Name: fabrication of high contrast gratings for the spectrum splitting dispersive element in a concentrated photovoltaic system
Uploaded: 2015-07-18T14:00:00.000+00:00
Duration: 12 min 8 s
Description: Watch this Scientific Journal Video about Fabrication of High Contrast Gratings for the Spectrum Splitting Dispersive Element in a Concentrated Photovoltaic System at JoVE.com

この研究は、米国エネルギー省によって資金を供給エネルギーナノサイエンス、エネルギーフロンティア研究センターセンター、受賞番号DE-SC0001013下科学局の一部としてサポートされていました。また、TiO 2の膜スパッタリングおよび屈折率測定への彼らの助けのために博士マックス·チャンとHP研究所の博士建華ヤンに感謝したいと思います。

1.ナノインプリントモールド用のブランクポリジメチルシロキサン（PDMS）基板を準備します<ol><li>シリコンウェーハ処理プロセス<ol><li>アセトン、メタノール、イソプロパノールですすぐことによって、4インチのシリコンウエハを清掃してください。 </li><li>それは窒素ガンを用いてブロー乾燥。 </li><li> 15分間の内部に浸漬することにより：（30％過酸化水素水と硫酸の1混合物3）ピラニア溶液を使用して清掃してください。 </li><li> DI水でそれを洗浄します。窒素ガンを用いたドライ吹きます。 </li><li>ガラスデシケーター中でウエハを配置します。デシケーター中に薬剤（トリクロロシラン）を放出するドロップ（20滴= 1ミリリットル）を追加します。 </li><li>ゲージは-762トルを読み取るまでデシケーターをポンプダウンし、5時間を待ちます。 </li><li>離型剤で処理されたウェハアウトを取ります。 </li></ol></li><li> PDMSフィルムの作製（ナノインプリントにおけるモールドとして使用されます） <ol><li>シリコーンエラストマーベース10gと硬化剤1gを秤量します。 </li><li>同一のガラスビーカーにそれらを追加します。 </li><li> STI5分間、ガラス棒でrと混ぜます。 </li><li>ゲージはすべて捕捉された気泡を送り出すために-762トルを読み取るまで、真空デシケーターに混合物を入れてください。 </li><li>処理した4インチのシリコンウェーハ上に均等に広げます。 </li><li> PDMS膜を硬化させるために80℃で7時間、真空オーブン中で上にPDMSを有するウェーハを焼きます。 </li></ol></li></ol> 2.ナノインプリントモールド（マスターモールドから複製）を準備<ol><li> 1,500rpmで30秒間清浄なブランクシリコンウェハ上に硬化性レジストをUVの12滴（20滴= 1ml）中（15.2％）をスピン。 </li><li>慎重に処理されたシリコンウェハオフPDMS膜の一部を剥離。 </li><li>硬化性レジストUV上にPDMSフィルムを入れて、それが紫外線を5分間耐えることをはがし吸収しましょう​​。 </li><li> 2回同じPDMS膜上に2.1〜2.3を繰り返します。それぞれ3分、1分間耐えるUVを吸収します。 </li><li> （3回の紫外線吸収に抵抗した後）は、シリコンマスターモールドにPDMSフィルムを配置します。 </li><li>窒素環境と室内に入れて。 </li><li> 5分間のサンプルを硬化させるためにUVランプをオンにします。 </li><li> PDMSフィルムをはがし。 UV硬化PDMS上のレジストは、マスター型のネガパターンを維持します。 </li><li> PDMSモールドを治療するためのRF O 2プラズマを使用してください。 （RFパワー：30 W、圧力：260トール、時間：1分） </li><li> 2時間離型剤の一滴（20滴= 1ml）で真空チャンバ内のPDMSモールドを配置します。 </li></ol> 3.ナノインプリントパターン転写<ol><li> 3,500 rpmで50秒間、インプリントされる基板上にPMMA（996k、3.1％）、8滴（20滴= 1 ml）をスピン。 </li><li> 120℃で5分間、ホットプレート上で焼きます。 </li><li>試料が冷却するのを待ちます。 </li><li> UV硬化性の8滴（20滴= 1 ml）を同一基板上にスピン（3.9％）をレジスト</li><li>サンプル（UVの両方でレジストPMMA）上にPDMSモールド（ステップ2で調製）を配置します。 </li><li>窒素環境と室内に入れて。</li><li> 5分間硬化させるためにUVランプをオンにします。 </li><li>ピールサンプルオフPDMSモールドとPDMSモールド上のパターンを試料に転送されます。 </li></ol> 4.クロムリフトオフプロセス<ol><li> UVの残留層を反応性イオンエッチングレジストおよびPMMA 注：ICPマシンのSOPはhttps://www.nanocenter.umd.edu/equipment/fablab/sops/etch-07/Oxford%20Chlorine%20Etcher%20SOP.pdfで見つけることができます<ol><li> RIE、ICPマシンにログインします。 </li><li>空白の4インチのシリコンウェーハをロードします。 10分間きれいなレシピを実行します。 </li><li>ブランクシリコンウエハを取り出してください。 </li><li>別の清浄なシリコンウェハ上にサンプルをマウントし、マシンにロードします。 </li><li> 2分間のエッチングレシピをレジストUVを実行します（レシピは、表1に見ることができます）。 </li><li>サンプルを取り出します。空白の4インチのシリコンウェーハをロードします。再実行しクリーンなレシピを10分間（ 表1を参照のこと）。 </li><li>清浄なシリコンウェハ上にサンプルをマウントしますマシンにロードします。 </li><li> 2分間（ 表1に見ることができる）、PMMAのエッチングレシピを実行します。 注：ここでの残留がエッチングされたレジストを基板が露出しています。 </li></ol></li><li> Crの電子ビーム蒸着<ol><li>電子ビーム蒸発器にログインします。 </li><li>チャンバー内にCr金属源とサンプルをロードします。 </li><li>厚さ（20 nm）を蒸着速度（0.03 nmの/秒）を設定します。 </li><li>必要な真空（10 -7トル）が到達するまで、チャンバポンプ。 </li><li>堆積プロセスを開始します。 </li><li>成膜終了後の試料を取り出します。 </li></ol></li><li> CRリフトオフ手順<ol><li> 5分間の超音波撹拌しながらアセトン中に試料を浸し。 </li><li>アセトン、メタノール、イソプロパノールでリンスすることにより、サンプルを清掃してください。 注：Crはレジストのリフトオフされ、基板エッチングのためのCrマスクを形成する上で蒸発させました。 </li></ol></li></ol> 5.のTiO 2発osition <ol><li>ロードサンプル。 </li><li>直流マグネトロンスパッタリングマシンのパラメータを設定します<ol><li> 1.5ミリトールのチャンバ圧力、100sccmのアルゴンの流れと130 Wのスパッタ電力を使用して</li><li> 27℃の温度および20回転数のステージ回転速度を使用してください。 </li></ol></li><li>スパッタプロセスを開始し、所望の厚さで停止します。 </li><li>サンプルを取り出し、3時間300℃の酸素雰囲気中のTiO 2膜をアニール。 </li></ol> 6.ハイコントラストグレーティングエッチング<ol><li>誘導結合プラズマ（ICP）反応性イオンエッチング（RIE）マシンにログインします。 </li><li> TiO 2のエッチング<ol><li>ブランク4インチのシリコンウェーハをロードします。 </li><li> 10分間（ 表1に見ることができる）クリーンレシピを起動し、実行します。 </li><li>ブランクウエハをロードアンロードし、Crマスクでサンプルをロードします。 </li><li>エッチング時間を設定します。 TiO 2のエッチングレシピを開始します。エッチングプロセスが自動matically停止。 </li><li>サンプルをアンロードします。 </li></ol></li><li> SiO 2のエッチング<ol><li> SiO 2のエッチングレシピを使用する以外は手順を繰り返し5.2。 </li></ol></li></ol> 7.反射率測定<ol><li>ログインして、測定システムの電源をオンにします。 </li><li>試料ホルダーに、反射率標準ミラーを配置し、光路の位置を合わせます。 </li><li> 100％の反射率のためのシステムのキャリブレーション。 </li><li>反射率標準ミラーを外し、HCGを配置します。 </li><li> HCGの反射率を測定します。 </li><li>データを保存し、測定システムからログアウトします。 </li></ol>

<ol>
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The authors have nothing to disclose.

まず、TiO 2の膜の品質は、HCGのパフォーマンスのために非常に重要です。 TiO 2のフィルムが少ない損失と表面粗さを有する場合、反射率ピークが高くなります。光学モードの閉じ込めがHCGで平坦で広い反射バンドを生じさせることができ指数の高いコントラストによって強化されるため、より高い屈折率を有するTiO 2の膜も良好です。 第二に、製?...

