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We use temperature-dependent contact resistivity (ρc) measurements to systematically assess the dominant electron transport mechanism in a large set of poly-Si passivating contacts, fabricated by varying (i) the annealing temperature (Tann), (ii) the oxide thickness (tox), (iii) the oxidation method, and (iv) the surface morphology of the Si substrate. The results show that for silicon oxide thicknesses of 1.3–1.5 nm, the dominant transport mechanism changes from tunneling to drift-diffusion via pinholes in the SiOx layer for increasing Tann. This transition occurs for Tann in the range of 850°C-950 °C for a 1.5 nm thick thermal oxide, and 700°C-750 °C for a 1.3 nm thick wet-chemical oxide, which suggests that pinholes appear in wet-chemical oxides after exposure to lower thermal budgets compared to thermal oxides. For SiOx with tox = 2 nm, grown either thermally or by plasma-enhanced atomic layer deposition, carrier transport is pinhole-dominant for Tann = 1050 °C, whereas no electric current through the SiOx layer could be detected for lower Tann. Remarkably, the dominant transport mechanism is not affected by the substrate surface morphology, although lower values of ρc were measured on textured wafers compared to planar surfaces. Lifetime measurements suggest that the best carrier selectivity can be achieved by choosing Tann right above the transition range, but not too high, in order to induce pinhole dominant transport while preserving a good passivation quality.

In this paper we propose a possible process simplification for pseudosquare 15.6×15.6 cm 2 Interdigitated Back Contact (IBC) CZ-Si solar cells. By using laser doping to create a selective BSF, one out of three diffusions and a wet etching step can be avoided, compared to a completely diffusion-based process flow. We show numerical optimization of this simplified cell structure in terms of: i) rear optics with additional SiN x capping layer, ii) contact fraction of the selective BSF. The results feature a top cell efficiency of 21.7% measured over the area of 239 cm 2 . Further characterization implies that cells were limited mainly by: i) FF losses attributed to lateral majority carrier transport in the BSF region and increased J 02 losses, ii) current loss which can be related to the BSF region.

In this work, an industrially viable and novel rear surface passivation approach for Copper Indium Gallium di-Selenide, Cu(In,Ga)Se2, CIGS, ultra-thin (500nm) solar cells is developed. The passivation layer was deposited by atomic layer deposition (ALD), and an alkali treatment was applied via spin coating. It was observed that selenization of the samples is required to create contact openings. The openings were visualized by SEM, and these results were supported by EDS. The impact of the oxide layer’s thickness, as well as the alkali solution’s molarity, was studied. Solar cells were produced for the optimal combination of these two parameters. As a result, with a relative 13% increase, the highest Vocof 623mV was achieved. Hence, the efficiency of the passivated solar cell was relatively increased by one-third, by using an industrially feasible, fast, and repeatable technique.

All-thin film perovskite/CIGS multijunction solar modules, combining a semi-transparent perovskite top solar module stacked on a CIGS bottom solar module, are a promising route to surpass the efficiency limits of single-junction thin-film solar modules. In this work, we present a scalable thin-film perovskite/CIGS photovoltaic module with an area of 3.76 cm2 and a power conversion efficiency of 17.8%. Our prototype outperforms both the record single-junction perovskite solar module of the same area as well as the reference CIGS solar module. The presented perovskite/CIGS thin-film multijunction solar module makes use of the “4-terminal architecture”, which stacks the perovskite solar module in superstrate configuration on top of the CIGS solar module in substrate configuration. Both submodules apply a scalable interconnection scheme that can accommodate scale-up towards square meter scale thin-film multijunction solar modules. In order to identify the future potential of the presented stacked perovskite/CIGS thin-film solar module, we quantify the various losses in the presented prototype and identify the key challenges of this technology towards very high power conversion efficiencies.

Commercially available phenyl-C61-butyric acid methyl ester (PCBM) is crosslinked with 1,6-diazidohexane (DAZH), resulting in films resistant to common solvents used in perovskite solar cell processing. By using crosslinked PCBM as an interlayer and (HC(NH2)2)0.66(CH3NH3)0.34PbI2.85Br0.15 as the active layer, we achieve small area devices and modules with a maximum steady-state power conversion efficiency of 18.1% and 14.9%, respectively.

