Transparent electronics is today one of the most advanced topics for a wide range of device applications. The key components are wide bandgap semiconductors, where oxides of different origins play an important role, not only as passive component but also as active component, similar to what is observed in conventional semiconductors like silicon. Transparent electronics has gained special attention during the last few years and is today established as one of the most promising technologies for leading the next generation of flat panel display due to its excellent electronic performance. In this paper the recent progress in n- and p-type oxide based thin-film transistors (TFT) is reviewed, with special emphasis on solution-processed and p-type, and the major milestones already achieved with this emerging and very promising technology are summarizeed. After a short introduction where the main advantages of these semiconductors are presented, as well as the industry expectations, the beautiful history of TFTs is revisited, including the main landmarks in the last 80 years, finishing by referring to some papers that have played an important role in shaping transparent electronics. Then, an overview is presented of state of the art n-type TFTs processed by physical vapour deposition methods, and finally one of the most exciting, promising, and low cost but powerful technologies is discussed: solution-processed oxide TFTs. Moreover, a more detailed focus analysis will be given concerning p-type oxide TFTs, mainly centred on two of the most promising semiconductor candidates: copper oxide and tin oxide. The most recent data related to the production of complementary metal oxide semiconductor (CMOS) devices based on n- and p-type oxide TFT is also be presented. The last topic of this review is devoted to some emerging applications, finalizing with the main conclusions. Related work that originated at CENIMAT|I3N during the last six years is included in more detail, which has led to the fabrication of high performance n- and p-type oxide transistors as well as the fabrication of CMOS devices with and on paper.

Oxide Semiconductor Thin‐Film Transistors: A Review of Recent Advances

Electron and ambipolar transport in organic field-effect transistors.

Biocompatibility, Pharmaceutical and Biomedical Applications L. Harivardhan Reddy,†,‡ Jose ́ L. Arias, Julien Nicolas,† and Patrick Couvreur*,† †Laboratoire de Physico-Chimie, Pharmacotechnie et Biopharmacie, Universite ́ Paris-Sud XI, UMR CNRS 8612, Faculte ́ de Pharmacie, IFR 141, 5 rue Jean-Baptiste Cleḿent, F-92296 Chat̂enay-Malabry, France Departamento de Farmacia y Tecnología Farmaceútica, Facultad de Farmacia, Campus Universitario de Cartuja s/n, Universidad de Granada, 18071 Granada, Spain ‡Pharmaceutical Sciences Department, Sanofi, 13 Quai Jules Guesdes, F-94403 Vitry-sur-Seine, France

Magnetic nanoparticles: design and characterization, toxicity and biocompatibility, pharmaceutical and biomedical applications.

This Review focuses on recent developments in the use of ZnO nanostructures for dye-sensitized solar cell (DSC) applications. It is shown that carefully designed and fabricated nanostructured ZnO films are advantageous for use as a DSC photoelectrode as they offer larger surface areas than bulk film material, direct electron pathways, or effective light-scattering centers, and, when combined with TiO2, produce a core–shell structure that reduces the combination rate. The limitations of ZnO-based DSCs are also discussed and several possible methods are proposed so as to expand the knowledge of ZnO to TiO2, motivating further improvement in the power-conversion efficiency of DSCs.

https://depts.washington.edu/solgel/documents/pub_docs/journal_docs/2009/advanced_material2009.pdf

ZnO Nanostructures for Dye-Sensitized Solar Cells

We report high-performance ZnO thin-film transistor (ZnO-TFT) fabricated by rf magnetron sputtering at room temperature with a bottom gate configuration. The ZnO-TFT operates in the enhancement mode with a threshold voltage of 19V, a saturation mobility of 27cm2∕Vs, a gate voltage swing of 1.39V∕decade and an on/off ratio of 3×105. The ZnO-TFT presents an average optical transmission (including the glass substrate) of 80% in the visible part of the spectrum. The combination of transparency, high mobility, and room-temperature processing makes the ZnO-TFT a very promising low-cost optoelectronic device for the next generation of invisible and flexible electronics.

Wide-bandgap high-mobility ZnO thin-film transistors produced at room temperature

Purpose: Capecitabine (Xeloda) is a new orally administered fluoropyrimidine carbamate that was rationally designed to exert its effect by tumor-selective activation. We attempted to evaluate the efficacy and toxicity of preoperative chemoradiation using capecitabine in locally advanced rectal cancer. Methods and Materials: Between July 1999 and March 2001, 45 patients with locally advanced rectal cancer (cT3/T4 or N+) were treated with preoperative chemoradiation. Radiation of 45 Gy/25 fractions was delivered to the pelvis, followed by a 5.4 Gy/3 fractions boost to the primary tumor. Chemotherapy was administered concurrent with radiotherapy and consisted of 2 cycles of 14-day oral capecitabine (1650 mg/m 2 /day) and leucovorin (20 mg/m 2 /day), each of which was followed by a 7-day rest period. Surgery was performed 6 weeks after the completion of chemoradiation. Results: Thirty-eight patients received definitive surgery. Primary tumor and node downstaging occurred in 63% and 90% of patients, respectively. The overall downstaging rate, including both primary tumor and nodes, was 84%. A pathologic complete response was achieved in 31% of patients. Twenty-one patients had tumors located initially 5 cm or less from the anal verge; among the 18 treated with surgery, 72% received sphincter-preserving surgery. No Grade 3 or 4 hematologic toxicities developed. Other Grade 3 toxicities were as follows: hand-foot syndrome (7%), fatigue (4%), diarrhea (4%), and radiation dermatitis (2%). Conclusion: These preliminary results suggest that preoperative chemoradiation with capecitabine is a safe, well-tolerated, and effective neoadjuvant treatment modality for locally advanced rectal cancer. In addition, this preoperative treatment has a considerable downstaging effect on the tumor and can increase the possibility of sphincter preservation in distal rectal cancer.