現代社会は、再生可能なエネルギー源へのエネルギー消費量のかなりの部分を移動させずに生存しないであろう。これを実現するために、我々は近い将来、石油系エネルギー源よりも低コストで再生可能エネルギーを収穫する方法を見つける必要があります。太陽エネルギーは地球上で最も豊富な再生可能エネルギーです。進歩の多くは太陽エネルギーハーベスティングで行われていることにもかかわらず、石油系エネルギー源と競合することは非常に困難です。太陽電池の効率を改善することは、太陽エネルギーハーベスティングのシステムコストを低減するための最も効率的な方法の一つです。 それに高価なタンデム多接合太陽電池セル2を利用することが経済的に実行可能であるように光学レンズ及びディッシュ反射器は、通常、小面積の太陽電池に太陽光発電入射高濃度を達成するために最も集中太陽光発電（CPV）システム1で使用されていますCPVシステム、及び妥当性を維持します同時にコスト。それらは通常、より広い太陽スペクトル応答よりも高い全体的な変換効率を有するものの、通常、太陽電池の大面積の設置を必要とするほとんどの非濃縮太陽光発電システムのための、高コストのタンデム太陽電池は、組み込むことができません単接合太陽電池3。 近年、並列スペクトル分割光学系（ すなわち、分散素子）を利用して、並列スペクトル分割太陽光発電技術4により、類似またはより良好なスペクトル範囲と変換効率が高価タンデム型太陽電池を使用することなく達成できることになりました。太陽スペクトルの異なる帯域に分割することができ、それぞれのバンドが吸収され、特殊な単接合太陽電池によって電気に変換することができます。このように、CPVシステムで高価なタンデム型太陽電池は、単接合太陽電池の並列分布に置き換えることができますパフォーマンスに妥協することなく複数。 この報告書に設計された分散素子は、改善された太陽光電力変換効率およびコスト削減のための並列スペクトル分割を実現するために（ディッシュ反射に基づいて）反射CPVシステムに適用することができます。多層高コントラスト回折格子（HCG）5は、光バンドリフレクタとして機能するようにHCGの各層を設計することにより、分散素子として使用されます。分散素子の構造やパラメータが数値的に最適化されています。また、（TiO 2の）誘電スパッタリング、ナノインプリントリソグラフィ6と反応性イオンエッチングを使用して、分散素子のための高コントラスト回折格子の製造を検討し、実証されています。

<table><tbody><tr><td>184 Silcone elastomer kit</td><td>Sylgard</td><td></td><td>Polydimethylsiloxane (PDMS)</td></tr><tr><td>4 inch silicon wafer</td><td>Universitywafer</td><td></td><td></td></tr><tr><td>4 inch fused silica wafer</td><td>Universitywafer</td><td></td><td></td></tr><tr><td>Poly(methyl methacrylate)</td><td>Sigma-Aldrich</td><td>182265</td><td></td></tr><tr><td>UV-curable resist</td><td></td><td></td><td>Nor available on market</td></tr><tr><td>PlasmaLab System 100</td><td>Oxford Instruments</td><td></td><td>ICP IRE machine</td></tr><tr><td>UV curing system for nanoimprint fabrication</td><td></td><td></td><td>Not available on market</td></tr><tr><td>Ocean Optics HR-4000&amp;nbsp;</td><td>Ocean Optics</td><td>HR-4000</td><td>Spectrometer with normal detector</td></tr><tr><td>Lambda 950 UV / VIS</td><td>PerkinElmer</td><td></td><td>spectrometer with hemisphere intergration detector</td></tr><tr><td>JSM-7001F-LV</td><td>JEOL</td><td></td><td>Field emission SEM</td></tr><tr><td>DC magnetron sputtering machine</td><td></td><td></td><td>Equipment is in HP labs, who helped us to sputter the TiO&lt;sub&gt;2&lt;/sub&gt;</td></tr><tr><td>Metal e-beam evaporator</td><td>Temescal</td><td>BJD-1800</td><td></td></tr></tbody></table>

fabrication of high contrast gratings for the spectrum splitting dispersive element in a concentrated photovoltaic system

High contrast gratings are designed and fabricated and its application is proposed in a parallel spectrum splitting dispersive element that can improve the solar conversion efficiency of a concentrated photovoltaic system. The proposed system will also lower the solar cell cost in the concentrated photovoltaic system by replacing the expensive tandem solar cells with the cost-effective single junction solar cells. The structures and the parameters of high contrast gratings for the dispersive elements were numerically optimized. The large-area fabrication of high contrast gratings was experimentally demonstrated using nanoimprint lithography and dry etching. The quality of grating material and the performance of the fabricated device were both experimentally characterized. By analyzing the measurement results, the possible side effects from the fabrication processes are discussed and several methods that have the potential to improve the fabrication processes are proposed, which can help to increase the optical efficiency of the fabricated devices.

