Secondary Ion Mass Spectrometry Experiments Research Articles

Unlocking the Potential of Liquid Plasma Polymer Films: Characterizing Aging Effects and Their Impact on the Wrinkling Phenomenon.

Here, we present the study of the intricate dynamics between the physicochemical properties of liquid propanethiol plasma polymer films (PPFs) and the formation of wrinkles in PPF/Al bilayers. The study investigates the effect of liquid PPF aging in the air before top Al layer deposition by magnetron sputtering on the wrinkling phenomenon for 4 days. Thanks to atomic force microscopy, the wrinkle dimensions were found to decrease by approximately 55% in amplitude and 66% in wavelength, correlated with an increase in the viscosity of the PPF over the aging duration (i.e., from less than 107 to 1010 Pa·s). This behavior is not linked to alterations in cross-linking degree as evidenced by time-of-flight secondary ion mass spectrometry experiments but rather to network densification driven by the inherent molecular chain mobility due to the viscous state of the PPF. X-ray photoelectron spectroscopy measurements emphasizing the absence of oxidation of the PPF over the aging duration support this, revealing a unique aging mechanism distinct from other plasma polymer families. Overall, this study offers valuable insights into the design and application of mechanically responsive PPFs involved in bilayer systems, paving the way for advancements in nanotechnology and related fields.

Unlocking the Potential of Liquid Plasma Polymer Films: Characterizing Aging Effects and Their Impact on the Wrinkling Phenomenon.

Here, we present the study of the intricate dynamics between the physicochemical properties of liquid propanethiol plasma polymer films (PPFs) and the formation of wrinkles in PPF/Al bilayers. The study investigates the effect of liquid PPF aging in the air before top Al layer deposition by magnetron sputtering on the wrinkling phenomenon for 4 days. Thanks to atomic force microscopy, the wrinkle dimensions were found to decrease by approximately 55% in amplitude and 66% in wavelength, correlated with an increase in the viscosity of the PPF over the aging duration (i.e., from less than 107 to 1010 Pa·s). This behavior is not linked to alterations in cross-linking degree as evidenced by time-of-flight secondary ion mass spectrometry experiments but rather to network densification driven by the inherent molecular chain mobility due to the viscous state of the PPF. X-ray photoelectron spectroscopy measurements emphasizing the absence of oxidation of the PPF over the aging duration support this, revealing a unique aging mechanism distinct from other plasma polymer families. Overall, this study offers valuable insights into the design and application of mechanically responsive PPFs involved in bilayer systems, paving the way for advancements in nanotechnology and related fields.

Alkali-metal-based molecular-ion secondary ion mass spectrometry for precise quantitative analysis of low-dimensional materials without standards

Advancement in the understanding of fundamental aspects of Secondary Ion Mass Spectrometry (SIMS) has made this technique to be extremely powerful for quantitative materials analysis. The secondary ion emission process is a complex phenomenon involving various mechanisms to understand the mechanism. Among the existing mechanisms, the “electron-tunneling model” is the most accepted concept in the understanding of ionization probability for positive and negative ions. This model essentially concerns the survival probability of an ion emitted from the surface. As the intensity of secondary ions of a certain element depends strongly on the efficiency of ionization of a sputtered atom or molecule, the “local surface chemistry” plays a significant role in the secondary ion emission. This is purported as the “Matrix Effect” in SIMS, making the technique extremely challenging for quantification of materials in spite of the fact that it has the highest detection sensitivity (<ppb) and exceptional depth-resolution (<1[Formula: see text]nm). Therefore, it is required to correct the “matrix effect” for quantitative analysis. If the probing element (M) in its close proximity sees an alkali element (such as Li, Rb, K, Na and Cs, referred to as “A”) on the sample surface, the sputtered neutral atom (M0) of the probing element can attach an alkali-ion forming a quasi-molecular (MA)[Formula: see text] ion. Such a phenomenon can also occur if an alkali ion beam is chosen as the primary beam for sputtering. The MA[Formula: see text] molecular ion formation is directly related to the atomic polarizability of the element M. Since the sputtering of neutral atom (M0) is unconnected with the formation of MA[Formula: see text] ion, the “matrix effect” decreases dramatically in the analysis using MA[Formula: see text] ions. The phenomenon is very similar to the mechanism of “secondary neutral mass spectrometry” (SNMS). Although these (MA)[Formula: see text] molecular ions are potentially applicable in the direct quantification of materials without the need for “calibration standards”, it generally has a weak intensity. In such a case, the (MA)[Formula: see text] molecular ions are preferred in the analysis because of their higher detection sensitivity (by a few orders of magnitude in some cases), compared to that of (MA)[Formula: see text] molecular ions. Monitoring of the molecular ions is routinely preferred in conventional SIMS experiments to discriminate the sputtered ion species which are affected by mass interference or have poor dynamic ranges. For example, while making the SIMS analysis of GaAs, carbon as an impurity element is detected by monitoring (AsC)[Formula: see text] molecular ions instead of C− ions, because the C− ions have high background arising from the carbon-containing residual-gas species in the analysis chamber. Caesium is decidedly chosen for MCs[Formula: see text] or MCs[Formula: see text] molecular ions in SIMS because of the strongest reactivity and electropositive nature of caesium. This paper deals with a comprehensive discussion on the ion-emission phenomena in sputtering, the “matrix effect” and its compensation, and the potential application of the “MCs[Formula: see text]-SIMS” ([Formula: see text]) in the effective quantitative chemical analysis of materials. A special prominence has been given to the quantification of low-dimensional materials, superlattices and quantum-confined structures using this state-of-the-art “MCs[Formula: see text]-SIMS” approach in all complexities.

