Controlled Doping Methods for Radial p/n Junctions in Silicon

P/n and n/p junctions with depths of 200 nm to several micrometers have been created in flat silicon substrates as well as on 3D microstructures by means of a variety of methods, including solid source dotation (SSD), low-pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition, and plasma-enhanced chemical vapor deposition. Radial junctions in Si micropillars are inspected by optical and scanning electron micro­scopies, using a CrO3-based staining solution, which enables visualization of the junction depth. When applying identical-doping parameters to flat substrates, ball grooving, followed by staining and optical microscopy, yields similar junction depth values as high-resolution scanning electron microscopy imaging on stained cross-sections and secondary ion mass spectrometry depth profilometry. For the investigated 3D microstructures, doping based on SSD and LPCVD give uniform and conformal junctions. Junctions made with SSD-boron doping and CVD-phosphorus doping could be accurately predicted with a model based on Fick's diffusion law. 3D-microstructured silicon pillar arrays show an increased efficiency for sunlight capturing. The functionality of micropillar arrays with radial junctions is evidenced by improved short-circuit current densities and photovoltaic efficiencies compared with flat surfaces, for both n- and p-type wafers (average pillar arrays efficiencies of 9.4% and 11%, respectively, compared with 8.3% and 6.4% for the flat samples)

Ag2S deposited on oxidized polypropylene as composite material for solar light absorption

Thin film metal chalcogenides are superior solar light absorbers and can be combined into a functional material when deposited on polymeric substrates. Ag2S composite materials were synthesized on oxidized polypropylene using chemical bath deposition method and their properties were explored using XRD, XPS, AFM and UV–Vis. Polypropylene surfaces were modified using solution methods to introduce hydrophilicity via carboxylic group formation which resulted in Ag2S film deposition and adhesion. These films showed slightly sulfur enriched composition from XPS analysis with the sulfate-like species forming, presumably at the oxidized polymer surface sites. Ag2S particle growth mechanism included nucleation and rather large (few μm) aggregate formation eventually covering the complete polymer surface, as inferred from AFM analysis. Absorption edge of the composite material shifted toward the higher wavelength in UV–Vis spectrum with the number of Ag2S exposure times showing a decreasing bandgap and the possibility of obtaining tunable optical property Ag2S–polymer composites using CBD method

Yellow persistent luminescence of Sr2SiO4:Eu2+,Dy3+

This paperreportsthephotoluminescenceandafterglowofSr2SiO4 doped withEu2þ and Dy3þ. Factors governingtheformationofthemonoclinicororthorhombicphaseofthisortho-silicatearedescribed and theimpactofthecrystallographicmodificationontheluminescenceandafterglowunderUVand VUV excitationarediscussedandinsightinfactorslimitingtheefficiencyofthisyellowafterglow materialisgiven

Yellow persistent luminescence of Sr2SiO4:Eu2+,Dy3+

This paperreportsthephotoluminescenceandafterglowofSr2SiO4 doped withEu2þ and Dy3þ. Factors governingtheformationofthemonoclinicororthorhombicphaseofthisortho-silicatearedescribed and theimpactofthecrystallographicmodificationontheluminescenceandafterglowunderUVand VUV excitationarediscussedandinsightinfactorslimitingtheefficiencyofthisyellowafterglow materialisgiven

Electrochemical CO2 reduction on Cu2O-derived copper nanoparticles: Controlling the catalytic selectivity of hydrocarbons

The catalytic activity and hydrocarbon selectivity in electrochemical carbon dioxide (CO2) reduction on cuprous oxide (Cu2O) derived copper nanoparticles is discussed. Cuprous oxide films with [100], [110] and [111] orientation and variable thickness were electrodeposited by reduction of copper(II) lactate on commercially available copper plates. After initiation of the electrochemical CO2 reduction by these oxide structures, the selectivity of the process was found to largely depend on the parent Cu2O film thickness, rather than on the initial crystal orientation. Starting with thin Cu2O films, besides CO and hydrogen, selective formation of ethylene is observed with very high ethylene-to-methane ratios (8 to 12). In addition to these products, thicker Cu2O films yield a remarkably large amount of ethane. Long term Faradaic efficiency analysis of hydrocarbons shows no sign of deactivation of the electrodes after 5 hours of continuous experiment. Online mass spectroscopy studies combined with X-ray diffraction data suggest the reduction of the Cu2O films in the presence of CO2, generating a nanoparticulate Cu morphology, prior to the production of hydrogen, CO, and hydrocarbons. Optimizing coverage, number density and size of the copper nanoparticles, as well as local surface pH, may allow highly selective formation of the industrially important product ethylen

A Study on the Technical Efficiency of Taiwan Biopharmaceutical Firms with Application of DEA and Malmquist Productivity Index

