Incidence of low-level viremia and its impact on virologic failure among people living with HIV who started an integrase strand transfer inhibitors: a longitudinal cohort study.

BACKGROUND: Low-level viremia (LLV) has been identified as a potential precursor to virologic failure (VF), yet its clinical implications, particularly within the context of Integrase Strand Transfer Inhibitors (INSTIs)-based regimens, remain insufficiently explored. The study aimed to investigate the relationship between LLV and VF within ART-naïve patients on INSTIs-based regimens in China. METHODS: A longitudinal cohort study was conducted with ART-naïve patients aged ≥ 18 years at Beijing Ditan Hospital, under the Chinese National Free Antiretroviral Treatment Program (NFATP). The LLV was defined as a viral load (VL) ranging from 50 to 199 copies/mL after six months of ART initiation, and VF as a VL ≥ 200 copies/mL. Sensitive analyses were also performed, defining LLV as 50-999 copies/mL and VF as exceeding 1000 copies/mL. Multivariate logistic regression, Kaplan-Meier (KM) curve, and Generalized Estimating Equation (GEE) models were used to evaluate the risk factors associated with LLV and VF events. RESULTS: The study involved 830 ART-naïve patients, comprising 600 in the INSTIs group and 230 in the protease inhibitors (PIs) group. LLV events were observed in 10.4% of patients on PIs-based regimens and and 3.2% on INSTIs-based regimens (P < 0.001). INSTIs-based regimens demonstrated a protective effect against LLV events (aHR = 0.27, 95% CI 0.137-0.532). VF events occurred in 10.9% of patients on PIs-based regimens and 2.0% on INSTIs-based regimens, respectively (P < 0.001). The occurrence of LLV events significantly increased the risk of VF by 123.5% (95% CI 7.5%-364.4%), while the integrase inhibitors were associated with a 76.9% (95% CI 59.1%-86.9%) reduction in VF risk. CONCLUSION: Our findings indicate that INSTIs-based regimens are critical protective factors against LLV and subsequent VF. These results underscore the importance of HIV viral load monitoring to ensuring effective treatment outcomes, highlighting the necessity for prompt and precise monitoring to refine HIV treatment methodologies.

Efficacy and Safety of Fractional CO2 Laser Combined with Halometasone Cream for Treatment of Moderate-to-Severe Chronic Hand Eczema: A Prospective, Single-Center, Parallel-Group, Open-Label Randomized Trial.

INTRODUCTION: The purpose of this study was to assess the efficacy and safety of fractional CO2 laser combined with halometasone cream in patients with moderate-to-severe chronic hand eczema (CHE). METHODS: A prospective, single-center, parallel-group, open-label randomized trial including 67 patients with moderate-to-severe CHE was carried out. Patients were randomly assigned to group A (n = 33, fractional CO2 laser once every 4 weeks 1-2 times and halometasone cream twice daily for 8 weeks) or group B (n = 34, halometasone cream alone twice daily for 8 weeks). The primary endpoint was the proportion of patients achieving treatment success at week 12 in each group. Secondary endpoints included differences between groups in the change of hand eczema severity index (HECSI), patient global assessment (PaGA), dermatology life quality index (DLQI), and quality of life in hand eczema questionnaire (QOLHEQ) from baseline to week 12. Relapse rate and adverse effects were also recorded. RESULTS: A total of 29 patients in each group completed the trial. At week 12, the treatment success rate was 62.1% (18/29) in group A and 27.6% (8/29) in group B (p = 0.009). At week 12, HECSI, PaGA, DLQI, and QOLHEQ all decreased compared with baseline in both groups (p < 0.05). HECSI, DLQI, and QOLHEQ decreased more in group A than group B (p = 0.014, 0.010, and 0.014, respectively), but there was no significant difference in change of PaGA between the two groups (1.0 versus 3.0, p = 0.419). Among patients achieving treatment success, 11.1% (2/18) patients in group A and 50.0% (4/8) patients in group B relapsed at week 24 (p = 0.011). Skin pigmentation was the most common adverse effect. CONCLUSIONS: For patients with moderate-to-severe CHE, fractional CO2 laser combined with halometasone cream is more effective than halometasone cream alone, with few adverse effects. TRIAL REGISTRATION NUMBER: ChiCTR2100051948.