Empirical indication for desalinating properties of porous boron nitride

In recent years, inorganic 2D materials have been recognized as promising candidates for membrane filtration. In particular, theoretical studies predict the excellent desalination performance of nanoporous hexagonal boron nitride. However, studies showing the experimental realization of such systems are to this date missing. In this work, we demonstrate the desalinating properties of sp2-bonded boron nitride. Secondary Ion Mass Spectrometry experiments have shown the clear separation of NaCl and water by the boron nitride film: Na and Cl ions have been retained and trapped in the near-surface region, while water permeated through its whole depth. Analysis based on the diffusion equation revealed that the diffusion coefficient of water is over 3 orders of magnitude higher than the diffusion coefficient of NaCl in the temperature range of 25-65°C, manifesting that boron nitride is a material of high potential for use as a selective layer for membrane filtration.

A Microscopic View of Macromolecule Transfer in the Vacuum Using Gas and Bismuth Clusters

Transferring large nonvolatile molecules in the vacuum is key to both their characterization by mass spectrometry (ion mobility, etc.) and their use as nanofabrication building blocks in soft-landing-type experiments. Recently, our group performed the successful transfer and redeposition of intact and bioactive lysozyme (14 kDa) with large gas cluster ion beams, in the absence of a solvent or matrix, demonstrating that such beams could serve as tools for macromolecule manipulation. A number of fundamental questions arose in relation with this experimental proof-of-concept, concerning for instance the maximum molecular size for successful transfer, the effect of the cluster projectile incidence angle, the dependence of molecular dissociation on the projectile energy and size, the internal energy uptake ultimately leading to metastable decay reactions, or the influence of the surface interactions on desorption. To address these questions, a series of molecular dynamics simulations were conducted involving cluster impacts on an adsorbed globular polystyrene (PS) macromolecule of 60 kDa, with a mass and shape comparable to those of a protein such as bovine serum albumin. Conditions of intact desorption of this PS molecule by Ar clusters are identified, in terms of energy per atom and incidence angle, and the results are compared to 30 keV Bi5 impacts, commonly used for molecular analysis and 2D imaging in our time-of-flight secondary ion mass spectrometry experiments. When Ar cluster impact conditions are appropriate for intact desorption, the take-off angle of the macromolecule is larger than the projectile incidence. Bombardment by a massive methane projectile (6.6 × 104 methane molecules) does not induce qualitatively different results, and in general, the energy per atom or energy per unit mass remains the deciding factor concerning the survival or dissociation of the bombarded molecule. In contrast with large gas clusters, Bi5 projectiles largely fail at desorbing the intact macromolecules, because of the detrimental effect of the collision cascade and the insufficient momentum transferred by the crater expansion for molecular lift off. Additionally, 10 keV Ar5000 projectiles with 45–75° incidence with respect to the surface normal directly transfer momentum to the macromolecule via their backscattered Ar atoms and small clusters, inducing molecular desorption with center-of-mass velocities of the order of 1 km/s. The implications for future experiments are discussed.

