Post-deposition Thermal Treatment Research Articles

Alternative during‐growth chlorination of sputtered CdTe films and their implementation as activating layers in CdS/CdTe solar cells

AbstractCadmium telluride is an efficient light absorbing material successfully used in solar cell technology. The efficiency of such photovoltaic devices is strongly dependent on post‐deposition thermal treatments in the presence of chlorine. The benefits of this process on the absorbing layer include removal of intragrain defects, grain growth enhancement, and grain boundaries passivation. The absorber chlorination is a crucial step for which CdCl2 is the most common choice. Its use, however, has been overshadowed by the toxicity of Cd‐ and Cl‐containing vapors and residues. In this work, chlorine was incorporated in CdTe films during growth using sputtering targets with different chloride compounds: CdCl2, TeCl4, BaCl2, CaCl2, or LiCl. After characterizing these films, CdTe:CdCl2 and CdTe:TeCl4 were selected as feasible absorbers for testing their performance in photovoltaic devices. Efficiencies near 7% were obtained in as‐grown unoptimized cells in which the absorber consisted of two layers: pristine CdTe and CdTe:CdCl2 or CdTe:TeCl4. The chlorinated layers acted as Cl sources for the adjacent CdTe and CdS, which produced a homogeneous distribution of chlorine throughout the cell. In the during‐growth activating‐layer (DG‐AL) method used here, the chlorine diffusion during growth had a doping effect, passivated grain boundaries and defects, improved the back contact characteristics by reducing the CdTe work function, and lowered the pinhole formation probability by producing a compact chlorinated CdTe layer.

Magnetron Sputtering Deposition of High Quality Cs3Bi2I9 Perovskite Thin Films.

Nontoxic all-inorganic perovskites are among the most promising materials for the realization of optoelectronic devices. Here, we present an innovative way to deposit lead-free, totally inorganic Cs3Bi2I9 perovskite from vapor phase. Taking use of a magnetron sputtering system equipped with a radiofrequency working mode power supply and a single target containing the correct ratio of CsI and BiI3 salts, it was possible to deposit a Cs3Bi2I9 perovskitic film on silicon and soda-lime glass. The target composition was optimized to obtain a stoichiometric deposition, and the best compromise was found with a mix enriched with 20% w/w of CsI. Secondly, the effect of post-deposition thermal treatments (150 °C and 300 °C) and of the deposition on a preheat substrate (150 °C) were evaluated by analyzing the chemical composition, the morphology, the crystal structure, and the optical properties. The thermal treatment at 150 °C improved the uniformity of the perovskite film; the one at 300 °C damaged the perovskite deposited. Depositing on a preheated substrate at 150 °C, the obtained film showed a higher crystallinity. An additional thermal treatment at 150 °C on the film deposed on the preheated substrate showed that the crystallinity remains high, and the morphology becomes more uniform.

Thermal annealing of superconducting niobium titanium nitride thin films deposited by plasma-enhanced atomic layer deposition

Next-generation superconducting radio frequency (SRF) cavities, based on tailored thin films, would allow for more efficient and sustainable accelerators operating at higher accelerating gradients. In particular, superconductor–insulator–superconductor (SIS) multilayers are proposed as a potential alternative to bulk Nb. In this context, NbTiN stands out as a superconducting candidate. Here, we report our studies on NbTiN thin films grown by plasma-enhanced atomic layer deposition (PEALD) in a supercycle approach on AlN in situ deposited on planar silicon substrates. In detail, different ternary compound compositions and thicknesses have been investigated concerning the elemental composition, the superconducting properties, and the crystallinity of the deposited thin films. Two different post-deposition thermal treatments have been applied to Nb0.75Ti0.25N thin films of different thicknesses. Their effect on the film properties has been evaluated. It has been demonstrated that an optimized post-deposition thermal annealing procedure significantly improves the quality of our PEALD deposited Nb0.75Ti0.25N thin films, achieving the highest superconducting critical temperature (Tc) of 15.9 K obtained for films deposited by atomic layer deposition (ALD) so far and a lower critical field (Hc1) of 213 mT, which overpasses the bulk Nb intrinsic limit of 200 mT. Our studies are a promising first stepping stone on the path toward tailored thin films based SRF cavities.