図1は、濃縮された太陽光発電システムにおける分散素子（回折格子多層高コントラスト（HCG））の実装を示しています。太陽の光は、第1の一次ミラーで反射され、ビームは反射し、異なる波長の異なる帯域に分割され、反射分散素子に入射されます。各バンドは電気への最高の吸収および変換のための太陽電池アレイ上の特定の場所に衝突します。このシステムの鍵は、HCGの?...

Watch this Scientific Journal Video about Fabrication of High Contrast Gratings for the Spectrum Splitting Dispersive Element in a Concentrated Photovoltaic System at JoVE.com

Fabrication of High Contrast Gratings for the Spectrum Splitting Dispersive Element in a Concentrated Photovoltaic System

The fabrication of high contrast gratings as the parallel spectrum splitting dispersive element in a concentrated photovoltaic system is demonstrated. Fabrication processes including nanoimprint lithography, TiO2 sputtering and reactive ion etching are described. Reflectance measurement results are used to characterize the optical performance.

集中太陽光発電システムにおけるスペクトル分割分散素子の高コントラスト回折格子の作製

High contrast gratings are designed and fabricated and its application is proposed in a parallel spectrum splitting dispersive element that can improve ...

fabrication-high-contrast-gratings-for-spectrum-splitting-dispersive

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

10.7K ビュー.  University of Sothern California. The fabrication of high contrast gratings as the parallel spectrum splitting dispersive element in a concentrated photovoltaic system is demonstrated. Fabrication processes including nanoimprint lithography, TiO2 sputtering and reactive ion etching are described. Reflectance measurement results are used to characterize the optical performance. 

ビデオ: Fabrication of High Contrast Gratings for the Spectrum Splitting Dispersive Element in a Concentrated Photovoltaic System

Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To compensate for lower light absorption such physically thin devices have to incorporate light-trapping which increases their optical thickness. Light scattering by textured surfaces is a common technique but it cannot be universally applied to all solar cell technologies. Some cells, for example those made of evaporated silicon, are planar as produced and they require an alternative light-trapping means suitable for planar devices. Metal nanoparticles formed on planar silicon cell surface and capable of light scattering due to surface plasmon resonance is an effective approach.
The paper presents a fabrication procedure of evaporated polycrystalline silicon solar cells with plasmonic light-trapping and demonstrates how the cell quantum efficiency improves due to presence of metal nanoparticles.
To fabricate the cells a film consisting of alternative boron and phosphorous doped silicon layers is deposited on glass substrate by electron beam evaporation. An Initially amorphous film is crystallised and electronic defects are mitigated by annealing and hydrogen passivation. Metal grid contacts are applied to the layers of opposite polarity to extract electricity generated by the cell. Typically, such a ~2 &mu;m thick cell has a short-circuit current density (Jsc) of 14-16 mA/cm2, which can be increased up to 17-18 mA/cm2 (~25% higher) after application of a simple diffuse back reflector made of a white paint.
To implement plasmonic light-trapping a silver nanoparticle array is formed on the metallised cell silicon surface. A precursor silver film is deposited on the cell by thermal evaporation and annealed at 23&deg;C to form silver nanoparticles. Nanoparticle size and coverage, which affect plasmonic light-scattering, can be tuned for enhanced cell performance by varying the precursor film thickness and its annealing conditions. An optimised nanoparticle array alone results in cell Jsc enhancement of about 28%, similar to the effect of the diffuse reflector. The photocurrent can be further increased by coating the nanoparticles by a low refractive index dielectric, like MgF2, and applying the diffused reflector. The complete plasmonic cell structure comprises the polycrystalline silicon film, a silver nanoparticle array, a layer of MgF2, and a diffuse reflector. The Jsc for such cell is 21-23 mA/cm2, up to 45% higher than Jsc of the original cell without light-trapping or ~25% higher than Jsc for the cell with the diffuse reflector only.
Introduction
Light-trapping in silicon solar cells is commonly achieved via light scattering at textured interfaces. Scattered light travels through a cell at oblique angles for a longer distance and when such angles exceed the critical angle at the cell interfaces the light is permanently trapped in the cell by total internal reflection (Animation 1: Light-trapping). Although this scheme works well for most solar cells, there are developing technologies where ultra-thin Si layers are produced planar (e.g. layer-transfer technologies and epitaxial c-Si layers) 1 and or when such layers are not compatible with textures substrates (e.g. evaporated silicon) 2. For such originally planar Si layer alternative light trapping approaches, such as diffuse white paint reflector 3, silicon plasma texturing 4 or high refractive index nanoparticle reflector 5 have been suggested.
Metal nanoparticles can effectively scatter incident light into a higher refractive index material, like silicon, due to the surface plasmon resonance effect 6. They also can be easily formed on the planar silicon cell surface thus offering a light-trapping approach alternative to texturing. For a nanoparticle located at the air-silicon interface the scattered light fraction coupled into silicon exceeds 95% and a large faction of that light is scattered at angles above critical providing nearly ideal light-trapping condition (Animation 2: Plasmons on NP). The resonance can be tuned to the wavelength region, which is most important for a particular cell material and design, by varying the nanoparticle average size, surface coverage and local dielectric environment 6,7. Theoretical design principles of plasmonic nanoparticle solar cells have been suggested 8. In practice, Ag nanoparticle array is an ideal light-trapping partner for poly-Si thin-film solar cells because most of these design principle are naturally met. The simplest way of forming nanoparticles by thermal annealing of a thin precursor Ag film results in a random array with a relatively wide size and shape distribution, which is particularly suitable for light-trapping because such an array has a wide resonance peak, covering the wavelength range of 700-900 nm, important for poly-Si solar cell performance. The nanoparticle array can only be located on the rear poly-Si cell surface thus avoiding destructive interference between incident and scattered light which occurs for front-located nanoparticles 9. Moreover, poly-Si thin-film cells do not requires a passivating layer and the flat base-shaped nanoparticles (that naturally result from thermal annealing of a metal film) can be directly placed on silicon further increases plasmonic scattering efficiency due to surface plasmon-polariton resonance 10.
The cell with the plasmonic nanoparticle array as described above can have a photocurrent about 28% higher than the original cell. However, the array still transmits a significant amount of light which escapes through the rear of the cell and does not contribute into the current. This loss can be mitigated by adding a rear reflector to allow catching transmitted light and re-directing it back to the cell. Providing sufficient distance between the reflector and the nanoparticles (a few hundred nanometers) the reflected light will then experience one more plasmonic scattering event while passing through the nanoparticle array on re-entering the cell and the reflector itself can be made diffuse - both effects further facilitating light scattering and hence light-trapping. Importantly, the Ag nanoparticles have to be encapsulated with an inert and low refractive index dielectric, like MgF2 or SiO2, from the rear reflector to avoid mechanical and chemical damage 7. Low refractive index for this cladding layer is required to maintain a high coupling fraction into silicon and larger scattering angles, which are ensured by the high optical contrast between the media on both sides of the nanoparticle, silicon and dielectric 6. The photocurrent of the plasmonic cell with the diffuse rear reflector can be up to 45% higher than the current of the original cell or up to 25% higher than the current of an equivalent cell with the diffuse reflector only.

Polycrystalline silicon thin-film solar cells on glass are fabricated by deposition of boron and phosphorous doped silicon layers followed by crystallisation, defect passivation and metallisation. Plasmonic light-trapping is introduced by forming Ag nanoparticles on the silicon cell surface capped with a diffused reflector resulting in ~45% photocurrent enhancement.

プラズモニック·強化されたライトトラップによる多結晶シリコン薄膜太陽電池

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To ...

工学

Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials.
Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4.
To promote a photovoltaic charge separation, we use a composite two-layer solid of PbS and TiO2 films. In this configuration, photoinduced electrons are injected into TiO2 and are subsequently picked up by an FTO electrode, while holes are channeled to a Au electrode via PbS layer6. To develop the latter we introduce a Semiconductor Matrix Encapsulated Nanocrystal Arrays (SMENA) strategy, which allows bonding PbS NCs into the surrounding matrix of CdS semiconductor. As a result, fabricated solids exhibit excellent thermal stability, attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells7.