Combining SIMS and mechanistic modelling to reveal nutrient kinetics in an algal-bacterial mutualism.

Microbial communities are of considerable significance for biogeochemical processes, for the health of both animals and plants, and for biotechnological purposes. A key feature of microbial interactions is the exchange of nutrients between cells. Isotope labelling followed by analysis with secondary ion mass spectrometry (SIMS) can identify nutrient fluxes and heterogeneity of substrate utilisation on a single cell level. Here we present a novel approach that combines SIMS experiments with mechanistic modelling to reveal otherwise inaccessible nutrient kinetics. The method is applied to study the onset of a synthetic mutualistic partnership between a vitamin B12-dependent mutant of the alga Chlamydomonas reinhardtii and the B12-producing, heterotrophic bacterium Mesorhizobium japonicum, which is supported by algal photosynthesis. Results suggest that an initial pool of fixed carbon delays the onset of mutualistic cross-feeding; significantly, our approach allows the first quantification of this expected delay. Our method is widely applicable to other microbial systems, and will contribute to furthering a mechanistic understanding of microbial interactions.

Direct Analysis of Ion-Induced Peptide Fragmentation in Secondary-Ion Mass Spectrometry.

Primary-ion-induced fragmentation in organic molecules can strongly influence the results in secondary-ion mass spectrometry (SIMS) of organic and biomolecular samples. In order to characterize this ion-induced fragmentation, oligopeptide samples irradiated in SIMS experiments were investigated by means of desorption/ionization induced by neutral SO2 clusters (DINeC). The latter is a nondestructive desorption method for mass spectrometry of biomolecules, which gives direct access to the fragments induced in the sample. Comparison of TOF-SIMS and DINeC mass spectra revealed qualitative differences between the fragments, which remain in the sample and the fragments sputtered during ion bombardment. The fragmentation strength and its spatial distribution were found to be quantitatively different for Bi1+, Bi3+, and Ar1000+ primary ions, leading to different distributions of the degree of fragmentation in the samples as directly measured by means of DINeC depth profiles.

A Correlative ToF-SIMS/SPM Methodology for Probing 3D Devices.

With the continuous miniaturization and increasing complexity of the devices used in nanotechnology, there is a pressing need for characterization techniques with nm-scale 3D-spatial resolution. Unfortunately, techniques like Secondary Ion Mass Spectrometry (SIMS) fail to reach the required lateral resolution. For this reason, new concepts and approaches, including the combination of different complementary techniques, have been developed in over the past years to try to overcome some of the challenges. Beyond the problem of spatial resolution in a 3D SIMS experiment, one is also faced with the impact of changes in topography during the analysis. These are quite difficult to identify because they originate from the different sputter rates of the various materials and or phases in a heterogeneous system and are notorious at the interfaces between organic and inorganic layers. As each of these materials will erode at a different velocity, accurate 3D-analysis will require means to establish a spatially resolved relation between ion bombardment time and depth. Inevitably such a nonhomogeneous erosion will lead to the development of surface topography. The impact of these effects can be overcome provided one can capture the time and spatially dependent surface erosion (velocity) with high spatial resolution during the course of a profiling experiment. Incorporating a Scanning Probe Microscope (SPM) unit which provides topography measurements with high spatial resolution, into a SIMS tool (e.g., Time of Flight (ToF) SIMS) with means to alternate between SPM and SIMS measurements, is one approach to meet that demand for complementary topographical information allowing accurate 3D chemical imaging. In this paper, the result of integrating a SPM module into a ToF-SIMS system is presented illustrating the improvements in 3D data accuracy which can be obtained when analyzing complex 3D-systems.

The Energy State of Epitaxial Layers in a Multilayer Heterostructure, Grown on a (001)GaAs Substrate

It is shown based on the structural analysis by reciprocal space mapping and the experimental secondary ion mass spectrometry and transmission electron microscopy data that, along with lateral compressive stress, vertical compressive stress is induced in a multilayer epitaxial heterostructure with a metamorphic step-graded buffer. The reason for this stress is that interphase boundaries hinder complete stress removal at strain relaxation. The analysis carried out within the linear elasticity theory showed that the elastically strained state of the heterostructure layers is similar to the state arising during a two-stage deformation process (bulk and biaxial compression). It is shown that the free energy of the system in the metastable state is minimal in this case.

TOF-SIMS Analysis Using Bi3 + as Primary Ions on Au Nanoparticles Supported by SiO2/Si: Providing Insight into Metal-Support Interactions.