High-Performance Shortwave Infrared Detector Based on Multilayer Carbon Nanotube Films.

Carbon nanotube (CNT) is an ideal candidate material for shortwave infrared (SWIR) detectors due to its large band gap tunability, strong infrared light absorption, and high mobility. Furthermore, the photodetectors based on CNT can be prepared on any substrate using a low-temperature process, which is conducive to three-dimensional (3D) integration. However, owing to the absorption limitation (<2%) of a single-layer network CNT film with low density, the photodetectors of CNT film show low photocurrent responsivity and detectivity. In this paper, we optimize the thickness of the high-purity semiconducting network CNT films to increase the photocurrent responsivity of the photodetectors. When the thickness of network CNT film is about 5 nm, the responsivity of the zero-bias voltage can reach 32 mA/W at 1800 nm wavelength. Then, using stacked CNT films and contact electrode design, the photodetectors exhibit a maximum responsivity of 120 mA/W at 1800 nm wavelength. The photodetectors with stacked CNT films and local n-type channel doping demonstrated a wide response spectral range of 1200-2100 nm, a peak detectivity of 3.94 × 109 Jones at room temperature, and a linear dynamic range over 118 dB. Moreover, the peak detectivity is over 2.27 × 1011 Jones when the temperature is 180 K. Our work demonstrates the potential of the CNT film for future SWIR imaging at a low cost.

Thirteen-year viral suppression and immunologic recovery of LPV/r-based regimens in pediatric HIV treatment: a multicenter cohort study in resource-constrained settings of China.

Background: Antiretroviral Therapy (ART) in children remains challenging due to resource-constrained settings. We conducted a 13-year, prospective, multicenter cohort study on the effectiveness and safety of LPV/r-based regimens in ART-naive and ART-experienced children. Methods: From January 2008 to May 2021, children living with HIV-1 were recruited with LPV/r-based regimens from 8 clinical research sites in 6 provinces in China. Effectiveness outcomes were virologic failure (defined as at least two consecutive measurements of VL > 200 copies/mL after 6 months of ART) and immune response (defined as CD4% recovered to more than 25% after 12 months of treatment). The safety outcomes were treatment-related grade 2-4 adverse events and abnormal laboratory test results. Results: A total of 345 ART-naïve children and 113 ART-experienced children were included in this cohort study. The median follow-up time was 7.3 (IQR 5.5-10.5) years. The incidence density of virologic failure was 4.1 (95% CI 3.3-4.9) per 100 person-years in ART-naïve children and 5.0 (95% CI 3.5-6.5) per 100 person-years in ART-experienced children. Kaplan Meyer (KM) curve analysis showed children with ART experience were at a higher risk of virologic failure (p < 0.05). The risk factors of virologic failure in ART-naïve children were clinic setting in rural hospitals (aHR = 2.251, 1.108-4.575), annual missed dose times >5 days of LPV intake (aHR = 1.889, 1.004-3.554); The risk factor of virologic failure in ART-experienced children was missed dose times >5 days (aHR = 2.689, 1.299-5.604) and mother as caregivers for ART administration (aHR = 0.475, 0.238-0.948). However, during long-term treatment, viral suppression rates between ART-naïve and ART-experienced children remained similar. No significant differences were observed in the immune response, treatment-related grade 2-4 events, and abnormal laboratory test results between ART-naïve children and ART-experienced children. Conclusion: Our research underscores that with consistent, long-term treatment of LPV/r-based regimens, ART-experienced children can achieve therapeutic outcomes comparable to ART-naïve children. It provides crucial insights on LPV/r-based regimens in pediatric HIV treatment, especially in resource-limited settings where high-cost Integrase Strand Transfer Inhibitors (INSTs) are inaccessible. This evidence-based understanding provides an essential addition to the global therapeutic strategies for pediatric HIV treatment.

Carbon nanotube-based flexible high-speed circuits with sub-nanosecond stage delays.