Laser induced crystallization of sputtered MoS2 thin films

The integration of transition metal dichalcogenides (TMDs) thin films into Si CMOS-based devices requires the development of new bottom-up material growth approaches producing high crystallinity films without affecting the SiO2/Si substrate. For this purpose, sputtering is a suitable deposition method due to its simplicity, jointly with high reliability and large area deposition capabilities. However, sputtered layers are amorphous and require a post-deposition thermal treatment to obtain a highly crystalline film. Nanosecond pulsed laser annealing (PLA) has recently emerged as promising route to achieve large-scale crystalline TMDs films without significantly heating or affecting the underlying substrate. The aim of this work is to explore the possibility to produce crystalline 2H–MoS2 on large areas directly on a SiO2-on-Si substrate. The film structure, composition and morphology were monitored as a function of the laser pulse energy density by Raman spectroscopy, X-rays diffraction, Rutherford backscattered spectroscopy (RBS), scanning transmission electron microscopy (STEM) and atomic force microscopy (AFM). The electrical properties of the film with optimized crystallinity were finally investigated through deposition of Cr/Au contacts using shadow masks. This approach can be scaled to other TMDs materials and substrates, also paving the way for the fabrication of heterostructures and electrical devices on the top of a single substrate.

Effects of the processing variables on the optical properties of P3HT:PCBM absorber layer: A statistical point of view

The organic solar cells (OSCs) stand out due to their low cost and possibility to be flexible; however, it is well known that small deviations of the manufacturing variables could affect their performance. Therefore, in this work, we conducted a systematic study of the effects of the precursor solution (PS) processing and the post-deposition thermal treatment (TT) on the optical properties of P3HT:PCBM absorber-layer, by applying a Central Composite Design of Experiments. Results revealed that the temperature is the factor with the greatest influence on material properties; while the stirring time by itself is the least significant; however, its interaction with high temperature promotes the structural disorder, inducing degradation of the absorber layer. The DoE showed that P3HT:PCBM layers with appropriate optical properties to be applied in OSCs are fabricated with a PS stirred at 53.5 °C for 18 h, and post-deposition TT below to 150 °C. These results were corroborated with X-ray diffraction, microscope optical images, and electrical and optical responses of manufactured solar cells.

Stability of Cu2ZnSnSe4/CdS heterojunction based solar cells under soft post-deposition thermal treatments

The thermal stability of the Cu 2 ZnSnSe 4 (CZTSe) absorber and CdS buffer layers in SLG/Mo/CZTSe/CdS/i-ZnO/ITO devices is explored by performing a series of soft (∼200 °C) post deposition treatments (PDTs). A comprehensive analysis of a sample comprised by 56 individual devices by means of Raman and photoluminescence spectroscopies coupled with optoelectronic characterization is performed at different PDT steps. This allows isolating the effects of the PDT on the CZTSe absorber and CdS buffer layer separately and reveals clear evidences of: i) a degradation of the absorber due to Cu/Zn disorder that hinders device performance, and ii) an improvement of the buffer layer by the recrystallization of the CdS nanolayer that is the main responsible for the PDT-induced efficiency improvement. As such, it is concluded that CZTSe/CdS based PV devices present a low thermal stability under relatively low temperatures (in the 100–200 °C range), comparable to the temperatures employed at the final production stages of thin film PV devices or even during device operation, that leads to significant changes in solar cell performance and needs to be taken into consideration for the further development of the kesterite PV technology. These results are supported by a novel methodology for easily discerning between changes in Cu/Zn disorder and in point defects concentration in kesterites based on solely on Raman spectroscopy that is proposed in this work and developed through the analysis of a set of CZTSe powder samples with strong variation of the order parameter Q. • The CZTSe/CdS heterojunction is unstable under soft post deposition treatment (PDT). • Soft PDT induced performance improvement arises from a recrystallization of the CdS. • Soft PDT induces detrimental Cu/Zn disorder at the CZTSSe absorber layer. • Raman spectroscopy can discern between changes in disorder and defect concentration.