Au nanoparticles with a mean diameter of 20 nm with a coverage of ∼20% of the surface were distributed on a Si wafer surface and studied both before and after being annealed (at 100 and 300 °C). The two types of samples were analyzed using secondary ion mass spectroscopy (SIMS) with Bi3+ clusters as the primary ions combined with surface etching using Ar1000+ clusters. We observed a substantial difference in the SIMS spectra combined with a relatively short sputtering time of Ar1000+. In the nonannealed samples, bare Au cluster cations and Si+ were observed in the SIMS spectra; AuSi+ clusters were also observed in the annealed samples. These results indicate Au-silicide formation at a part of the periphery of the Au nanoparticles upon annealing. We suggest that SIMS experiments using cluster ions such as Bi3+ can not only be used for surface elemental analyses but also provide information on local chemical environments of elements on the surface. This is an important issue in heterogeneous catalysis (e.g., strong metal–support interactions). We also advise that one should be careful interpreting the SIMS data combined with a longer Ar1000+ sputtering time because this can deteriorate the surfaces from their original structures.

Adsorption performance of copper ions on arsenopyrite surfaces and implications for flotation

Abstract The removal of arsenic from base-metal ores is an important environmental objective, especially in relation to mineral processing. Herein, we report an investigation into the adsorption performance of copper ions on arsenopyrite surfaces and implications for flotation using local electrochemical impedance and X-ray photoelectron spectroscopies, time-of-flight secondary ion mass spectrometry, zeta-potential measurements, and microflotation experiments. We show that the electrochemical impedance and degree of oxidation of the arsenopyrite decreases as Cu2+ is adsorbed onto the arsenopyrite surface, and copper species remain on the surface in the form of Cu(I) following treatment with Cu2+, while Cu2+ improves the surface charge of the arsenopyrite. A heterogeneously distributed Cu signal appears in the X-ray photoelectron spectrum of the arsenopyrite sample treated with Cu2+ ions, and copper in the form of copper sulfide remains on the mineral surface. Microflotation experiments reveal that the low floatability of arsenopyrite in alkaline environments is improved by treatment with Cu2+.

Ionization probability of sputtered indium under irradiation with 20-keV fullerene and argon gas cluster projectiles

The formation probability of secondary ions released from a metal surface under bombardment with a 20-keV cluster ion beam is investigated using combined time-of-flight secondary ion and neutral mass spectrometry (Tof-SIMS/SNMS) experiments. The emitted neutral atoms and clusters are post-ionized after their ejection using strong-field photoionization in an intense short infrared laser pulse. Comparing the secondary ion signal with that of the corresponding neutral particles, the ionization probability of sputtered indium atoms and Inn clusters with n = 2–4 is determined. The results are compared between two different projectile cluster ions, namely i) C60+ and ii) Arn+ with n∼1000. It is shown that the ionization probability obtained with the fullerene cluster is by roughly a factor 4 larger than that obtained with the rare gas cluster, thereby indicating that there is no nonlinear enhancement of the transient electronic excitation generated by a cluster impact.

Molecular SIMS Ionization Probability Studied with Laser Postionization: Influence of the Projectile Cluster

The formation probability of (quasi-)molecular secondary ions released from an organic film under bombardment with a 20 keV cluster ion beam is investigated using combined time-of-flight secondary ion and neutral mass spectrometry (ToF-SIMS/SNMS) experiments. The emitted neutral molecules are postionized after their ejection using strong-field photoionization in an intense short infrared laser pulse. Comparing the (quasi)-molecular secondary ion signal with that of the corresponding neutral molecules, the ionization probability of sputtered intact coronene and guanine molecules is determined. The results are compared between two different projectile cluster ions, namely (i) C60+ and (ii) Arn+ with n ∼ 1000. It is shown that both projectiles deliver different SNMS spectra, indicating pronounced differences in the collision-induced fragmentation of the emitted molecules. For guanine, the ionization probability obtained with both projectiles is of the same order of magnitude (∼10–3), with the fullerene cluster producing a slightly larger ionization efficiency than the rare gas cluster. For coronene, on the other hand, a substantially lower ionization efficiency is found for the gas cluster projectile.

Cluster ion beam generation from a wetted needle emitter for organic secondary ion mass spectrometry (organic SIMS) using a protic ionic liquid, propylammonium nitrate.