High-speed flexible circuits are required in flexible systems to realize real-time information analysis or to construct wireless communication modules for emerging applications. Here, we present scaled carbon nanotube-based thin film transistors (CNT-TFTs) with channel lengths down to 450 nm on 2-µm-thick parylene substrates, achieving state-of-the-art performances of high on-state current (187.6 µA µm-1) and large transconductance (123.3 µS µm-1). Scaling behavior analyses reveal that the enhanced performance introduced by scaling is attributed to channel resistance reduction while the contact resistance (180 ± 50 kΩ per tube) remains unchanged, which is comparable to that achieved in devices on rigid substrates, indicating great potential in ultimate scaled flexible CNT-TFTs with high performance comparable to their counterparts on rigid substrates where contact resistance dominates the performance. Five-stage flexible ring oscillators are built to benchmark the speed of scaled devices, demonstrating a 281 ps stage delay at a low supply voltage of 2.6 V.

An epidermal electronic system for physiological information acquisition, processing, and storage with an integrated flash memory array.

Epidermal electronic systems that simultaneously provide physiological information acquisition, processing, and storage are in high demand for health care/clinical applications. However, these system-level demonstrations using flexible devices are still challenging because of obstacles in device performance, functional module construction, or integration scale. Here, on the basis of carbon nanotubes, we present an epidermal system that incorporates flexible sensors, sensor interface circuits, and an integrated flash memory array to collect physiological information from the human body surface; amplify weak biosignals by high-performance differential amplifiers (voltage gain of 27 decibels, common-mode rejection ratio of >43 decibels, and gain bandwidth product of >22 kilohertz); and store the processed information in the memory array with performance on par with industrial standards (retention time of 108 seconds, program/erase voltages of ±2 volts, and endurance of 106 cycles). The results shed light on the great application potential of epidermal electronic systems in personalized diagnostic and physiological monitoring.

Efficacy and Safety of 5% Minoxidil Alone, Minoxidil Plus Oral Spironolactone, and Minoxidil Plus Microneedling on Female Pattern Hair Loss: A Prospective, Single-Center, Parallel-Group, Evaluator Blinded, Randomized Trial.

Background: The efficacy of topical minoxidil (MX) alone on female pattern hair loss (FPHL) is limited. Combination therapy based on topical MX is currently expected to provide better outcomes. Objectives: This study aimed to assess whether the combined therapies including MX plus oral spironolactone (SPT) and MX plus microneedling (MN) have advantages in efficacy and safety over topical MX alone on mild-to-moderate FPHL with normal hormone levels in the blood and regular menstrual cycle. Methods: A prospective, single-center, parallel-group, evaluator blinded, randomized trial including 120 non-menopause women with proven FPHL (Sinclair class II-III) was performed in China. Patients were randomly assigned to three groups, namely, the MX group (5% topical MX alone, once daily), the MX + SPT group (MX plus SPT 80-100 mg daily), and the MX+MN group (MX plus MN every 2 weeks, 12 sessions). The change from the baseline to week 24 was assessed in hair growth (hair density and diameter under dermoscope), scalp tissue structure (epidermal thickness, dermis thickness, and average hair follicle diameter under ultrasound biomicroscopy), physician's global assessment (using a 7-point global-assessment scale and Sinclair's stage change), patient evaluation (Women's Androgenetic Alopecia Quality of Life Questionnaire and Sinclair's hair-shedding score) and side effects. Results: In total, 115 participants completed the trial. At week 24, the hair density increased most in MX + MN group and increased least in MX group (p < 0.001 for MX + MN group vs. MX + SPT group; p = 0.009 for MX + SPT group vs. MX group). The hair shaft diameter significantly increased in all groups (p < 0.001, respectively), but there were no significant differences among the three groups (p = 0.905). The epidermal thickness and average hair follicle diameter only increased in MX + MN group. Dermis thickness increased in all groups, but there were no significant differences among the three groups. Both physician's and patient assessments showed improvement in all three groups. Scalp pruritus was the most common side effect. The MX + SPT group had the most reported adverse effects. Limitations: The main limitations of this study are the relatively small sample size, the exclusion of severe FPHL patients, and the potential bias from unblinded treatments among the 3 groups. Conclusion: Topical MX combined with MN is a better choice than either MX plus oral SPT or MX alone for the treatment of mild-to-moderate FPHL patients.

Efficacy and Safety of Long-Pulsed 755-nm Alexandrite Laser for Keratosis Pilaris: A Split-Body Randomized Clinical Trial.