In this work, we evaluate by means of simulations and measurements the effect of rear surface morphology on the performance of n-type rear-junction Passivated Emitter Rear Totally-diffused (PERT) solar cells with epitaxial emitter. A comparison of the electrical and optical performance between a rear polished and a rear textured surface was conducted on both test structures and solar cells. The effect of surface morphology on J 0e for both emitters formed by either diffusion or epitaxy was investigated. It was found that epitaxy on a textured surface provides J 0e values even better than boron diffusion and J 0e for both surfaces (textured rear and polished rear) using ALD-Al 2 O 3 /PECVD SiO x as dielectric passivation are much lower than the ones by wet oxidation. A small difference in V oc between both surfaces was also predicted in our electrical simulations. Overall, the measurements show that n-type PERT solar cells with textured rear epitaxial emitter can perform at almost the same efficiency level to the ones with polished rear. For both types of n-PERT cells (textured rear and polished rear), average efficiencies ( η ) and short-circuit current densities ( J sc ) exceeding 20.5% and 39 mA/cm 2 , respectively were achieved on 238.9 cm 2 cells. Moreover, from our optical simulations it was found that either a textured rear surface or a non-perfect polished rear surface are ideal for light trapping at standard illumination conditions, with light impinging perpendicular onto the cell. However, a perfectly polished rear surface or one with pyramids at angles of 45° should be avoided. Finally, from a cost of ownership (CoO) point of view it was found that the potential efficiency gain originating from a rear polished surface is not cost effective. For polishing to become cost effective, the cell in the module should have an efficiency of 21.05% which is 0.45% more than the textured case.

Cu 2 ZnGeSe 4 (CZGeSe) can be considered as a potential alternative for wide band gap thin film devices. In this work, CZGeSe thin films were deposited on Mo-coated soda lime glass substrates by sequential deposition of sputtered Cu, Zn and e-beam evaporated Ge layers from elemental targets followed by annealing at high temperature using H 2 Se gas. We report on the effect of the precursor stack order and composition and the impact of the annealing temperature on the physical properties of CZGeSe thin films. The optimal layer morphology was obtained when using a Mo/Cu/Zn/Ge precursor stack annealed at 460 °C. We have observed that the formation of secondary phases such as ZnSe can be prevented by tuning the initial composition of the stack, the stack order and the annealing conditions. This synthesis process allows synthesizing CZGeSe absorber with an optical band gap of 1.5 eV.

This work studies the performance of commercially available Al pastes for the rear side contact formation with an industrially feasible process. The pastes are specifically designed for local Al-BSF/PERC (Passivated emitter and rear cell) cells. With this type of metallization, fill factors (FF) up to 80% are demonstrated, to our knowledge, the highest FF ever reported on fully screen printed PERC cells with industrial type emitter. Additionally, the use of an AlSi eutectic (12.7% Si) target for PVD sputtering is evaluated in comparison to a reference process using a pure Al target with the same kind of deposition technique. It was found that the thickness of the Al p+ BSF layer realized with the 12.7% Si containing Al target is systematically thicker than the reference due to a smaller metal Si interface. With this method, solar cells have been fabricated showing a potential efficiency above 20%, with standard Ag front screen printing on 60 Ω/□ emitter.

This work focuses on the mechanisms of alkaline electroless Ni deposition on n-type Si substrates and silicide formation by rapid thermal treatment. The deposited Ni layers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), and electron energy loss spectroscopy (EELS). The results indicate that Ni deposition occurs in two steps; a nucleation step, dominated by electrochemical processes, followed by autocatalytic deposition of Ni involving the reducing agent NaH2PO2. The oxygen content was found to be uniform in the Ni layer and was higher close to the Si/metal interface. The silicide formation from alkaline Ni deposits was characterized by 4 point probe measurements, in-situ x-ray dispersion (XRD) measurements, and TEM measurements. Results were compared to silicides formed from ‘pure’ sputtered Ni layers. It was observed that the silicide-formation temperature is higher for an electroless Ni layer than that for a sputtered Ni layer. The results suggest that the temperature ramping rate influences crystallographic phase formation.