Propylammonium nitrate (PAN, [C3 H7 NH3 ][NO3 ]), a protic ionic liquid, has an active proton in its molecular structure, so that it can promote protonation. In addition, PAN has high aggregability, so that it tends to form large aggregated (or cluster) ions. These features will be desirable for cluster ion beams in secondary ion mass spectrometry (SIMS) of organic materials. The aggregability may enable us to generate a cluster ion beam from a needle tip wetted with PAN by electrospray in vacuum. For these reasons, cluster ion beam generation was investigated using an externally wetted needle emitter. A sharpened glass rod was used as a needle emitter. PAN was electrosprayed in vacuum using the needle emitter to generate a cluster ion beam. Beam characteristics were investigated with an apparatus for measuring transient responses of a beam current. SIMS experiments were also performed using the cluster ion beam as a primary ion beam; arginine and polyethylene glycol (PEG300) were analyzed. A stable cluster ion beam was generated from the needle emitter wetted with PAN. The ion beam consisted of mixed cluster ions whose m/z ranged from about 180 to 5000 or higher. The cluster ion beam successfully produced protonated molecules [M + H]+ (M denotes arginine and PEG molecules) with relatively little fragmentation. Adduct ions [M + C3 H7 NH3 ]+ formed by propylammonium-attachment reaction were also detected for PEG. It has been demonstrated that a needle emitter wetted with PAN can generate a cluster ion beam that includes massive cluster ions. The cluster ion beam proved to be helpful in producing molecular secondary ions and suitable for a primary ion beam in organic SIMS.

Molecular ionization probability in cluster-SIMS

The ionization efficiency of molecular species sputtered under bombardment with cluster ion beams is generally assumed to be rather low, but hard experimental evidence for this notion is still lacking. In order to estimate the prospects for possible sensitivity improvements in molecular secondary ion mass spectrometry (SIMS) experiments, the author therefore reports on recent experiments utilizing laser postionization (LPI) in order to determine an absolute ionization probability value for a few organic molecules sputtered under C60 cluster ion bombardment. The results show that the molecular ionization efficiency obtained under these bombarding conditions is of the order of 10−3, leaving at least 2 orders of magnitude for possible enhancement of the physical or a chemical ionization mechanism leading to the formation of (quasi-) molecular secondary ions. Analyzing the measured molecular LPI signal, the author demonstrates that about the same headroom exists for improvement of the currently achieved postionization efficiency. Using trehalose as a model system, the author then illustrates the level of improvement achieved by different attempts to utilize projectile induced surface chemistry in order to enhance the ionization efficiency. The results may be useful to guide new developments aimed at enhancing the detection sensitivity in molecular cluster-SIMS experiments.

Time-of-flight secondary ion mass spectrometry using a new primary ion beam generated by vacuum electrospray of a protic ionic liquid, propylammonium nitrate.

Protic ionic liquids have the potential to be useful materials for primary ion beams in terms of protonation, since they have active protons. Selecting protic ionic liquids suitable for primary ion beams is of great importance to increase molecular secondary ion yields. Propylammonium nitrate ([C3 H7 NH3 ][NO3 ]) seems promising in view of its proton affinity. It is likely that [C3 H7 NH3 ]+ cations can act as proton donors, and [NO3 ]- anions can work as proton acceptors. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) experiments have been performed to verify the usefulness of [C3 H7 NH3 ][NO3 ]. A primary propylammonium nitrate cluster ion beam was generated by vacuum electrospray, and then used to analyze amino acids (arginine, glutamic acid, aspartic acid), angiotensin II and polyethylene glycol. Positive and negative secondary ion mass spectra were obtained to study both protonation and deprotonation. The propylammonium nitrate cluster ion beam successfully generated protonated molecules [M+H]+ of all the analytes in positive ion mode. The primary ion beam also generated deprotonated molecules [M-H]- of glutamic acid, aspartic acid and angiotensin II in negative ion mode. Additionally, adduct ions related to [C3 H7 NH3 ][NO3 ] were detected in the case of arginine and polyethylene glycol. The TOF-SIMS experiments confirmed that the propylammonium nitrate cluster ion beam was useful in generating molecular secondary ions, demonstrating that it is well suited for a primary ion beam in TOF-SIMS.