INTRODUCTION: Keratosis pilaris (KP) is a disfiguring disease and is resistant to treatment. Several treatment methods are available, but the efficacy is limited. This prospective, rater-blinded, split-body comparative study investigated the efficacy and safety of long-pulsed 755-nm alexandrite laser in the treatment of KP. METHODS: Twenty-two patients with KP of bilateral arms were enrolled in this study. All participants were randomized and treated with a long-pulsed 755-nm alexandrite laser on the left or right arm in four sessions held 3 weeks apart. The unified moisturizing lotion was applied on both left and right arms once a day. Physicians' assessment scores and patients' self-assessment scores were recorded, and skin imaging changes in dermoscopy, high-frequency ultrasound, and skin biopsy were obtained at baseline and 4 weeks after the fourth treatment. RESULTS: Of the 21 patients who completed the study, 15 were women and 6 were men. At 4 weeks after the fourth treatment, the laser side showed significantly lower total (2.0 versus 4.5), roughness (1.0 versus 2.0), and redness (1.0 versus 2.0) scores according to physicians' assessment (all P < 0.05). Furthermore, the laser side showed significantly lower total (2.0 versus 4.0), roughness (1.0 versus 2.0), and redness scores (1.0 versus 2.0) according to the patients' self-assessment (all P < 0.05). The proportions of patients who achieved dermoscopically and ultrasonographically showed excellent improvements in follicular plugs (57.1% versus 14.3%), perifollicular erythema (52.4% versus 9.5%), perifollicular hyperpigmentation (47.6% versus 14.3%), and the number of epidermal bulges (57.1% versus 19.1%) in the laser side was significantly higher than those who achieved such improvements in the control side (all P < 0.05). Histopathology showed that the follicular plugs and inflammatory cell infiltration were improved at the final visit. Three patients exhibited reversible postinflammatory hyperpigmentation. CONCLUSION: Long-pulsed 755-nm alexandrite laser treatment is effective and safe in treating both skin roughness and redness in KP. TRIAL REGISTRATION NUMBER: ChiCTR2100054489.

Efficacy of Microneedling Combined With Local Application of Human Umbilical Cord-Derived Mesenchymal Stem Cells Conditioned Media in Skin Brightness and Rejuvenation: A Randomized Controlled Split-Face Study.

Background: Fighting skin aging signs is one of the major challenges of the 21st century, recently, mesenchymal stem cells (MSCs) and microneedling (MN) have been applied for anti-aging. This study aims to evaluate the efficacy of the combination of MN and human umbilical cord-derived mesenchymal stem cells conditioned media (hUC-MSCs-CM) in skin brightness and rejuvenation. Methods: Thirty volunteers with facial skin aging were recruited for the randomized, controlled split-face study. The left and right sides of the face were randomly applied with saline via MN or hUC-MSCs-CM via MN. Five sessions were performed for each volunteer at 2-week intervals. Two dermatologists evaluated the clinical improvement, in terms of skin brightness and texture. A satisfaction score based on a self-evaluation questionnaire was recorded at 2 weeks after the last treatment. The objective evaluation was recorded before the first treatment, and at 2 weeks after the last treatment. Results: Twenty-eight volunteers with a mean (SD) age of 41 (6.54) years old completed the trial. The investigator's assessment for skin brightness and texture, and the self-satisfaction score revealed statistically better effects in hUC-MSCs-CM -plus-MN group than in MN alone (MN saline) group. No severe side effects were reported during the whole study period. Compared to MN alone group, the objective assessment revealed significant improvements in skin brightness (reduced melanin index, ultraviolet spots, and brown spots) and skin texture (reduced wrinkles and pores, and increased skin elasticity) in hUC-MSCs-CM-plus-MN group, while there were no obvious differences in skin hydration, trans-epidermal water loss, and the erythema index. Conclusion: The combination of hUC-MSCs-CM and MN exhibite anti-aging efficacy, and this could be used for facial rejuvenation in the future.

Carbon Nanotube-Based Flexible Ferroelectric Synaptic Transistors for Neuromorphic Computing.