Spongy TiO2 layers deposited by gig-lox sputtering processes: Contact angle measurements

The use of nanostructured materials is increasingly widespread thanks to their particular properties that can improve the performance of devices in various scientific applications. One of them is in the architecture of perovskite solar cells characterized by high photoconversion efficiency values that make them able to compete with silicon solar cells. In this framework, we deposited TiO2 sponges by reactive sputtering based on a grazing-incidence geometry combined with the local oxidation of species. The deposited material gains 50% porosity in volume through depths of hundreds of nanometers and consists of a forest of uniform rods separated by mesopores (pipelines) arising from the grazing geometry. Many previous studies showed how TiO2 can improve the efficiency of perovskite solar cells. In this article, we investigated the change of the wettability values of the TiO2 samples before and after a postdeposition thermal annealing treatment. For comparison, the influence of the annealing on the wettability of the glass substrate is also reported.

Influence of Post-Deposition Thermal Treatments on the Morpho-Structural, and Bonding Strength Characteristics of Lithium-Doped Biological-Derived Hydroxyapatite Coatings

We report on hydroxyapatite (HA) of biological-origin doped with lithium carbonate (LiC) and lithium phosphate (LiP) coatings synthesized by Pulsed laser deposition onto Ti6Al4V substrates fabricated by the Additive manufacturing technique. A detailed comparison from the structural, morphological, chemical composition, wetting behavior and bonding strength standpoints of as-deposited (NTT) and post-deposition thermal-treated (TT) coatings at temperatures ranging from 400 to 700 °C (i.e., TT400–TT700), was performed. Structural investigations indicated a complete crystallization of the initially amorphous HA-based layers at temperatures in excess of 500 °C. The morphological analyses emphasized the rough appearance of the film surfaces, consisting of particulates whose dimensions increased at higher temperatures, with an emphasis on LiC coatings. AFM investigations evidenced rough surfaces, with a clear tendency to increase in corrugation with the applied temperature, in the case of LiC coatings. A hydrophobic behavior was observed for control, NTT and TT400 samples, whilst a radical shift towards hydrophilicity was demonstrated for both types of structures at higher temperatures. In the case of TT500–TT700 coatings, the pull-out adherence values increased considerably compared to control ones. Taking into consideration the obtained results, the positive influence of post-deposition thermal treatments (performed at higher temperatures) on the physical–chemical and mechanical properties of LiC and LiP coatings was indicated. Alongside these improved characteristics observed at elevated temperatures, the sustainable nature of the used BioHA materials should recommend them as viable alternatives to synthetic HA ones for bone implant applications.

Effect of Post-Deposition Thermal Treatments on Tensile Properties of Cold Sprayed Ti6Al4V

This study aims at investigating the effect of various post-deposition thermal treatments on improving tensile properties of cold spray (CS) deposited titanium alloy Ti6Al4V. Dogbone-shaped tensile specimens were designed considering two application scenarios: ‘fully CS’ specimens, and ‘CS repair’ specimens. For both specimen types, tests were carried out in four conditions: (i) as-deposited (AD), and after three different thermal treatments, i.e., (ii) solution treatment and ageing (STA), (iii) hot isostatic pressing (HIP), and (iv) HIP followed by STA (HIP + STA). Complementary to tensile testing, characterisation of CS deposited material was also carried out in terms of microstructure and hardness. The STA process resulted in the highest improvement in ultimate tensile strength by more than 200%, reaching 868 MPa for ‘fully CS’ and 951 MPa for ‘CS repair’ specimens. However, no appreciable improvement in elongation at failure was achieved, highest being 1.2% for ‘fully CS’ after STA, and 4.3% for ‘CS repair’ after HIP. In addition to experimental investigation, a comprehensive collection of data from the open literature on the effect of various thermal treatments on improving the tensile properties of CS Ti6Al4V deposits is reported and discussed.