Preoperative chemoradiation using oral capecitabine in locally advanced rectal cancer

We report on the photodetecting properties of a ZnO-based thin-film transistor (TFT) that has been fabricated on a SiO2/p-Si substrate by rf magnetron sputtering at room temperature. Our ZnO-based TFT exhibited a saturation current level of about 6.5 μA under a gate bias of 40 V, decent electron mobility of 0.1 cm2/V s, and on/off current ratio of ∼106 in the dark. Illuminated by ultraviolet (λ=340 nm), blue (λ=450 nm), and green (λ=540 nm) light with intensity of 0.7 mW/cm2, our TFT displays high photocurrent gain of 50, 32, and 15 μA, respectively, under a gate bias of 40 V. In the channel depletion state with gate bias of −30 V, the photodetecting sensitivity becomes much higher than in the accumulation state. It is thus concluded that our ZnO-based TFT can be a good UV photodetecting device as well as an electronic device.

Photodetecting properties of ZnO-based thin-film transistors

We report on the fabrication of pentacene thin-film transistors (TFTs) with Al2O3+x films as the gate dielectric that has been deposited on indium-tin-oxide glass by rf magnetron sputtering at room temperature. Although the Al2O3+x was expected to show lower capacitance and breakdown field than stoichiometric Al2O3, our pentacene TFTs with optimized thin Al2O3+x gate dielectric exhibited a moderately high field mobility of 0.14 cm2/V s, an outstanding subthreshold slope of 0.88 V/dec, and an on/off ratio over 106. Our work demonstrates that RT-deposited Al2O3+x is a promising gate dielectric material for organic TFTs.

Pentacene thin-film transistors with Al2O3+x gate dielectric films deposited on indium-tin-oxide glass

Purpose: To examine retrospectively whether levels of epidermal growth factor receptor (EGFR) expression can predict tumor downstaging after preoperative chemoradiotherapy in patients with locally advanced rectal cancer. Methods and Materials: A total of 183 patients with rectal cancer (cT3-T4 or N+) were enrolled in this study. Preoperative chemoradiotherapy consisted of 50.4 Gy of pelvic radiation with concurrent 5-fluorouracil and leucovorin bolus intravenous chemotherapy in 94 patients or oral capecitabine and leucovorin in 89 patients. EGFR expression in pretreatment paraffin-embedded tumor biopsy specimens was assessed by immunohistochemistry. EGFR expression was determined from the intensity and extent of staining. Tumor downstaging was defined as a reduction of at least one T-stage level. Results: Tumor downstaging occurred in 97 patients (53%), and the tumors showed a pathologic complete response in 27 patients (15%). Positive EGFR expression was observed in 140 (76%) of 183 patients. EGFR expression levels were low in 113 patients (62%) and high in 70 patients (38%). On logistic regression analysis, the significant predictive factor for increased tumor downstaging was a low level of EGFR expression and preoperative chemotherapy using oral capecitabine (odds ratio, 0.437; p = 0.012 vs. odds ratio, 3.235; p Conclusion: A high level of EGFR expression may be a significant predictive molecular marker for decreased tumor downstaging after preoperative chemoradiotherapy in locally advanced rectal cancer.

Epidermal growth factor receptor as a predictor of tumor downstaging in locally advanced rectal cancer patients treated with preoperative chemoradiotherapy.

The cell wall skeleton of Mycobacterium bovis Bacillus Calmette-Guerin (BCG/CWS) is an effective antitumor immunotherapy agent. Here, we demonstrate that BCG/CWS has a radiosensitizing effect on colon cancer cells through the induction of autophagic cell death. Exposure of HCT116 colon cancer cells to BCG/CWS before ionizing radiation (IR) resulted in increased cell death in a caspase-independent manner. Treatment with BCG/CWS plus IR resulted in the induction of autophagy in colon cancer cells. Either the autophagy inhibitor 3-methyladenine or knockdown of beclin 1 or Atg7 significantly reduced tumor cell death induced by BCG/CWS plus IR, whereas the caspase inhibitor z-VAD-fmk failed to do so. BCG/CWS plus IR-mediated autophagy and cell death was mediated predominantly by the generation of reactive oxygen species (ROS). The c-Jun NH(2)-terminal kinase pathway functioned upstream of ROS generation in the induction of autophagy and cell death in HCT116 cells after co-treatment with BCG/CWS and IR. Furthermore, toll-like receptor (TLR) 2, and in part, TLR4, were responsible for BCG/CWS-induced radiosensitization. In vivo studies revealed that BCG/CWS-mediated radiosensitization of HCT116 xenograft growth is accompanied predominantly by autophagy. Our data suggest that BCG/CWS in combination with IR is a promising therapeutic strategy for enhancing radiation therapy in colon cancer cells through the induction of autophagy.

Jun-Sang Kim

Papers

Preoperative chemoradiation using oral capecitabine in locally advanced rectal cancer

Photodetecting properties of ZnO-based thin-film transistors

Pentacene thin-film transistors with Al2O3+x gate dielectric films deposited on indium-tin-oxide glass

Epidermal growth factor receptor as a predictor of tumor downstaging in locally advanced rectal cancer patients treated with preoperative chemoradiotherapy.

Bacillus calmette-guerin cell wall cytoskeleton enhances colon cancer radiosensitivity through autophagy.