Biological nervous systems evolved in nature have marvelous information processing capacities, which have great reference value for modern information technologies. To expand the function of electronic devices with applications in smart health monitoring and treatment, wearable energy-efficient computing, neuroprosthetics, etc., flexible artificial synapses for neuromorphic computing will play a crucial role. Here, carbon nanotube-based ferroelectric synaptic transistors are realized on ultrathin flexible substrates via a low-temperature approach not exceeding 90 °C to grow ferroelectric dielectrics in which the single-pulse, paired-pulse, and repetitive-pulse responses testify to well-mimicked plasticity in artificial synapses. The long-term potentiation and long-term depression processes in the device demonstrate a dynamic range as large as 2000×, and 360 distinguishable conductance states are achieved with a weight increase/decrease nonlinearity of no more than 1 by applying stepped identical pulses. The stability of the device is verified by the almost unchanged performance after the device is kept in ambient conditions without additional passivation for 240 days. An artificial neural network-based simulation is conducted to benchmark the hardware performance of the neuromorphic devices in which a pattern recognition accuracy of 95.24% is achieved.

High-Performance Carbon Nanotube-Based Transient Complementary Electronics.

Transient electronics is an emerging class of electronic devices that can physically degrade or disintegrate after a stable period of service, showing a vast prospect in applications of "green" consumer electronics, hardware-secure devices, medical implants, etc. Complementary metal-oxide-semiconductor (CMOS) technology is dominant in integrated circuit design for its advantages of low static power consumption, high noise immunity, and simple design layout, which also work and are highly preferred for transient electronics. However, the performance of complementary transient electronics is severely restricted by the confined selection of transient materials and compatible fabrication strategies. Here, we report the realization of high-performance transient complementary electronics based on carbon nanotube thin films via a reliable electrostatic doping method. Under a low operating voltage of 2 V, on a 1.5 µm-thick water-soluble substrate made of poly(vinyl alcohol), the width-normalized on-state currents of the p-type and n-type transient thin-film transistors (TFTs) reach 4.5 and 4.7 µA/µm, and the width-normalized transconductances reach 2.8 and 3.7 µS/µm, respectively. Meanwhile, these TFTs show small subthreshold swings no more than 108 mV/dec and current on/off ratios above 106 with good uniformity. Transient CMOS inverters, as basic circuit components, are demonstrated with a voltage gain of 24 and a high noise immunity of 67.4%. Finally, both the degradation of the active components and the disintegration of the functional system are continuously monitored with nontraceable remains after 10 and 5 h, respectively.

Case Report: The First Reported Case of Bullous Lichen Planus-Systemic Lupus Erythematosus Overlap Syndrome.

Introduction: Lichen planus/lupus erythematosus overlap syndrome is rarely seen in the clinic and has the characteristic clinical manifestations, histopathology, and immunopathology of lichen planus (LP) and lupus erythematosus (LE). This is the first reported case of bullous lichen planus (BLP)/systemic lupus erythematosus (SLE) overlap syndrome with hair loss as the first symptom. Case Presentation: A 48-year-old female presented with alopecia for half a year, and skin lesions accompanied by itching on her face, trunk, and limbs for 3 months. She had a history suggestive of photosensitivity. Laboratory tests and histopathology were performed for diagnosis. Histopathologic features of the upper arm and back of the hand were consistent with BLP, whereas the scalp lesion indicated LE. Laboratory examination indicated positive for antinuclear antibody (ANA) (1:160), leukopenia, increased urinary protein, decreased C3/C4, and normal BP180. The patient was given glucocorticoid combined with acitretin and immunosuppressive therapy after a definite diagnosis of BLP/SLE overlap syndrome. The lesions of the patient disappeared and some hair had regrown during the two years of follow-up. Conclusion: This is the first reported case of BLP/SLE overlap syndrome which responded well to glucocorticoids, retinoids, and immunosuppressive drugs. Multiple biopsies from characteristic lesions will guide doctors to avoid misdiagnoses and delayed treatment.

Comparison of the Efficacy of Melasma Treatments: A Network Meta-Analysis of Randomized Controlled Trials.