In this work, an extensive characterisation of intrinsic amorphous silicon (a-Si) passivation layers deposited on n- and p-type silicon is reported. Low temperature capacitance-voltage measurements are utilised to enable parameter extraction from the c-Si/a-Si interface and a-Si bulk. Electron spin resonance enables atomic identification of defects present. Results reveal the presence of electrically active defects at the c-Si/intrinsic a-Si interface (∼1x1012 cm-2), and throughout the amorphous silicon layer bulk (∼8x1016 cm-3), which are atomically identified as Pb0 centres and D centres silicon dangling bond defects, respectively. The value of this work is the atomic identification of these defects in this stack, coupled with their electrical activity. That they can be detected by these techniques demonstrates the power of the methodology used to assess and quantify these defects. Therein lies the significance of this work: a methodology capable of fundamentally optimising amorphous silicon processing from an atomic perspective.

In this work, we report on a self-aligned nickel silicide formation technique based on excimer laser annealing (ELA). We evaluate this process for the front contact formation of industrial PERC type solar cells on random pyramid textured Si surfaces where damage to surface texture, emitter passivation, or to the shallow junction should be avoided or minimized. PERC type solar cells obtained by POCl3 diffusion were processed on large area (12.5x12.5 cm2) CZ-Si. Self-aligned litho-free Ni/Cu contacts defined by ps-laser ablation of the SiO2/SiNx anti-reflective coating (ARC) and subsequent ELA of the Ni layer were compared to conventional Ag screen printed contacts. The novel ELA process results in an absolute gain in Jsc of 0.8 mA/cm2 as well as a drop of 0.3 Ω.cm2 in series resistance (Rs) compared to SP Ag contacts due to reduced shading and resistance losses. This leads to 0.5% absolute increase in efficiency from 19.3% to 19.7% since other characteristics (Voc, pFF) could be maintained to the same level. In this work, the best performing cell with the ELA process reached an outstanding 20.0% energy conversion efficiency with Jsc=39.3 mA/cm2, Voc=649.8 mV, and FF=78.3%.

Excellent front surface passivation is one of the key issues for interdigitated back contact (IBC) silicon solar cells. To create a better understanding of passivation properties and find the most important issues when developing passivation schemes for various injection conditions, an advanced simulation model is needed. The software package Sentaurus TCAD is applied in this work. The main input parameters of the model are the interface state density, the amount of fixed charges, the capture cross sections and the activation energies which have been determined experimentally as reported previously. As an example, simulation results of the advanced model of the recombination at the Si-SiNx interface were presented and compared to the measured data.

This paper describes the realisation of cost-efficient thermophotovoltaic (TPV) cells based on germanium substrates. Because the majority of the photons incident on the TPV cell in a typical TPV system will have a long wavelength it is important to apply optical confinement in the TPV cell. In this paper this has been done by using a highly reflective rear contact. Electrical contact at the rear has been created with a laser (laser fired contact, LFC) such that the metal is locally heated and contact is formed. The optimal TPV cell is based on a low doped ( 1 × 10 15 cm - 3 ) p -type germanium substrate having a 500 nm thick n-type emitter ( 1 × 10 19 cm - 3 ) , where front and rear are both passivated with hydrogen rich PECVD amorphous silicon. An AM1.5G record efficiency has been measured for a germanium TPV cell with an LFC rear contact. The application of optical confinement leads to a clear improvement of the spectral response in the wavelength region which is dominant in TPV systems and results in a potential 20% increase of current density compared to the use of a classical germanium photovoltaic cell.

Standalone germanium solar cells are under development for application in high-efficiency mechanically stacked multijunction solar cells and thermophotovoltaic systems. To realize a suitable device, a more fundamental research has been done on germanium doping, surface passivation, and contact formation. In this paper, emitter formation and contact realization are discussed in detail. Emitter formation is done by phosphorous diffusion from a spin-on dopant (SOD) source. Critical parameters are the diffusion time, diffusion temperature, and phosphorous content in the SOD. Front contact formation is done by an innovative method, where the contacting metal is diffused through the amorphous silicon passivation layer. The specific properties of the diffusing metal, diffusion temperature, and diffusion time are important. Using the developed process, a stand-alone germanium solar cell has been realized with a world-class AM1.5G energy conversion efficiency of 7.8%

Passivation of a germanium surface has proved to be challenging. Various materials have been examined for this purpose, like for example silicon nitride and amorphous silicon. In this work the optimisation of PECVD amorphous silicon and the influence of the preliminary surface treatment for passivation purposes are described. Furthermore, experiments done to extract the surface recombination velocity and the bulk lifetime of a germanium substrate will be presented. Optimisation of the deposition parameters, in combination with a pre-deposition in situ hydrogen plasma, results in a surface recombination velocity of 17 cm/s on a lowly doped germanium substrate.

