and current capacities over the monolayer. However, achieving high-quality multi-layer MoS wafers remains a challenge. Here we report the growth of high-quality multi-layer MoS 4-inch wafers via the layer-by-layer epitaxy process. The epitaxy leads to well-defined stacking orders between adjacent epitaxial layers and offers a delicate control of layer numbers up to six. Systematic evaluations on the atomic structures and electronic properties were carried out for achieved wafers with different layer numbers. Significant improvements in device performances were found in thicker-layer field-effect transistors (FETs), as expected. For example, the average field-effect mobility ( ) at room temperature (RT) can increase from ∼80 cm·V·s for monolayers to ∼110/145 cm·V·s for bilayer/trilayer devices. The highest RT of 234.7 cm·V·s and record-high on-current densities of 1.70 mA·μm at = 2 V were also achieved in trilayer MoS FETs with a high on/off ratio of >10. Our work hence moves a step closer to practical applications of 2D MoS in electronics.
PubMed: 35769232
DOI: 10.1093/nsr/nwac077 -
Iranian Journal of Pharmaceutical... 2021Wound healing is a complex process and is influenced by different factors. Aimed to enhance the wound healing procedure, the Moxifloxacin bilayer wafer was designed,...
Wound healing is a complex process and is influenced by different factors. Aimed to enhance the wound healing procedure, the Moxifloxacin bilayer wafer was designed, optimized and evaluated as an advanced wound healing dressing. The wafers were prepared by the lyophilization and casting method. Optimization was done according to the results of bioadhesion force, swelling index, release rate, T and T (the time to reach 40% and 90% of release). The optimized wafer was evaluated against and efficacy using the disc diffusion method and histologic evaluation after application on the wound. The optimized formulation contained HPMC, MC, gelatin and PVP with mounts of 50 mg, 25 mg, 2 mg and 10 mg respectively. The hydrophilic bilayer wafer is adhered to the wound up to the end of wound healing. Application of optimized formulation led to the healing of wound 6 days faster without any sign of infection. The application of this wafer promoted wound healing and epithelium regeneration without any inflammation.
PubMed: 34903988
DOI: 10.22037/ijpr.2021.112962.14081 -
Microsystems & Nanoengineering 2021I have been developing MEMS (microelectromechanical systems) technology and supporting the industry through collaboration. A facility was built in house on a 20 mm... (Review)
Review
I have been developing MEMS (microelectromechanical systems) technology and supporting the industry through collaboration. A facility was built in house on a 20 mm square wafer for use in prototyping MEMS and ICs (integrated circuits). The constructed MEMS devices include commercialized integrated capacitive pressure sensors, electrostatically levitated rotational gyroscopes, and two-axis optical scanners. Heterogeneous integration, which is a MEMS on an LSI (large-scale integration), was developed for sophisticated systems using LSI made in a foundry. This technology was applied for tactile sensor networks for safe robots, multi FBAR filters on LSI, active-matrix multielectron emitter arrays, and so on. The facility used to produce MEMS on 4- and 6-inch wafers was developed based on an old semiconductor factory and has been used as an open hands-on access facility by many companies. Future directions of MEMS research are discussed.
PubMed: 34567772
DOI: 10.1038/s41378-021-00290-x -
Patient Preference and Adherence 2016Polifeprosan 20 with carmustine (GLIADEL) polymer implant wafer is a biodegradable compound containing 3.85% carmustine (BCNU, bischloroethylnitrosourea) implanted in... (Review)
Review
Polifeprosan 20 with carmustine (GLIADEL) polymer implant wafer is a biodegradable compound containing 3.85% carmustine (BCNU, bischloroethylnitrosourea) implanted in the brain at the time of planned tumor surgery, which then slowly degrades to release the BCNU chemotherapy directly into the brain thereby bypassing the blood-brain barrier. Carmustine implant wafers were demonstrated to improve survival in randomized placebo-controlled trials in patients undergoing a near total resection of newly diagnosed or recurrent malignant glioma. Based on these trials and other supporting data, carmustine wafer therapy was approved for use for newly diagnosed and recurrent malignant glioma in the United States and the European Union. Adverse events are uncommon, and as this therapy is placed at the time of surgery, it does not add to patient treatment burden. Nevertheless, this therapy appears to be underutilized. This article reviews the evidence for a favorable therapeutic ratio for the patient and the potential barriers. Consideration of these issues is important for optimal use of this therapeutic approach and may be important as this technology and other local therapies are further developed in the future.