Background: Melasma is an acquired pigmentation disorder with challenges in treatment because of its refractory nature and high risk of recurrence. Objectives: This study aimed to compare the efficacy and side effects of 14 common therapies for melasma using a systematic review and network meta-analysis (NMA). Methods: The PubMed, Embase, and Cochrane Library databases were searched till December 2020 using the melasma area and severity index as a therapeutic index. A total of 59 randomized controlled trials (RCTs) met the inclusion criteria and were selected. Results: The ranking of relative efficacy compared with placebo in descending order was Q-switched Nd:Yag 1,064-nm laser (QSND), intense pulsed light, ablative fractional laser (AFL), triple combined cream (TCC), topical vitamin C, oral tranexamic acid (oTA), peeling, azelaic acid, microneedles (MNs), topical tranexamic acid (tTA), tretinoin, picosecond laser, hydroquinone (HQ), and non-AFL. Moreover, QSND was more effective than HQ and tTA against melasma. The ranking of percentage (%) of side effects in ascending order for each of 14 therapies with more than 80 participants was tretinoin (10.1%), oTA (17.6%), HQ (18.2%), AFL (20.0%), QSND (21.5%), TCC (25.7%), tTA (36.75%), peeling (38.0%), and MN (52.3%). Taking both efficacy and safety into consideration, TCC was found to be the most favorable selection among the topical drugs for melasma. QSND and AFL were still the best ways to treat melasma among photoelectric devices. oTA as system administration was a promising way recommended for melasma. Among 31 studies, 87% (27/31) studies showed that the efficacy of combination therapies is superior to that of single therapy. The quality of evidence in this study was generally high because of nearly 50% of split-face RCTs. Conclusions: Based on the published studies, this NMA indicated that QSND, AFL, TCC, and oTA would be the preferred ways to treat melasma for dermatologists. However, more attention should be paid to the efficacy and safety simultaneously during the clinical application. Most of the results were in line with those of the previous studies, but a large number of RCTs should be included for validation or update. Systematic Review Registration: identifier: CRD42021239203.

SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) prevents cardiac remodeling after myocardial infarction through ERK/SMAD signaling pathway.

In this study, we aimed to investigate the role of SH2 domain-containing protein tyrosine phosphatase-2 (SHP-2) in cardiac remodeling after myocardial infarction (MI) and explore the underlying molecular mechanism. MI model was established by ligation of the left anterior descending coronary artery. C57/BL6J mice were randomly administered with 3.0 mg/kg/day PHPS1 (PHPS1-treated group) or normal saline (model group) by intraperitoneal injection. After 4 weeks of infusion, the effects of PHPS1 on cardiac remodeling were evaluated. Echocardiography results showed that PHPS1 treatment aggravated the MI-induced deterioration of cardiac function, with worse cardiac function parameters. PHPS1 treatment significantly increased the infarcted area, as well as the fibrotic area and the expression of collagen I and collagen III. Western blots and immunofluorescence staining showed that PHPS1 treatment up-regulated the expression of p-GRK2, p-SMAD2/3 and p-ERK1/2, while U0126 reversed the effect of PHPS1. The present study indicated that PHPS1 treatment contributed to myocardial fibrosis and infarction by activating ERK/SMAD signaling pathway, suggesting that SHP-2 may be a promising treatment target for cardiac remodeling after MI.

High-Performance Photoinduced Memory with Ultrafast Charge Transfer Based on MoS2 /SWCNTs Network Van Der Waals Heterostructure.

Photoinduced memory devices with fast program/erase operations are crucial for modern communication technology, especially for high-throughput data storage and transfer. Although some photoinduced memories based on 2D materials have already demonstrated desirable performance, the program/erase speed is still limited to hundreds of micro-seconds. A high-speed photoinduced memory based on MoS2 /single-walled carbon nanotubes (SWCNTs) network mixed-dimensional van der Waals heterostructure is demonstrated here. An intrinsic ultrafast charge transfer occurs at the heterostructure interface between MoS2 and SWCNTs (below 50 fs), therefore enabling a record program/erase speed of ≈32/0.4 ms, which is faster than that of the previous reports. Furthermore, benefiting from the unique device structure and material properties, while achieving high-speed program/erase operation, the device can simultaneously obtain high program/erase ratio (≈106 ), appropriate storage time (≈103  s), record-breaking detectivity (≈1016  Jones) and multibit storage capacity with a simple program/erase operation. It even has a potential application as a flexible optoelectronic device. Therefore, the designed concept here opens an avenue for high-throughput fast data communications.

Performance enhancement of carbon nanotube thin film transistor by yttrium oxide capping.

