Black silicon is a promising semiconductor material for photovoltaic (PV) application due to its superior light absorption within 300–1100 wavelength region. Aluminium-assisted chemical etching (AACE) demonstrates superior control over surface morphology and optical properties of black silicon for solar cell application. In this work, role of aluminium film thickness as catalyst for nanoporous black silicon fabrication was investigated. Aluminium film thicknesses (15–30 nm) were deposited on monocrystalline silicon (mono c-Si) wafers, followed by wet chemical etching of the wafers in hydrofluoric acid, hydrogen peroxide and deionize water (HF:H2O2:H2O) solution, respectively, with volume ratio of 4:7:10 ml. The 25 nm aluminium film produced the lowest weighted average reflection <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10854_2025_15828_Article_IEq1.gif" Format="GIF" Height="20" Rendition="HTML" Resolution="72" Type="Linedraw" Width="46" /> </InlineMediaObject> <EquationSource Format="TEX">$({R}_{avg})$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mo stretchy="false">(</mo> <msub> <mi>R</mi> <mrow> <mi mathvariant="italic">avg</mi> </mrow> </msub> <mo stretchy="false">)</mo> </mrow> </math></EquationSource> </InlineEquation> of 6.71% in the black silicon within the 300–1100 nm wavelength region. The black silicon exhibits surface coverage of 41.5%, average pore depth of 187 nm and root mean square (RMS) surface roughness of 26.1 nm. In the b-Si solar cell, diffused emitter electron concentration (<InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10854_2025_15828_Article_IEq2.gif" Format="GIF" Height="12" Rendition="HTML" Resolution="72" Type="Linedraw" Width="19" /> </InlineMediaObject> <EquationSource Format="TEX">${n}_{e}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>n</mi> <mi>e</mi> </msub> </math></EquationSource> </InlineEquation>), short-circuit current (<InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10854_2025_15828_Article_IEq3.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="23" /> </InlineMediaObject> <EquationSource Format="TEX">${J}_{sc}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>J</mi> <mrow> <mi mathvariant="italic">sc</mi> </mrow> </msub> </math></EquationSource> </InlineEquation>), and open circuit voltage (<InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10854_2025_15828_Article_IEq4.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="24" /> </InlineMediaObject> <EquationSource Format="TEX">${V}_{oc}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>V</mi> <mrow> <mi mathvariant="italic">oc</mi> </mrow> </msub> </math></EquationSource> </InlineEquation>) of <InlineEquation ID="IEq5"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10854_2025_15828_Article_IEq5.gif" Format="GIF" Height="18" Rendition="HTML" Resolution="72" Type="Linedraw" Width="115" /> </InlineMediaObject> <EquationSource Format="TEX">$7.64\times {10}^{17}{\text{cm}}^{-3}$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mn>7.64</mn> <mo>×</mo> <msup> <mrow> <mn>10</mn> </mrow> <mn>17</mn> </msup> <msup> <mrow> <mtext>cm</mtext> </mrow> <mrow> <mo>-</mo> <mn>3</mn> </mrow> </msup> </mrow> </math></EquationSource> </InlineEquation>, 18.7 mA/cm2 and 507.2 mV have been obtained, leading to 9.9% of power conversion efficiency. The findings highlight the potential of the AACE to produce efficient black silicon photovoltaic devices.

Role of aluminium film thickness as catalyst in formation of nanoporous black silicon for solar cell application

期刊论文
发表日期：

2025年10月13日

查看全文

Suleman Kazim Omotayo,
Shahnawaz Uddin,
Peverga Rex Jubu,
Aminu Muhammad,
Mohd Marzaini Mohd Rashid,
Mohd Zamir Pakhuruddin

摘要

Black silicon is a promising semiconductor material for photovoltaic (PV) application due to its superior light absorption within 300–1100 wavelength region. Aluminium-assisted chemical etching (AACE) demonstrates superior control over surface morphology and optical properties of black silicon for solar cell application. In this work, role of aluminium film thickness as catalyst for nanoporous black silicon fabrication was investigated. Aluminium film thicknesses (15–30 nm) were deposited on monocrystalline silicon (mono c-Si) wafers, followed by wet chemical etching of the wafers in hydrofluoric acid, hydrogen peroxide and deionize water (HF:H₂O₂:H₂O) solution, respectively, with volume ratio of 4:7:10 ml. The 25 nm aluminium film produced the lowest weighted average reflection $({R}_{avg})$ $(R_{avg})$ of 6.71% in the black silicon within the 300–1100 nm wavelength region. The black silicon exhibits surface coverage of 41.5%, average pore depth of 187 nm and root mean square (RMS) surface roughness of 26.1 nm. In the b-Si solar cell, diffused emitter electron concentration ( ${n}_{e}$ $n_{e}$ ), short-circuit current ( ${J}_{sc}$ $J_{sc}$ ), and open circuit voltage ( ${V}_{oc}$ $V_{oc}$ ) of $7.64\times {10}^{17}{\text{cm}}^{-3}$ $7.64 \times 10^{17} {cm}^{- 3}$ , 18.7 mA/cm² and 507.2 mV have been obtained, leading to 9.9% of power conversion efficiency. The findings highlight the potential of the AACE to produce efficient black silicon photovoltaic devices.