We propose a novel approach to thin-film silicon solar cells, namely the freestanding monocrystalline silicon layer transfer process with heterojunction emitter (FMS-HJ). High crystallographic quality mono-Si films were deposited on freestanding porous silicon (PS) films by chemical vapor deposition (CVD). These free-standing mono-Si (FMS) films were processed into solar cells by creating a-a-Si/c-Si heterojunction. In our preliminary experiments a thin-film FMS-HJ solar cell with 9.6% efficiency was realized in a 20-μμm-thin active layer. Copyright © 2005 John Wiley & Sons, Ltd.

The space charge limited currents J in conducting organic materials often show J∼Vm (where m>2) dependence on voltage V. Two models have been used extensively to understand this behavior. In one model, the mobility μ is assumed to be dependent on electric field F. In the other model, an exponential distribution of traps is assumed and the mobility is taken to be independent of field. In this model the influence of the high electric fields present in organic polymers has not been taken into account. We present a model to calculate the J(V) characteristics for single carrier organic polymers taking into account the change in the occupancy of the traps due to the high electrical fields present in these materials. We show that the field dependent trap occupancy (FDTO) model can effectively explain the current–voltage characteristics reported by several different groups. If the FDTO model is used, it is not necessary to use the two different models mentioned above.

Epitaxial boron-doped emitters by CVD can provide a valuable alternative to the use of aluminum or diffused boron for the creation of p-type emitters. Compared to the traditional boron-diffused emitters for high-efficiency cells, epitaxial emitters need shorter process time, no boron skin removal step and have more opportunities to optimize the emitter doping profile. Our work proves that epitaxial emitters can be a good alternative for the p-type emitter. Very promising cell results with the highest cell efficiency of 17.0% on FZ material with LPCVD emitter and 16.7% on CZ material with APCVD emitter under 1 Sun have been achieved. Good fill factors have been obtained, which indicate good metal contacts are obtained on the epitaxial emitter. Cell results on n-type material are very encouraging and indicate a high potential of such epitaxial emitters for rear junction n-type solar cells.

Epitaxial thin film silicon solar cell technology is one of the most promising midterm alternatives for cost effective industrial solar cell manufacturing. Here, CVD is used to grow the active base layer. However, also the emitter can be grown by CVD, with doping profiles as desired. In this paper, solar cell processes are established integrating both a two-step CVD grown emitter, and state-of-the-art concepts for optical light trapping in epitaxial cells. In this way, the significant increase in Voc is combined with an improved short-circuit and leads to a record efficiency of 16.1% with a current density of 33.2 mA/cm2, approaching the Jsc of bulk silicon solar cells.

Thin-film polysilicon solar cells are a promising low-cost alternative for bulk silicon solar cells due to their reduced material thickness. Recently, we showed that the use of an amorphous silicon/polycrystalline silicon heterojunction emitter instead of a diffused homojunction emitter led to a boost in the open-circuit voltage by 90 mV. Now, we present a full evidence that shows that this improvement is related to the absence of dopant smearing along the grain boundaries. By using scanning spreading resistance microscopy, we found an enlargement of the junction area by a factor of five in case of a homojunction. The tips of the dopant spikes represent lowly doped areas with an enhanced recombination.

Stacks of porous silicon layers have been successfully applied to maximize internal reflection at the interface between a silicon substrate and an epitaxially grown layer. The stack is consist of alternating porous layers of high and low porosity, defined by the quarter-wavelength rule. During the hydrogen bake prior to epitaxial growth of the epitaxial layer, the porous silicon stack crystallizes in the form of thin quasi-monocrystalline silicon layers incorporating large voids. Experimental data of the measured external reflectance have been linked to the internal reflectance. An optical-path-length enhancement factor of seven was calculated in the wavelength range of 900-1200 nm. Application on thin-film epitaxial solar cells showed a 12% increase in short-circuit current and efficiency

