Thoughts about a General Theory of Influence in a DIME/PMESII/ASCOP/IRC2 Model

The leading question of this paper is: “How would influence warfare (“iWar”) work and how can we simulate it?” The paper discusses foundational aspects of a theory and model of influence warfare by discussing a framework built along the DIME/PMESII/ASCOP dimension forming a prism with three axes. The DIME concept groups the many instruments of power a nation state can muster into four categories: Diplomacy, Information, Military and Economy. PMESII describes the operational environment in six domains: Political, Military, Economic, Social, Information and Infrastructure. ASCOPE is used in counter insurgency (COIN) environments to analyze the cultural and human environment (aka the “human terrain”) and encompasses Areas, Structures, Capabilities, Organization, People and Events. In addition, the model reflects about aspects of information collection requirements (ICR) and information capabilities requirements (ICR) - hence DIME/PMESII/ASCOP/ICR2. This model was developed from an influence wargame that was conducted in October 2018. This paper introduces basic methodical questions around model building in general and puts a special focus on building a framework for the problem space of influence/information/hybrid warfare takes its shape in. The article tries to describe mechanisms and principles in the information/influence space using cross discipline terminology (e.g. physics, chemistry and literature). On a more advanced level this article contributes to the Human, Social, Culture, Behavior (HSCB) models and community. One goal is to establish an academic, multinational and whole of government influence wargamer community. This paper introduces the idea of the perception field understood as a molecule of a story or narrative that influences an observer. This molecule can be drawn as a selection of vectors that can be built inside the DIME/PMESII/ASCOP prism. Each vector can be influenced by a shielding or shaping action. These ideas were explored in this influence wargame

In vacuo XPS investigation of Cu In,Ga Se2 surface after RbF post deposition treatment

Latest record efficiencies of Cu In,Ga Se2 CIGSe solar cells were achieved by means of a rubidium fluoride RbF post deposition treatment PDT . To understand the effect of the RbF PDT on the surface chemistry of CIGSe and its interaction with sodium that is generally present in the CIGSe absorber, we performed an X ray photoelectron spectroscopy XPS study on CIGSe thin films as deposited by a three stage co evaporation process and after the consecutive RbF PDT. The sample transfer from the deposition to the XPS analysis chamber was performed via an ultra high vacuum transfer system. This allows to minimize air exposure, avoiding oxide formation on the CIGSe surface, especially for alkali treated absorbers. Beside an expected reduction of Cu and Ga content at the surface of RbF treated CIGSe films, we find that Rb penetrates the CIGSe and, contrary to fluorine, it is not completely removed by subsequent ammonia etching. The remaining Rb contribution at 110.0 amp; 8239;eV binding energy, which appears after the RbF PDT is similar to the one detected on a co evaporated RbInSe2 reference sample and together with a new Se 3d contribution may hence belong to an Rb In Se secondary phase on the CIGSe surface. In addition, Na is driven towards the surface of the CIGSe absorber as a direct result of the RbF PDT. This proves the ion exchange mechanism in the absence of moisture and air oxygen between heavy Rb atoms incorporated via PDT and lighter Na atoms supplied by the glass substrate. A remaining XPS signal of Na 1 amp; 8239;s is observed after etching the vacuum transferred RbF CIGSe sample, indicating that Rb and or F are not as much a driving force for Na as oxygen usually i

Effect of Na and the back contact on Cu2Zn(Sn,Ge)Se4 thin-film solar cells : towards semi-transparent solar cells

