Sains Malaysiana 49(8)(2020): 1875-1890

http://dx.doi.org/10.17576/jsm-2020-4908-10

Opto-Electrical Investigation of Zn Metal-Doped Cds and Their Application in Soft Lithographic Technique

(Kajian Opto-Elektrik ke atas Zn Logam-terdop Cd dan Aplikasinya dalam Teknik Litografi Lembut)

GULALAI HUSSAIN¹, UZMA JABEEN¹*, IRFAN HAFEEZ², M NAJAM KHAN MALGHANI³, AYESHA MUSHTAQ¹*, SABEENA RIZWAN¹, FARRUKH BASHIR¹, FARIDA BEHLIL¹, M AAMIR RAZA² & SHAISTA ANJUM⁴

¹Faculty of Basic Sciences, SBK Women’s University Quetta, 87300, Pakistan

²Pakistan Council of Scientific and Industrial Research, Pakistan

³Faculty of Engineering and Architecture, Takatu campus BUITEMS Quetta, Pakistan

⁴Faculty of Life Sciences, University of Balochistan, Quetta, Pakistan

Received: 12 October 2019/Accepted: 26 March 2020

ABSTRACT

Un-doped CdS and Zn metal-doped CdS (0.1-0.5 M) were synthesized by chemical precipitation method. Properties like optical band gap and conductivity were determined by different characterization techniques. UV-Visible spectroscopy was applied to estimate the band gap where it showed a significant blue shift due to quantum confinement effect. Size determined by scanning electron microscopy (SEM) was found to be in nanorange from 41 to 60 nm for both un-doped and metal doped CdS nanocrystals. EDAX confirmed the doping by showing peak for Zn. XRD (X-ray diffraction) showed the lattice structure to be cubic for the synthesized nanoparticles and conductivity for un-doped CdS was 7.69E-6 Ω^-1m-¹ where it changes to 9.25E-6 Ω^-1m-¹ and 7.98E-6 Ω^-1m-¹ for 0.2 M and 0.5 M Zn-doped CdS, respectively. In order to obtain good results, nanocrystals having highest conductivity are used in soft lithographic technique. Here µTM (micro transfer-molding) was followed for patterning with PDMS (poly-(dimethylsiloxane)) mold and silicon substrate for better results.

Keywords: Band gap; blue shift; conductivity; lithography; Zn dopant

ABSTRAK

CdS yang tidak terdop dan Zn logam-terdop (0.1-0.5M) disintesis dengan kaedah pemendakan kimia. Sifat seperti jurang jalur optik dan kekonduksian ditentukan oleh teknik pencirian yang berbeza. Spektroskopi Terlihat UV diterapkan untuk menganggarkan jurang jalur yang menunjukkan peralihan warna biru yang ketara kerana kesan pengurungan kuantum. Ukuran yang ditentukan oleh mikroskopi elektron pengimbasan (SEM) didapati berada dalam jarak nano dari 41 hingga 60 nm untuk kristal nano CdS yang tidak dilekatkan dan logam. EDAX mengesahkan pendopan dengan menunjukkan puncak untuk Zn. XRD (difraksi sinar-X) menunjukkan struktur kisi menjadi kubik bagi zarah nanopartesis yang disintesis dan kekonduksian untuk CdS tanpa pendopan adalah 7.69E-6 Ω^-1m^-1 dan ia berubah menjadi 9.25E-6 Ω^-1m^-1 dan 7.98E-6 Ω^-1m^-1 masing-masing untuk 0.2 M dan 0.5 M Zn-terdop CdS. Untuk memperoleh hasil yang baik, kristal nano yang mempunyai kekonduksian tertinggi digunakan dalam teknik litografi lembut. Di sini µTM (acuan pemindahan mikro) dilakukan untuk membuat corak dengan substrat acuan dan silikon PDMS (poli- (dimetilsiloksana)) untuk hasil yang lebih baik.

Kata kunci: Jurang jalur; kekonduksian; litografi; peralihan biru; Zn dopan

REFERENCES

Brus, L. & Jocp, T. 1984. Electron-electron and electron‐hole interactions in small semiconductor crystallites: The size dependence of the lowest excited electronic state. The Journal of Chemistry Physics 80: 4403-4409.

Erwin, S.C., Zu, L., Haftel, M.I., Efros, A.L., Kennedy, T.A. & Norris, D.J. 2005. Doping semiconductor nanocrystals. Nature 436(7047): 91-94.

Huse, V.R., Mote, V.D. & Dole, B.N. 2013. The crystallographic and optical studies on cobalt doped CdS nanoparticles. World Journal of Condensed Matter Physics 3(1): 46-49.

Irem, F.E. & Boz, I. 2017. Synthesis and characterization of metal-doped (Ni, Co, Ce, Sb) CdS catalysts and their use in methylene blue degradation under visible light irradiation. Modern Research in Catalysis 6(1): 1-14.

Kane, R.S., Takayama, S., Ostuni, E., Ingber, D.E. & Whitesides, G.M. 1999. Patterning proteins and cells using soft lithography. Biomaterials 20(23-24): 161-174.

Kazmerski, L.L. 2006. Solar photovoltaics R&D at the tipping point: A 2005 technology overview. Journal of Electron Spectroscopy and Related Phenomena 150(2-3): 105-135.

Khan, S.U., Göbel, O.F., Blank, D.H.A. & Elshof, J.E. 2009. Patterning lead zirconate titanate nanostructures at sub-200-nm resolution by soft confocal imprint lithography and nanotransfer molding. Applied Materials & Interfaces 1(10): 2250-2255.

Murugadoss, G. 2012. Luminescence properties of multilayer coated single structure ZnS/CdS/ZnS nanocomposites. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 93: 53-57.

Jabeen, U., Shah, S.M., Hussain, N., Ali, A. & Khan, S.U. 2016. Synthesis, characterization, band gap tuning and applications of Cd-doped ZnS nanoparticles in hybrid solar cells. Journal of Photochemistry and Photobiology A: Chemistry 325: 29-38.

Xia, Y. & Whitesides, G.M. 1998. Soft lithography. Annual Review of Materials Science 28: 153-184.

Wu, X. 2004. High-efficiency polycrystalline CdTe thin-film solar cells. Solar Energy 77(6): 803-814.

Zheng, B., Roach, L.S. & Ismagilov, R.F. 2003. Screening of protein crystallization conditions on a microfluidic chip using nanoliter-size droplets. Journal of the American Chemical Society 125(37): 11170-11171.

*Corresponding author; email: roha64@yahoo.com