Carbon nanotube thin film transistors (CNT-TFTs) are regarded as promising technology for active matrix pixel driving circuits of future flat panel displays (FPD). For FPD application, unipolar thin film transistors (TFTs) with high mobility (µ), high on-state current (ION), low off-current (IOFF) at high source/drain bias and small hysteresis are required simultaneously. Though excellent values of those performance metrics have been realized individually in different reports, the overall performance of previously reported CNT-TFTs has not met the above requirements. In this paper, we found that yttrium oxide (Y2O3) capping is helpful in improving both ION and µ of CNT-TFTs. Combining Y2O3 capping and Al2O3 passivation, unipolar CNT-TFTs with high ION/IOFF (>107) and low IOFF (∼pA) at -10.1 V source/drain bias, and relatively small hysteresis in the range of -30 V to +30 V gate voltage were achieved, which are capable of active matrix display driving.

Ultraviolet/ozone and oxygen plasma treatments for improving the contact of carbon nanotube thin film transistors.

Carbon nanotube thin film transistor (CNT-TFT) is an emerging technology for future macroelectronics, such as chemical and biological sensors, optical detectors, and the backplane driving circuits for flat panel displays. The mostly reported fabrication method of CNT-TFT is a lift-off based photolithography process. In such fabrication process, photoresist (PR) residue contaminates the interface of tube-metal contact and deteriorates the device performance. In this paper, ultraviolet ozone (UVO) and oxygen plasma treatments were employed to remove the PR contamination. Through our well-designed experiments, the UVO treatment is confirmed an effective way of cleaning contamination at the tube-metal interface, while oxygen plasma treatment is too reactive and hard to control, which is not appropriate for CNT-TFTs. It is determined that 2-6 min UVO treatment is the preferred window, and the best optimized treatment time is 4 min, which leads to 15% enhancement of device performance.

A sacrificial layer strategy for photolithography on highly hydrophobic surface and its application for electrowetting devices.

Patterning micro-structures on highly hydrophobic surface by photolithography is usually inevitable for fabricating devices based on electrowetting effects. The key challenges for such photolithography processes are how to coat photoresist uniformly and maintain the hydrophobicity of the highly hydrophobic surface, which are usually two contradict aspects. Moreover, the patterned microstructure must adhere to the highly hydrophobic surface excellently, which is critical for device application. However, a simple and robust fabrication process that fulfills all the above requirements was seldom reported. In this paper, we developed a sacrificial layer photolithography strategy on highly hydrophobic surface. Photoresist is easily coated uniformly all over the substrate by introducing a sacrificial layer between the photoresist and the highly hydrophobic surface. The hydrophobicity of the exposed hydrophobic surface was maintained and the adhesion of the microstructures to the substrate is excellent. An electrowetting display sample was demonstrated by this fabrication strategy, which showed dynamic image displaying with response time less than 40 ms. The strategy is applicable to both rigid and flexible substrate and manufacturing compatible. We believe our developed photolithography process is important for research and development of devices based on electrowetting effect.

Carbon nanotube thin film transistors fabricated by an etching based manufacturing compatible process.

Carbon nanotube thin film transistors (CNT-TFTs) have been regarded as strong competitors to currently commercialized TFT technologies. Though much progress has been achieved recently, CNT-TFT research is still in the stage of laboratory research. One critical challenge for commercializing CNT-TFT technology is that the commonly used device fabrication method is a lift-off based process, which is not suitable for mass production. In this paper, we report an etching based fabrication process for CNT-TFTs, which is fully manufacturing compatible. In our process, the CNT thin film channel was patterned by dry etching, while wet etching was used for patterning the layers of metal and insulator. The CNT-TFTs were successfully fabricated on a 4 inch wafer in both top-gate and buried-gate geometries with low Schottky barrier contact and pretty uniform performance. High output current (>1.2 µA µm-1), high on/off current ratio (>105) and high mobility (>30 cm2 V-1 s-1) were obtained. Though the fabrication process still needs to be optimized, we believe our research on the etching fabrication process pushes CNT-TFT technology a step forward towards real applications in the near future.

Metal Induced Growth of Transition Metal Dichalcogenides at Controlled Locations.

Metal induced nucleation is adopted to achieve the growth of transition metal dichalcogenides at controlled locations. Ordered arrays of MoS2 and WS2 have successfully been fabricated on SiO2 substrates by using the patterned Pt/Ti dots as the nucleation sites. Uniform MoS2 monolayers with the adjustable size up to 50 µm are grown surrounding these metal patterns and the mobility of such layer is about 0.86 cm2/V·s. The crystalline flakes of WS2 are also fabricated extending from the metal patterns and the electron mobility of these flakes is up to 11.36 cm2/V·s.