Cu2ZnSn1-xGexSe4 (CZTGSe) thin films have been grown onto Mo/SLG and Mo/V2O5/FTO/SLG substrates using thermal co-evaporation followed by a subsequent thermal annealing. A NaF precursor layer was evaporated prior to the deposition of the kesterite absorber layer. In the samples grown on Mo/SLG, it has been found that Na promotes Ge incorporation into the Cu2ZnSnSe4 lattice. The high concentration of incorporated Ge leads to the segregation of Sn-Se secondar y phases as we l l as to an accumulation of Sn next to the Mo layer. The use of 12 and 16 nm NaF thick precursor layers prior to the CZTGSe deposition leads to absorber band gaps of 1.30 and 1.34 eV, and to device performances of 4.7 and 4.0%, respectively. A higher Na content, furthermore, caused the formation of bigger grains, a higher charge carrier concentration and a shorter depletion width. A 12 nm NaF precursor layer was used for the devices grown on FTO-based substrates, producing an optimal back contact that allows achieving efficiencies of 5.6% and transmittance of 30% in the near infrared range. This enhanced performance can be associated with the absence of secondary phases and Ge distribution through the absorber layer. The formation of a MoSe2 layer at the back interface in al l the investigated devices seems to play a crucial role to improve the solar cell efficiency

Routes to develop a [S]/([S]+[Se]) gradient in wide band-gap Cu2ZnGe(S,Se)4 thin-film solar cells

Wide band-gap kesterite-based solar cells are very attractive to be used for tandem devices as well as for semi-transparent photovoltaic cells. Here, Cu2ZnGe(S,Se)4 (CZGSSe) thin films have been grown by sulfurization of co-evaporated Cu2ZnGeSe4. The influence of a NaF precursor layer and of a Se capping film on CZGSSe absorbers and solar cells has been investigated. It has been found that the distribution of [S]/([S]+[Se]) through the CZGSSe absorber layer is strongly dependent on the Na content. Na promotes the diffusion of S towards the bulk of the absorber layer. Thicker NaF layers>6 nm lead to a higher S content in the bulk of the absorber layer, but to a decreased accumulation of sulphur at the surface, as detected by GIXRD, GD-OES, and Raman spectroscopy measurements. A relationship between Jsc, FF and Na-content supplied was found; higher Na content resulted in improved solar cell efficiencies. It has also been possible to modify the [S]/([S]+[Se])-gradient throughout the CZGSSe film by the absence of the Se capping layer, achieving devices with 2.7% performance and Eg = 2.0 eV. This work reveals two ways to control the [S]/([S]+[Se]) depth-profile to produce wide band gap CZGSSe absorber layers for efficient solar cells

Effects of KF and RbF post deposition treatments on the growth of the CdS buffer layer on CIGS thin films a comparative study

In this contribution we are analyzing and comparing the impact of two different alkali fluorine post deposition treatments KF and RbF on the growth of chemical bath deposited CdS buffer layers on Cu In, Ga Se2 absorber layers for thin film solar cells. By combining Raman scattering, scanning electron microscopy, current voltage analysis and measurements of the internal quantum efficiency we provide a comprehensive picture of this issue on the material and device level. We find that both PDTs lead to a better CdS coverage of the surface of the CIGS, which leads to an improved junction quality at early growth stages compared to untreated devices. Furthermore the growth rate of the CdS is enhanced on KF treated absorber layers while it is decreased on those treated with RbF compared to the reference . This leads to a more stable behavior of RbF treated devices after longer duration of the CdS deposition, while the KF treated devices suffer from reduced fill factor and open circuit voltage. Furthermore we show that not only both PDTs but also the growth of the CdS lead to a reduction of the amount of the so called ordered defect compound, which is initially present at the surface of our absorber layers. This behavior indicates either the formation of CdCu anti sites or of a secondary phase at the interfac

Decay mechanisms in CdS buffered Cu In,Ga Se2 thin film solar cells after exposure to thermal stress Understanding the role of Na

