Sains Malaysiana 45(8)(2016): 1213–1219

The Effect of Al(NO₃)₃ Concentration on the Formation of AuNPs using Low Temperature Hydrothermal Reaction for Memory Application

(Kesan Kepekatan Al(NO₃)₃ ke atas Pembentukan AuNPs dengan Menggunakan Tindak Balas Hidroterma Suhu Rendah untuk Aplikasi Ingatan)

S.A. NG¹, K.A. RAZAK,^1,2*, K.Y. CHEONG¹, K.C. AW³

¹School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia

²NanoBiotechnology Research and Innovation, INFORMM, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia

³Mechanical Engineering, The University of Auckland, Auckland, New Zealand

Diserahkan: 20 April 2015/Diterima: 18 November 2015

ABSTRACT

Distribution of gold nanoparticles (AuNPs) on a substrate becomes crucial in nanotechnology applications. This work describes a route to fabricate AuNPs directly on silicon substrates by using an aluminum template in hydrothermal reaction at 80°C for 1 h. The effect of aluminum nitrate (Al(NO₃)₃) concentration in the hydrothermal bath was investigated. The properties of AuNPs were studied using field-emission scanning electron microscope (FESEM), x-ray diffractometer (XRD) and semiconductor characterization system (SCS). Two distinct sizes of AuNPs were observed by FESEM. XRD analysis proved the formation of AuNPs directly on the substrate. AuNPs were embedded between polymethylsilsesquioxane (PMSSQ) in order to investigate their effect on memory properties. The sample grown in 0.1 M Al(NO₃)₃ exhibited the largest hysteresis window (2.6 V) and the lowest Vth (2.2 V) to turn ‘ON’ the memory device. This indicated that good distribution of FCC structure AuNPs with 80±4 nm and 42±7 nm of large and small particles produced better charge storage capability. Charge transport mechanisms of AuNPs embedded in PMSSQ were explained in details whereby electrons from Si are transported across the barrier by thermionic effects via field-assisted lowering at the Si-PMSSQ interface with the combination of the Schottky and Poole Frenkel emission effect in Region 1. Trapped charge limited current (TCLC) and space charge limited current (SCLC) transport mechanism occurred in Region 2 and Region 3.

Keywords: Gold nanoparticles; hydrothermal; memory devices; template

ABSTRAK

Taburan nanopartikel emas (AuNPs) pada substrat adalah penting dalam aplikasi nanoteknologi. Kajian ini menerangkan cara untuk menghasilkan AuNPs secara langsung di atas substrat silikon dengan menggunakan templat aluminium dalam tindak balas hidroterma pada suhu 80°C selama 1 jam. Kesan kepekatan aluminium nitrat (Al(NO3)3) dalam rendaman hidroterma dikaji. Sifat AuNPs telah dikaji menggunakan pancaran medan mikroskop elektron imbasan (FESEM), pembelauan sinar-x (XRD) dan sistem pencirian semikonduktor (SCS). Dua saiz berbeza AuNPs diperhatikan menggunakan FESEM. Analisis XRD membuktikan pembentukan AuNPs secara langsung ke atas substrat. AuNPs tertanam antara polimetilsilseskuioksana (PMSSQ) untuk mengkaji kesannya ke atas sifat ingatan. Sampel yang dihasilkan di dalam 0.1 M Al(NO3)3 menghasilkan tetingkap histeresis terbesar (2.6 V) dan Vth (2.2 V) terendah untuk menghidupkan peranti ingatan. Ini menunjukkan pengagihan yang baik oleh struktur FCC AuNPs dengan 80±4 nm dan 42±7 nm partikel besar dan kecil menghasilkan keupayaan penyimpanan cas yang lebih baik. Mekanisme pengangkutan cas di dalam AuNPs tertanam dalam PMSSQ telah dijelaskan secara terperinci manakala elektron daripada Si diangkut merentasi halangan oleh kesan termionik melalui perendahan medan-berbantu pada antara muka Si-PMSSQ dengan gabungan kesan pancaran Schottky dan Poole Frenkel dalam Rantau 1. Mekanisme pengangkutan perangkap arus cas terhad (TCLC) dan ruang arus cas terhad (SCLC) berlaku di Rantau 2 dan 3.

Kata kunci: Hidroterma; nanopartikel emas; peranti ingatan; templat

RUJUKAN

Ahmad, Z., Ooi, P.C., Aw, K.C. & Sayyad, M.H. 2011. Electrical characteristics of poly(Methylsilsesquioxane) thin films for non-volatile memory. Solid State Communications 151(4): 297-300.

Cao, L., Zhu, T. & Liu, Z. 2006. Formation mechanism of nonspherical gold nanoparticles during seeding growth: Roles of anion adsorption and reduction rate. Journal of Colloid and Interface Science 293(1): 69-76.

Daniel, M.C. & Astruc, D. 2004. Gold nanoparticles: Assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. Chemical Reviews 104(1): 293-346.