Ionization Probability in Molecular Secondary Ion Mass Spectrometry: Protonation Efficiency of Sputtered Guanine Molecules Studied by Laser Postionization

The prospect of improved secondary ion yields for secondary ion mass spectrometry (SIMS) experiments drives innovation of new primary ion sources, instrumentation, and postionization techniques. An important factor affecting the detection sensitivity in molecular SIMS and other desorption techniques as well is believed to be the poor ionization probability of a sputtered molecule, a value which is often assumed to be as low as 10–5 but at present is basically unknown. In order to estimate how much headroom there is for future developments toward strategies aimed at enhancing the ionization probability, we study the protonation efficiency of sputtered guanine molecules for formation of [M + H]+ secondary ions using strong field laser postionization (LPI) to detect the corresponding neutral molecules. In order to allow a quantitative comparison of secondary ion and neutral yields, the postionization signal is corrected for undersampling of the principally detectable plume of sputtered neutral particles by t...

On the SIMS Ionization Probability of Organic Molecules.

The prospect of improved secondary ion yields for secondary ion mass spectrometry (SIMS) experiments drives innovation of new primary ion sources, instrumentation, and post-ionization techniques. The largest factor affecting secondary ion efficiency is believed to be the poor ionization probability (α+) of sputtered material, a value rarely measured directly, but estimated to be in some cases as low as 10-5. Our lab has developed a method for the direct determination of α+ in a SIMS experiment using laser post-ionization (LPI) to detect neutral molecular species in the sputtered plume for an organic compound. Here, we apply this method to coronene (C24H12), a polyaromatic hydrocarbon that exhibits strong molecular signal during gas-phase photoionization. A two-dimensional spatial distribution of sputtered neutral molecules is measured and presented. It is shown that the ionization probability of molecular coronene desorbed from a clean film under bombardment with 40 keV C60 cluster projectiles is of the order of 10-3, with some remaining uncertainty arising from laser-induced fragmentation and possible differences in the emission velocity distributions of neutral and ionized molecules. In general, this work establishes a method to estimate the ionization efficiency of molecular species sputtered during a single bombardment event. Graphical Abstract <!-- [INSERT GRAPHICAL ABSTRACT TEXT HERE] -->.

Calcium Silicate Phases Explained by High-Temperature-Resistant Phosphate Probe Molecules.

In this work, high-temperature-resistant phosphate molecules are applied to characterize ultrathin (100 nm) calcium silicate (C-S) phases. These C-S phases are synthesized on silicon wafers, and the interaction of phosphates with the C-S phases is studied by means of in situ transmission Fourier transform infrared (FTIR) spectroscopy. At room temperature, the chemistry of the system is dominated by the formation of calcium phosphates (C-P). In the case of temperature rising to 1000 °C, the C-S phases are regenerated. FTIR results are analyzed on the basis of first-principles calculations and further supported by complementary time-of-flight secondary ion mass spectrometry (ToF-SIMS) experiments. This study provides a detailed and self-consistent picture of the chemical and structural properties of interfaces such as the one between the atmosphere and ultrathin C-S phases (gas/C-S) and the one between them and silicon wafers (C-S/Si bulk). The material combination of ultrathin C-S phases grown on silicon wafers might in the future have great potential in selective chemistry, catalysis, and sensing technology as well as in semiconductor manufacturing.

Development of a poly(dimethylacrylamide) based matrix material for solid phase high density peptide array synthesis employing a laser based material transfer

Poly(dimethylacrylamide) (PDMA) based matrix materials were developed for laser-based in situ solid phase peptide synthesis to produce high density arrays. In this specific array synthesis approach, amino acid derivatives are embedded into a matrix material, serving as a “solid” solvent material at room temperature. Then, a laser pulse transfers this mixture to the target position on a synthesis slide, where the peptide array is synthesized. Upon heating above the glass transition temperature of the matrix material, it softens, allowing diffusion of the amino acid derivatives to the synthesis surface and serving as a solvent for peptide bond formation. Here, we synthesized PDMA six-arm star polymers, offering the desired matrix material properties, using atom transfer radical polymerization. With the synthesized polymers as matrix material, we structured and synthesized arrays with combinatorial laser transfer. With densities of up to 20,000 peptide spots per cm2, the resolution could be increased compared to the commercially available standard matrix material. Time-of-Flight Secondary Ion Mass Spectrometry experiments revealed the penetration behavior of an amino acid derivative into the prepared acceptor synthesis surface and the effectiveness of the washing protocols.