A general strategy for the development of charge-separating semiconductor nanocrystal composites deployable for solar energy production is presented. We show that assembly of donor-acceptor nanocrystal domains in a single nanoparticle geometry gives rise to a photocatalytic function, while bulk-heterojunctions of donor-acceptor nanocrystal films can be used for photovoltaic energy conversion.

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials ...

Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped crystallites. Neutrons are passed through two well defined regions of magnetic field; one before and one after the sample. The two magnetic field regions have opposite polarity and are tuned such that neutrons travelling through both regions, without being perturbed, will undergo the same number of precessions in opposing directions. In this case the neutron precession in the second arm is said to &#34;echo&#34; the first, and the original polarization of the beam is preserved. If the neutron interacts with a sample and scatters elastically the path through the second arm is not the same as the first and the original polarization is not recovered. Depolarization of the neutron beam is a highly sensitive probe at very small angles (&#60;50&#160;&#956;rad) but still allows a high intensity, divergent beam to be used. The decrease in polarization of the beam reflected from the sample as compared to that from the reference sample can be directly related to structure within the sample.
In comparison to scattering observed in neutron reflection measurements the SERGIS signals are often weak and are unlikely to be observed if the in-plane structures within the sample under investigation are dilute, disordered, small in size and polydisperse or the neutron scattering contrast is low. Therefore, good results will most likely be obtained using the SERGIS technique if the sample being measured consist of thin films on a flat substrate and contain scattering features that contains a high density of moderately sized features (30 nm to 5 &#181;m) which scatter neutrons strongly or the features are arranged on a lattice. An advantage of the SERGIS technique is that it can probe structures in the plane of the sample.

Progress has been made in utilizing spin echo resolved grazing incidence scattering (SERGIS) as a neutron scattering technique to probe the length-scales in irregular samples. Crystallites of [6,6]-phenyl-C61-butyric acid methyl ester have been probed using the SERGIS technique and the results confirmed by optical and atomic force microscopy.

中性子スピンエコーを使用して放牧発生率散乱を解決し、有機太陽電池材料を調査する

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped ...

Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (&#181;c-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated &#181;c-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach.

A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

転写印刷により水素化微結晶シリコン太陽電池の光トラッピング銀ナノ構造の統合

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

バルクヘテロ接合太陽電池の印刷作製と<em&gt;その場で</em&gt;形態キャラクタリゼーション

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Fabrication of Fully Solution Processed Inorganic Nanocrystal Photovoltaic Devices

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal inks. For the photoactive absorber layer, colloidal CdTe and CdSe nanocrystals (3-5 nm) are synthesized using an inert hot injection technique and cleaned with precipitations to remove excess starting reagents. Similarly, gold nanocrystals (3-5 nm) are synthesized under ambient conditions and dissolved in organic solvents. In addition, precursor solutions for transparent conductive indium tin oxide (ITO) films are prepared from solutions of indium and tin salts paired with a reactive oxidizer. Layer-by-layer, these solutions are deposited onto a glass substrate following annealing (200-400 &#176;C) to build the nanocrystal solar cell (glass/ITO/CdSe/CdTe/Au). Pre-annealing ligand exchange is required for CdSe and CdTe nanocrystals where films are dipped in NH4Cl:methanol to replace long-chain native ligands with small inorganic Cl- anions. NH4Cl(s) was found to act as a catalyst for the sintering reaction (as a non-toxic alternative to the conventional CdCl2(s) treatment) leading to grain growth (136&#177;39 nm) during heating. The thickness and roughness of the prepared films are characterized with SEM and optical profilometry. FTIR is used to determine the degree of ligand exchange prior to sintering, and XRD is used to verify the crystallinity and phase of each material. UV/Vis spectra show high visible light transmission through the ITO layer and a red shift in the absorbance of the cadmium chalcogenide nanocrystals after thermal annealing. Current-voltage curves of completed devices are measured under simulated one sun illumination. Small differences in deposition techniques and reagents employed during ligand exchange have been shown to have a profound influence on the device properties. Here, we examine the effects of chemical (sintering and ligand exchange agents) and physical treatments (solution concentration, spray-pressure, annealing time and annealing temperature) on photovoltaic device performance.