本文旨在實證當前台灣生技新藥產業廠商之技術效率、廠商之社經背景對其效率值之影響，與研究「生技新藥產業發展條例」施行前後生技新藥廠商之跨年度效率值表現情形。利用2007年7月4日至2009年2月3日止已申請通過「生技新藥產業發展條例」之13家生技新藥公司資料進行二階段資料包絡分析法 (Two – Stage DEA) 與Malmquist生產力指數 (Malmquist Productivity Index) 兩種方法之研究分析。 首先觀察相關研究與生技新藥產業特性分別設定四個投入變數 - 「員工總人數」、「研發支出」、「研發人員碩士以上學歷之比例」與「研發年數」；三個產出項目 - 「年度營業額」與「公司擁有之專利數」；與五個環境影響因素 - 「公開發行」、「廠商位置」、「創辦人背景」、「人類藥物」與「政府計畫補助」，以2007年樣本資料來進行二階段DEA技術效率分析，進而再以Malmquist生產力指數來分析生技新藥廠商之跨年度效率變動情形。 本文以二階段DEA實證所得之技術效率做為主要比較基礎，由結果發現樣本廠商技術效率介0.109~1.000之間，共5家技術效率值為1。此外，第二階段DEA中發現，設址於科學園區或是選擇研發人類藥物，將會對廠商的技術效率值產生負向的影響。相對地，若生技新藥廠商有獲得政府小型企業創新研發計畫（SBIR）補助，對於技術效率則有正面的助益。二階段DEA實證結果進而可歸納出以下之結論: 1.13個樣本生技新藥廠商中以研發「植物用藥」的公司在技術效率 上表現最佳，其次依序為「慢性病藥物」廠商、「癌症藥物」廠 商與「其他人類用藥物」廠商。 2.以DEA衡量樣本廠商現階段之規模報酬屬性，發現屬於固定規模報 酬者有8家 (占62%)；遞增規模報酬廠商有5家 (占38 %)。而樣本 廠商中並無存在規模報酬遞減者。 3.整體而言，具有以下特性之生技新藥廠商技術效率表現較佳： （1）設廠於非科學園區；（2）研發「非人類藥物」；（3）申請 通過政府小型企業創新研發計畫補助。 此外，針對6家生技新藥廠商之Malmquist生產力指數分析結果顯示，「生技新藥產業發展條例」實施後除了研發「植物用藥」之廠商生產力呈現進步外，「人類癌症藥物」與「人類慢性病藥物」廠商生產力變動都呈現衰退。This study examined the technical efficiency (TE) of Taiwan's biopharmaceutical firms, gauged the impact of the environmental factors to firms' efficiency, and investigated the biopharmaceutical firms' efficiency performance after “Statute for Biopharmaceutical Industry Development, SBID” practiced since July 2007. The “Two - Stage DEA” and “Malmquist Productivity Index”methods were applied to estimate the data of 13 biopharmaceutical firms who had certificated by SBID prior to the 3rd /February/2009. First, the related thesises and the characteristic of biopharmaceutical industry were observed to set up “four inputs”, the total number of employees, R & D expenditures, the ratio of master''s degree or higher in R & D department, and R & D duration, “two outputs”, annual turnover and the number of patents, and “five environmental factors”, IPO, location, founder background, human medicine, and government R&D support, to proceed two stage DEA and Malmquist productivity index. TE was used as a benchmark for comparing efficiency in this study. From the result, biopharmaceutical firms' TEs were between 0.109 and 1.000. Within 13 sample firms, 5 biopharmaceutical firms' TEs were “1”. Moreover, the research argued that the biopharmaceutical firm who located in science parks or researched human medicine tended to have worse TE. On the contrary, biopharmaceutical firms which received government subsidy were likely to have better TE.The following conclusion could be drawn from the two stage DEA analysis: 1.“Plant used medicine firm” had the most outstanding performance in technical efficiency, and it was followed by “chronic disease medicine firm”, “cancer medicine firm” and “other human medicine firm”. 2.When estimating the RTS, there were 8 sample firms in the CRS stage, accounting for 62%, and 5 sample firms in the IRS stage, making up 38%. There were no sample firms in the DRS stage. 3.In general, the biopharmaceutical firms having following characteristics exhibited better TE: (1) located in non- science park areas; (2) researched non-human medicine; (3) received government SBIR subsidy. According to Malmquist productivity index estimation, only “plant used medicine” firm's productivity trend displayed increase after SBID bought into practice. On the other hand, “chronic disease medicine” firms and“cancer medicine” firms' productivity trend displayed decrease.第一章 緒論…………………………………………………1 第一節 研究背景……………………………………………1 第二節 研究動機與目的……………………………………3 第三節 研究方法與流程……………………………………5 第四節 資料來源……………………………………………6 第二章 我國生技新藥產業之現況…………………………8 第一節 生技新藥之定義、發展歷史與特性………………8 第二節 生技製藥產業發展現況……………………………17 第三節 我國推動生技新藥產業之政策……………………25 第四節 綜合結語……………………………………………27 第三章 文獻回顧……………………………………………29 第一節 生技產業之效率……………………………………29 第二節 資料包絡分析法……………………………………32 第三節 Malmquist生產力指數分析法…………………… 35 第四節 政府鼓勵研發之政策效果…………………………36 第四章 理論基礎與研究方法………………………………39 第一節 效率之基本概念……………………………………39 第二節 評估效率方法………………………………………40 第三節 資料包絡分析法概念………………………………44 第四節 二階段DEA………………………………………… 50 第五節 跨期效率變動 － Malmquist生產力指數……… 52 第六節 本章小結……………………………………………53 第五章 問卷設計與調查……………………………………54 第一節 問卷設計……………………………………………54 第二節 調查方式……………………………………………57 第三節 樣本之特性…………………………………………58 第六章 實證推估與分析……………………………………63 第一節 變數設定……………………………………………63 第二節 生產效率的實證分析………………………………66 第七章 結論與建議…………………………………………80 第一節 結論…………………………………………………80 第二節 建議…………………………………………………85 第三節 研究限制與未來研究方向…………………………88 參考文獻 ………………………………………………… 90 附錄一 ………………………………………………… 97 附錄二 ………………………………………………… 10