PubMed: 27920506
DOI: 10.2147/PPA.S93020 -
Drug Design, Development and Therapy 2015Standard treatment for high-grade glioma (HGG) includes surgery followed by radiotherapy and/or chemotherapy. Insertion of carmustine wafers into the resection cavity as... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Standard treatment for high-grade glioma (HGG) includes surgery followed by radiotherapy and/or chemotherapy. Insertion of carmustine wafers into the resection cavity as a treatment for malignant glioma is currently a controversial topic among neurosurgeons. Our meta-analysis focused on whether carmustine wafer treatment could significantly benefit the survival of patients with newly diagnosed glioblastoma multiforme (GBM).
METHOD
We searched the PubMed and Web of Science databases without any restrictions on language using the keywords "Gliadel wafers", "carmustine wafers", "BCNU wafers", or "interstitial chemotherapy" in newly diagnosed GBM for the period from January 1990 to March 2015. Randomized controlled trials (RCTs) and cohort studies/clinical trials that compared treatments designed with and without carmustine wafers and which reported overall survival or hazard ratio (HR) or survival curves were included in this study. Moreover, the statistical analysis was conducted by the STATA 12.0 software.
RESULTS
Six studies including two RCTs and four cohort studies, enrolling a total of 513 patients (223 with and 290 without carmustine wafers), matched the selection criteria. Carmustine wafers showed a strong advantage when pooling all the included studies (HR = 0.63, 95% confidence interval (CI) = 0.49-0.81; P = 0.019). However, the two RCTs did not show a statistical increase in survival in the group with carmustine wafer compared to the group without it (HR = 0.51, 95% CI = 0.18-1.41; P = 0.426), while the cohort studies demonstrated a significant survival increase (HR = 0.59, 95% CI = 0.44-0.79; P < 0.0001).
CONCLUSION
Carmustine-impregnated wafers play a significant role in improving survival when used for patients with newly diagnosed GBM. More studies should be designed for newly diagnosed GBM in the future.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Brain Neoplasms; Carmustine; Chemistry, Pharmaceutical; Decanoic Acids; Dosage Forms; Glioblastoma; Humans; Middle Aged; Neoplasm Grading; Polyesters; Risk Factors; Survival Analysis; Time Factors; Treatment Outcome; Young Adult
PubMed: 26170620
DOI: 10.2147/DDDT.S85943 -
Micromachines Aug 2016Two stacked integration methods have been developed to enable advanced microsystems of microelectromechanical systems (MEMS) on large scale integration (LSI). One is a...
Two stacked integration methods have been developed to enable advanced microsystems of microelectromechanical systems (MEMS) on large scale integration (LSI). One is a wafer level transfer of MEMS fabricated on a carrier wafer to a LSI wafer. The other is the use of electrical interconnections using through-Si vias from the structure of a MEMS wafer on a LSI wafer. The wafer level transfer methods are categorized to film transfer, device transfer connectivity last, and immediate connectivity at device transfer. Applications of these transfer methods are film bulk acoustic resonator (FBAR) on LSI, lead zirconate titanate (Pb(Zr,Ti)O₃) (PZT) MEMS switch on LSI, and surface acoustic wave (SAW) resonators on LSI using respective methods. A selective transfer process was developed for multiple SAW filters on LSI. Tactile sensors and active matrix electron emitters for massive parallel electron beam lithography were developed using the through-Si vias.
PubMed: 30404308
DOI: 10.3390/mi7080137 -
Drug Delivery Nov 2018The current study aimed to investigate the effectiveness of a developed sodium alginate and polyvinylpyrrolidone K-25 (PVP K-25) polymeric wafer for the co-delivery of...
The current study aimed to investigate the effectiveness of a developed sodium alginate and polyvinylpyrrolidone K-25 (PVP K-25) polymeric wafer for the co-delivery of ketorolac and lidocaine to soft tissues for healing and pain control following gingivectomy. Nine ketorolac/lidocaine lyophilized wafers were formulated and assessed for their hydration capacity, mucoadhesion ability and in vitro release profile to select the optimum system for further clinical investigation. Wafer F6 containing 2:1 sodium alginate to PVP K-25 and 10% glycerol showed optimum properties and was selected for the clinical study. Twenty patients were included in the study and the ketorolac/lidocaine wafer was assessed versus a market product. Visual pain analog was evaluated daily for the first week and wound healing index was evaluated for one week, two weeks and one month following the procedure. The developed ketorolac/lidocaine polymeric wafer proved to be an effective method of reducing pain and discomfort together with enhancing wound healing following gingivectomy.
Topics: Adolescent; Adult; Alginates; Anesthetics, Local; Anti-Inflammatory Agents, Non-Steroidal; Drug Delivery Systems; Female; Gingivectomy; Glucuronic Acid; Hexuronic Acids; Humans; Ketorolac; Lidocaine; Male; Mouth Mucosa; Pain; Pain Measurement; Polymers; Povidone; Wound Healing; Young Adult
PubMed: 29226726
DOI: 10.1080/10717544.2017.1413445