Das, A., Das, S. & Raychaudhuri, A.K. 2008. Growth of two-dimensional arrays of uncapped gold nanoparticles on silicon substrates. Bulletin of Materials Science 31(3): 277-282.

Goh, L., Razak, K., Ridhuan, N., Cheong, K., Ooi, P. & Aw, K. 2012. Direct formation of gold nanoparticles on substrates using a novel zno sacrificial templated-growth hydrothermal approach and their properties in organic memory device. Nanoscale Research Letters 7(1): 563.

Gowd, E.B., Nandan, B., Bigall, N.C., Eychmüller, A., Formanek, P. & Stamm, M. 2010. Hexagonally ordered arrays of metallic nanodots from thin films of functional block copolymers. Polymer 51(12): 2661-2667.

Granmayeh Rad, A., Abbasi, H. & Afzali, M.H. 2011. Gold nanoparticles: Synthesising, characterizing and reviewing novel application in recent years. Physics Procedia 22: 203-208.

Gupta, B., Melvin, A. & Prakash, R. 2014. Synthesis of polyanthranilic acid-au nanocomposites by emulsion polymerization: Development of dopamine sensor. Bulletin of Materials Science 37(6): 1389-1395.

Haensch, C., Hoeppener, S. & Schubert, U.S. 2010. Chemical modification of self-assembled silane based monolayers by surface reactions. Chemical Society Reviews 39(6): 2323- 2334.

Kim, T.W., Yang, Y., Li, F. & Kwan, W.L. 2012. Electrical memory devices based on inorganic/organic nanocomposites. NPG Asia Materials 4: e18.

Lai, Y.C., Wang, D.Y., Huang, I.S., Chen, Y.T., Hsu, Y.H., Lin, T.Y., Meng, H.F., Chang, T.C., Yang, Y.J., Chen, C.C., Hsu, F.C. & Chen, Y.F. 2013. Low operation voltage macromolecular composite memory assisted by graphene nanoflakes. Journal of Materials Chemistry C 1(3): 552-559.

Lee, J.S. 2010. Recent progress in gold nanoparticle-based non-volatile memory devices. Gold Bulletin 43(3): 189-199.

Liu, C.H. & Yu, X. 2011. Silver nanowire-based transparent, flexible, and conductive thin film. Nanoscale Res. Lett. 6(1): 75.

Mantri, K., Selvakannan, P., Tardio, J. & Bhargava, S.K. 2013. Synthesis of very high surface area au-sba-15 materials by confinement of gold nanoparticles formation within silica pore walls. Colloids and Surfaces A: Physicochemical and Engineering Aspects 429: 149-158.

Mark, P.R. 2013. Forces and interactions between nanoparticles for controlled structures. PhD Thesis. Rutgers University- Graduate School-New Brunswick (Unpublished).

Masala, O. & Seshadri, R. 2004. Synthesis routes for large volumes of nanoparticles. Annu. Rev. Mater. Res. 34: 41-81.

Ng, S.A., Razak, K.A., Goh, L.P., Cheong, K.Y., Ooi, P.C. & Aw, K.C. 2014. Direct formation of aunps thin film using thermal evaporated zinc as sacrificial template in hydrothermal method. Journal of Materials Science: Materials in Electronics 25(5): 2227-2236.

Park, B., Im, K.J., Cho, K. & Kim, S. 2008. Electrical characteristics of gold nanoparticle-embedded mis capacitors with parylene gate dielectric. Organic Electronics 9(5): 878-882.

Paul, S., Pearson, C., Molloy, A., Cousins, M., Green, M., Kolliopoulou, S., Dimitrakis, P., Normand, P., Tsoukalas, D. & Petty, M. 2003. Langmuir-Blodgett film deposition of metallic nanoparticles and their application to electronic memory structures. Nano Letters 3: 533-536.

Philip, D. 2008. Synthesis and spectroscopic characterization of gold nanoparticles. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 71(1): 80-85.

Raznjevic, K. 1976. Handbook of Thermodynamic Tables and Charts. Philadelphia: Hemisphere Publishing Corporation.

Sethuraman, K., Ochiai, S., Kojima, K. & Mizutani, T. 2008. Performance of poly(3-hexylthiophene) organic field-effect transistors on cross-linked poly(4-vinyl phenol) dielectric layer and solvent effects. Applied Physics Letters 92(18): 183302.

Sun, X., Fu, Z. & Wu, Z. 2002. Fractal processing of afm images of rough zno films. Materials Characterization 48(2-3): 169-175.

Taleghani, M. & Riahi-Noori, N. 2013. Synthesis of alumina nano powder by a gel combustion method. Journal of Ceramic Processing Research 14(1): 17-21.

Thanh, N.T. & Green, L.A. 2010. Functionalisation of nanoparticles for biomedical applications. Nano Today 5(3): 213-230.

Ward, C.J., Tronndorf, R., Eustes, A.S., Auad, M.L. & Davis, E.W. 2014. Seed-mediated growth of gold nanorods: limits of length to diameter ratio control. Journal of Nanomaterials 2014: Article ID 765618.

*Pengarang untuk surat menyurat; email: khairunisak@usm.my