The irradiation damage in n/sup +/-Si/p/sup +/-Si/sub 1-x/Ge/sub x/ epitaxial diodes and n/sup +/-Si/p/sup +/-Si/sub 1-x/Ge/sub x//n-Si epitaxial heterojunction bipolar transistors (HBTs) by fast neutrons and MeV electrons is studied as a function of fluence and germanium content for the first time. The degradation of the electrical performance of both diodes and HBTs by irradiation increases with increasing fluence, while it decreases with increasing germanium content. The damage coefficient of reverse current for x=0.12 and 0.16 diodes irradiated by neutrons is calculated to be 6.2/spl times/10/sup -21/ and 5.5/spl times/10/sup -21/ n/sup -1/ A cm/sup 2/, respectively. That of h/sub FE/ for electron-irradiated x=0.08, 0.12 and 0.16 HBTs is 7.6/spl times/10/sup -16/, 2.7/spl times/10/sup -16/ and 1.6/spl times/10/sup -16/ s/sup -1/ cm/sup 2/ respectively. >

The degradation of n/sup +/-Si/p/sup +/-Si/sub 1-x/Ge/sub x/ diodes, which are fabricated on strained Si/sub 1-x/Ge/sub x/ epitaxial layers grown on conventional p-type Si substrates, is investigated through the study of the annealing behaviour of forward and reverse diode current and the electrically active defects induced in the Si/sub 1-x/Ge/sub x/ epitaxial layers. The diodes are irradiated at room temperature with 1-MeV electrons with fluences ranging from 10/sup 14/ to 10/sup 15/ e/cm/sup 2/ in a high voltage transmission electron microscope. The germanium fraction of the Si/sub 1-x/Ge/sub x/ epitaxial layer used for the diodes in this study is x=0.12 and 0.16. The degradation of the diode performance and the presence of deep levels are investigated as a function of electron fluence and germanium content. The degradation of the x=0.12 diodes is more remarkable than that of the x=0.16 diodes. In order to examine the recovery process, isochronal thermal anneals are performed in the temperature range between 100 and 350/spl deg/C. From the annealing behaviour, it is pointed out that the electron capture levels, which are related with interstitial boron, are mainly responsible for the increase of reverse and forward current. >

Theoretical and experimental evidence is presented to show that the effective mass of holes is reduced due to strain in the Ge/sub x/Si/sub 1-x/ layers grown on Si

Irradiation damage in n+‐Si/p+‐Si1−xGex/n‐Si epitaxial diodes and heterojunction bipolar transistors by protons is studied. The degradation of the performance increases with increasing proton fluence, whereas it decreases with increasing germanium content and proton energy. The damage coefficient for proton irradiation is nearly the same as for neutron irradiation and is about three orders of magnitude larger than that for electron irradiation. This difference is due to the different number of knock‐on atoms and the nonionizing energy loss, which is correlated to the difference of mass and the possibility of nuclear collisions.

A rf‐plasma chemical vapor deposition process for selective epitaxial Si growth from SiH4 and SiF4 at a deposition temperature of 300–400 °C is described. Selective epitaxial growth is obtained as a balance of deposition precursors versus etching by F species. Also, the results indicate that a high H‐surface coverage is not essential to deposit crystalline Si films by very low temperature rf‐plasma chemical vapor deposition. P‐doped films with a mobility of 80 cm2/V s and a carrier concentration of 3×1018 cm−3 are reported.

In recent years, research on epitaxial growth for thin film crystalline silicon solar cells has gained in importance due to the alarming feedstock shortage of electronic grade polysilicon. This work concentrates on the epitaxial growth of the emitter, as a replacement for emitter diffusion, on top of an epitaxially grown base. The main advantage of emitter formation by CVD is more controllable doping profile, which gives the opportunity to form an excellent front surface field, leading to high open-circuit voltages. In this paper, the doping profile and thickness of the epitaxial layers are optimized. A solar cell process including a light trapping mechanism resulted in solar cell efficiencies close to 15%.

We report on the physical, electrical, and optical properties of Cu2ZnSnSe4 (CZTSe) solar cells based on an absorber layer fabricated by selenization of sputtered Cu, Zn, Sn multilayers. It is shown that the doping density as measured by drive level capacitance profiling is correlated exponentially to the Zn/Sn ratio of the CZTSe absorber as measured by energy dispersive X-ray spectroscopy. Furthermore, it is shown that the open circuit voltage of the cells, minority carrier lifetime, and peak position of the photoluminescence response of the absorber all correlate with the doping level and, therefore, with the Zn/Sn ratio measured in the absorber. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4775366] We would like to acknowledge Tom De Geyter, Greetje Godiers, and Guido Huyberechts from Flamac in Gent for sputtering of the metal layers. AGC is acknowledged for providing substrates. The Flemish “Strategisch Initiatief Materialen” (SIM) SoPPoM program is acknowledged for their collaboration. Hamamatsu Photonics is acknowledged for providing the time resolved photoluminescence measurement system.