This protocol describes the synthesis and solution deposition of inorganic nanocrystals layer by layer to produce thin film electronics on non-conductive surfaces. Solvent-stabilized inks can produce complete photovoltaic devices on glass substrates via spin and spray coating following post-deposition ligand exchange and sintering.

完全に解決策が処理無機ナノ結晶太陽電池素子の作製

We demonstrate a method for the preparation of fully solution processed inorganic solar cells from a spin and spray coating deposition of nanocrystal ...

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance

Hybrid organic/inorganic halide perovskites have lately been a topic of great interest in the field of solar cell applications, with the potential to achieve device efficiencies exceeding other thin film device technologies. Yet, large variations in device efficiency and basic physical properties are reported. This is due to unintentional variations during film processing, which have not been sufficiently investigated so far. We therefore conducted an extensive study of the morphology and electronic structure of a large number of CH3NH3PbI3 perovskite where we show how the preparation method as well as the mixing ratio of educts methylammonium iodide and lead(II) iodide impact properties like film formation, crystal structure, density of states, energy levels, and ultimately the solar cell performance.

We present an extensive study on the effects of different fabrication methods for organic/inorganic perovskite thin films by comparing crystal structures, density of states, energy levels, and ultimately the solar cell performance.

製膜上のハイブリッドペロブスカイト製造方法、電子構造、および太陽電池の性能に及ぼす影響

Hybrid organic/inorganic halide perovskites have lately been a topic of great interest in the field of solar cell applications, with the potential to ...

化学

Indoor Experimental Assessment of the Efficiency and Irradiance Spot of the Achromatic Doublet on Glass (ADG) Fresnel Lens for Concentrating Photovoltaics

We present a method to characterize achromatic Fresnel lenses for photovoltaic applications. The achromatic doublet on glass (ADG) Fresnel lens is composed of two materials, a plastic and an elastomer, whose dispersion characteristics (refractive index variation with wavelength) are different. We first designed the lens geometry and then used ray-tracing simulation, based on the Monte Carlo method, to analyze its performance from the point of view of both optical efficiency and the maximum attainable concentration. Afterwards, ADG Fresnel lens prototypes were manufactured using a simple and reliable method. It consists of a prior injection of plastic parts and a consecutive lamination, together with the elastomer and a glass substrate to fabricate the parquet of ADG Fresnel lenses. The accuracy of the manufactured lens profile is examined using an optical microscope while its optical performance is evaluated using a solar simulator for concentrator photovoltaic systems. The simulator is composed of a xenon flash lamp whose emitted light is reflected by a parabolic mirror. The collimated light has a spectral distribution and an angular aperture similar to the real Sun. We were able to assess the optical performance of the ADG Fresnel lenses by taking photographs of the irradiance spot cast by the lens using a charge-coupled device (CCD) camera and measuring the photocurrent generated by several types of multi junction (MJ) solar cells, which have been previously characterized at a solar simulator for concentrator solar cells. These measurements have demonstrated the achromatic behavior of ADG Fresnel lenses and, as a consequence, the suitability of the modelling and manufacturing methods.

Indoor Experimental Assessment of the Efficiency and Irradiance Spot of the Achromatic Doublet on Glass ADG Fresnel Lens for Concentrating Photovoltaics

The achromatic doublet on glass (ADG) Fresnel lens makes use of two materials with differing dispersion to reduce chromatic aberration and increase attainable concentration. In this paper, a protocol for the complete characterization of the ADG Fresnel lens is presented.

効率と集中太陽光発電用ガラス (ADG) フレネル レンズの色消しの放射照度場所の屋内の実験的評価

We present a method to characterize achromatic Fresnel lenses for photovoltaic applications. The achromatic doublet on glass (ADG) Fresnel lens is ...

Developing High Performance GaP/Si Heterojunction Solar Cells

To improve the efficiency of Si-based solar cells beyond their Shockley-Queisser limit, the optimal path is to integrate them with III-V-based solar cells. In this work, we present high performance GaP/Si heterojunction solar cells with a high Si minority-carrier lifetime and high crystal quality of epitaxial GaP layers. It is shown that by applying phosphorus (P)-diffusion layers into the Si substrate and a SiNx layer, the Si minority-carrier lifetime can be well-maintained during the GaP growth in the molecular beam epitaxy (MBE). By controlling the growth conditions, the high crystal quality of GaP was grown on the P-rich Si surface. The film quality is characterized by atomic force microscopy and high-resolution x-ray diffraction. In addition, MoOx was implemented as a hole-selective contact that led to a significant increase in the short-circuit current density. The achieved high device performance of the GaP/Si heterojunction solar cells establishes a path for further enhancement of the performance of Si-based photovoltaic devices.