Due to their tunable bandgap energy, Cu In,Ga Se2 CIGSe thin film solar cells are an attractive option for use as bottom devices in tandem configurations. In monolithic tandem devices, the thermal stability of the bottom device is paramount for reliable application. Ideally, it will permit the processing of a top device at the required optimum process temperature. Here, we investigate the degradation behavior of chemical bath deposited CBD CdS buffered CIGSe thin film solar cells with and without Na incorporation under thermal stress in ambient air and vacuum with the aim to gain a more detailed understanding of their degradation mechanisms. For the devices studied, we observe severe degradation after annealing at 300 C independent of the atmosphere. The electrical and compositional properties of the samples before and after a defined application of thermal stress are studied. In good agreement with literature reports, we find pronounced Cd diffusion into the CIGS absorber layer. In addition, for Na containing samples, the observed degradation can be mainly explained by the formation of Na induced acceptor states in the TCO front contact and a back contact barrier formation due to the out diffusion of Na. Supported by numerical device simulation using SCAPS 1D, various possible degradation models are discussed and correlated with our finding

Realizing Double Graded CIGSe Absorbers with the R2R Hybrid CIGSe Process

This article presents an approach for industrial roll to roll R2R deposition of Cu In,Ga Se2 CIGSe thin films on stainless steel foil for use as absorber layers in flexible thin film solar cells. The hybrid CIGSe deposition process combines magnetron sputtering with evaporation techniques and allows the realization of a double graded CIGSe layer, reaching a conversion efficiency of currently up to 14.0 w o antireflective coating . The influence of different power settings of the individual magnetrons on the gallium profile is described. For a deeper understanding of differences between a static and an R2R process, a calculated flux diagram is presented. In the second part of this contribution, the homogeneity of the industrial scale samples is discussed by comparing the change in CGI and GGI over the foil width of 30 cm. The hybrid CIGSe deposition process excels in a straightforward scalability for industrial usage due to the application of planar magnetron sputtering sources as metal vapor suppl

Glow discharge optical emission spectrometry for quantitative depth profiling of CIGS thin films

Determining elemental distributions dependent on the thickness of a sample is of utmost importance for process optimization in different fields e.g. from quality control in the steel industry to controlling doping profiles in semiconductor labs. Glow discharge optical emission spectrometry GD OES is a widely used tool for fast measurements of depth profiles. In order to be able to draw profound conclusions from GD OES profiles, one has to optimize the measurement conditions for the given application as well as to ensure the suitability of the used emission lines. Furthermore a quantification algorithm has to be implemented to convert the measured properties intensity of the emission lines versus sputtering time to more useful parameters, e.g. the molar fractions versus sample depth depth profiles . In this contribution a typical optimization procedure of the sputtering parameters is adapted to the case of polycrystalline Cu In,Ga S,Se 2 thin films, which are used as absorber layers in solar cell devices, for the first time. All emission lines used are shown to be suitable for the quantification of the depth profiles and a quantification routine based on the assumption of constant emission yield is used. The accuracy of this quantification method is demonstrated on the basis of several examples. The bandgap energy profile of the compound semiconductor, as determined by the elemental distributions, is compared to optical measurements. The depth profiles of Na the main dopant in these compounds are correlated with measurements of the open circuit voltage of the corresponding devices, and the quantification of the sample depth is validated by comparison with profilometry and X ray fluorescence measurement

Perovskite CIGS Tandem Solar Cells From Certified 24.2 toward 30 and Beyond

We demonstrate a monolithic perovskite CIGS tandem solar cell with a certified power conversion efficiency PCE of 24.2 . The tandem solar cell still exhibits photocurrent mismatch between the subcells; thus optical simulations are used to determine the optimal device stack. Results reveal a high optical potential with the optimized device reaching a short circuit current density of 19.9 mA cm 2 and 32 PCE based on semiempirical material properties. To evaluate its energy yield, we first determine the CIGS temperature coefficient, which is at amp; 8722;0.38 K 1 notably higher than the one from the perovskite subcell amp; 8722;0.22 K 1 , favoring perovskite in the field operation at elevated cell temperatures. Both single junction cells, however, are significantly outperformed by the combined tandem device. The enhancement in energy output is more than 50 in the case of CIGS single junction device. The results demonstrate the high potential of perovskite CIGS tandem solar cells, for which we describe optical guidelines toward 30 PC