Thin film crystalline Si solar cells on cheap Si-based substrates have a large potential in PV technology. Optical light confinement is a very crucial point of such thin film structures. Porous Si (PS) as a perfect light diffuser could be used as a backside reflector if its multi-layer structure would be preserved during the deposition of a thin Si film. That is why low-energy plasma enhanced chemical vapor deposition (LEPECVD) is chosen to deposit a thin Si film on a PS multilayer structure at low temperature and a high deposition rate. This technique allows one to deposit a Si film with an epitaxial quality on the top of PS without destroying its multilayer structure as revealed by high-resolution X-ray diffraction and cross-sectional transmission electron microscopy (TEM). The epilayers of 10 μm are grown at very high deposition rate (around 3 nm/s) at 590°C. TEM-analysis reveals that during the deposition a high density of defects forms at the interface PS/epi-Si and spreads through the whole epilayer. The defect density is decreased when the deposition temperature is increased to 645°C. LEPECVD appears to be an appropriate deposition technique to grow thin Si films on cheap Si based substrates with PS reflector.

This work focuses on using copper (Cu) as the main conductor as an alternative to standard screen printed silver (Ag) front contacts for homogeneous emitter silicon solar cells. Two different approaches to form Cu plated contacts based on laser ablation of the SiNx:H antireflection coating (ARC) and subsequent plating steps are presented. In the first approach, contacts are formed by Ni/Cu/Ag plating in an industrial in-line plating tool and subsequent rapid thermal annealing (RTA). In the second approach, the RTA step is performed after sputtering of a thin nickel layer and prior to the final Ni/Cu/Ag plating sequence. Using the latter approach, results are presented on large area 12.5×12.5 cm2 p-type CZ-Si PERC-type solar cells featuring an advanced 120 Ω/sq homogeneous emitter and local Al contacts on the rear surface accompanied by a SiOx/SiNx rear side passivation stack. Solar cell efficiencies of up to η=19.6% and average pull tab adhesion results >2 N are reported.

Epitaxial growth of phosphorus‐doped silicon deposited at 250 °C from a radio‐frequency glow discharge from SiH4 is demonstrated by high‐resolution electron microscopy (HREM) and spreading resistance profile measurements. Thin epitaxial films are present at the interface between (100) Si substrates and hydrogenated amorphous silicon. After recrystallization at 700 °C, single‐crystal layers are obtained, in which HREM reveals extensive twinning. The fact that epitaxial growth can take place at 250 °C in a system with a background pressure of only 5×10−6 mbar can be attributed to the presence of species in the SiH4 plasma that reduce the native oxide and the use of HF in the cleaning procedure.

L'urine recueillie apres effort physique intense contient l'haptoglobine de type 2-1 sous une forme proche de sa structure complete. Les cinq bandes les plus anodiques sont visibles dans l'urine d'effort, quoiqu'a un taux inferieur a celui d'un serum normal.

Doping of TiO 2 – a wide band gap material - with Neodymium (Nd 3+ ) ions have been the focus of research interest for the solar spectrum downshifting, a process which can improve the efficiency of silicon based solar cells. This work presents the influence of varying Nd doping concentration in the range 1.17-25 at.% in the TiO 2 host matrix. Thin films of thickness between 1 - 2 μm were deposited by Radio-Frequency Co-Sputtering of TiO 2 and Neodymium (Nd) target on quartz and silicon substrates at room temperature. The films are annealed in an air ambient after deposition. Film properties were studied from the structural and chemical composition point of view by means of X-ray diffraction (XRD), Auger Electron Spectroscopy (AES). Two distinct photoluminescence emission peaks were observed at 902 and 1080 nm in the doped films, pertaining to the transitions between the excited levels 4 F 3/2 to 4 I 9/2 and 4 I 11/2 levels of the Nd 3+ ions by exciting at 514.5 and 355 nm.