Here, we present a protocol to develop high-performance GaP/Si heterojunction solar cells with a high Si minority-carrier lifetime.

高パフォーマンス ギャップ/Si ヘテロ接合太陽電池の開発

To improve the efficiency of Si-based solar cells beyond their Shockley-Queisser limit, the optimal path is to integrate them with III-V-based solar ...

In situ Grazing Incidence Small Angle X-ray Scattering on Roll-To-Roll Coating of Organic Solar Cells with Laboratory X-ray Instrumentation

We present an in-house, in situ Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiment, developed to probe the drying kinetics of roll-to-roll slot-die coating of the active layer in organic photovoltaics (OPVs), during deposition. For this demonstration, the focus is on the combination of P3HT:O-IDTBR and P3HT:EH-IDTBR, which have different drying kinetics and device performance, despite their chemical structure only varying slightly by the sidechain of the small molecule acceptor. This article provides a step-by-step guide to perform an in situ GISAXS experiment and demonstrates how to analyze and interpret the results. Usually, performing this type of in situ X-ray experiments to investigate the drying kinetics of the active layer in OPVs relies on access to synchrotrons. However, by using and further developing the method described in this paper, it is possible to perform experiments with a coarse temporal and spatial resolution, on a day-to-day basis to gain fundamental insight in the morphology of drying inks.

This paper is a demonstration and a guideline to perform and analyze in-house (with a laboratory X-ray instrument) in situ GISAXS experiments of drying inks on roll-to-roll slot-die coated, non-fullerene organic photovoltaics.

実験室X線計装による有機太陽電池のロールツーロールコーティングにおけるその場放牧発生率小角X線散乱

We present an in-house, in situ Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiment, developed to probe the drying kinetics of roll-to-roll ...

集中太陽光発電システムにおけるスペクトル分割分散素子の高コントラスト回折格子の作製

要約

さらに動画を探す

この動画の章

プラズモニック·強化されたライトトラップによる多結晶シリコン薄膜太陽電池

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

中性子スピンエコーを使用して放牧発生率散乱を解決し、有機太陽電池材料を調査する

転写印刷により水素化微結晶シリコン太陽電池の光トラッピング銀ナノ構造の統合

バルクヘテロ接合太陽電池の印刷作製と

完全に解決策が処理無機ナノ結晶太陽電池素子の作製

製膜上のハイブリッドペロブスカイト製造方法、電子構造、および太陽電池の性能に及ぼす影響

効率と集中太陽光発電用ガラス (ADG) フレネルレンズの色消しの放射照度場所の屋内の実験的評価

高パフォーマンスギャップ/Si ヘテロ接合太陽電池の開発

実験室X線計装による有機太陽電池のロールツーロールコーティングにおけるその場放牧発生率小角X線散乱

集中太陽光発電システムにおけるスペクトル分割分散素子の高コントラスト回折格子の作製

要約

さらに動画を探す

この動画の章

プラズモニック·強化されたライトトラップによる多結晶シリコン薄膜太陽電池

電荷分離ナノ結晶とその固体の手段によって太陽エネルギーを収穫

中性子スピンエコーを使用して放牧発生率散乱を解決し、有機太陽電池材料を調査する

転写印刷により水素化微結晶シリコン太陽電池の光トラッピング銀ナノ構造の統合

バルクヘテロ接合太陽電池の印刷作製と

完全に解決策が処理無機ナノ結晶太陽電池素子の作製

製膜上のハイブリッドペロブスカイト製造方法、電子構造、および太陽電池の性能に及ぼす影響

効率と集中太陽光発電用ガラス (ADG) フレネル レンズの色消しの放射照度場所の屋内の実験的評価

高パフォーマンス ギャップ/Si ヘテロ接合太陽電池の開発

実験室X線計装による有機太陽電池のロールツーロールコーティングにおけるその場放牧発生率小角X線散乱

効率と集中太陽光発電用ガラス (ADG) フレネルレンズの色消しの放射照度場所の屋内の実験的評価

高パフォーマンスギャップ/Si ヘテロ接合太陽電池の開発