Effect of thermal treatment and deposition conditions of ZnO by radio frequency sputtering on the photovoltaic response of CdTe solar cells

ZnO thin films grown by radio frequency sputtering were studied as a function of the experimental parameters: source power, chamber deposition pressure, substrate temperature and oxygen partial pressure; in addition to post-deposition thermal treatment. The ZnO thin films were characterized by stylus profilometry, optical measurements, electrical resistivity, X-ray diffraction, energy dispersive spectroscopy and scanning electron microscopy. Current-voltage and external quantum efficiency measurements were performed on the CdS/CdTe-based solar cell. In the case of ZnO/CdS thin films with a high-temperature thermal treatment, an increment in transmittance was observed in the ZnO wavelength region. With the incorporation of the ZnO thin film in the front contact of the solar cell, we obtained a photovoltaic efficiency of 7.4%, with the following optimal deposition conditions: 230 W source power, 2.67 Pa of deposition pressure and 300°C for the substrate temperature with a thermal treated of 450 °C for ZnO/CdS thin films. While a photovoltaic efficiency of 6.0% was obtained, when the ZnO/CdS was thermal treated at 500°C with the ZnO deposited at 140 W source power, 1.33 Pa deposition pressure and 250 °C for the substrate temperature. Finally, a photovoltaic efficiency of 10% was achieved for CdTe solar cells with ZnO thin film by combining the experimental conditions and the thermal treatment described above.

Pulsed-laser deposition and photocatalytic activity of pure rutile and anatase TiO2 films: Impact of single-phased target and deposition conditions

Titanium dioxide is a technologically interesting material in many applicative fields that, however, exhibits critical aspects in terms of phase purity and synthesis/growth conditions.The presented work deals with the deposition, in vacuum, of single-phase rutile and anatase titania films by excimer laser ablation (λ = 248 nm) of anatase and rutile targets. Post-deposition thermal treatment at 450 °C in air was applied to drive the crystalline evolution of the as-deposited films, limit oxygen desorption and avoid changes in the polymorph phase.Unlike the typical use of oxygen as a background gas and Ti target in pulsed laser deposition of TiO2, our setting vacuum background atmosphere not only allows to relate the final phase of the film directly to the target phase but also to rule out phase transitions and mixed-phase, by the interplay between post-growth temperature and limited oxygen desorption. Herein, we study and discuss how the ablation process impacts on and determines film composition and morphology. The discussed influence of the target phase on the optical, morphological and photocatalysis properties of the titania films points out good performances of our samples and the importance to tune deposition to obtain the titania polymorph phase more suitable for specific applications.

Optimizing Oxygen Plasma Treatment Time to Improve the Characteristics of a-IGZO Thin-Film Transistors and Resistive-Load Inverters

Amorphous indium–gallium–zinc oxide (a-IGZO) is a widely studied semiconductor for cutting-edge electronics applications because of its low absorbance, high charge carrier mobility, and versatility. For the practical application of a-IGZO thin films, postdeposition thermal treatment is typically applied to enhance the device’s performance. Here, we present a study on the effect of oxygen plasma posttreatment of thermally annealed, sputter-deposited a-IGZO thin films to determine the optimal treatment time using a helical plasma source. The performance of devices with a-IGZO active layers exposed to oxygen plasma for different durations is compared, and the stability under constant bias is evaluated. It is found that temporarily exposing the film surface to high-energy oxygen species can improve the charge transport properties, resulting in superior device performance such as more than tenfold increase in the ON–OFF ratio, a nearly doubling of charge carrier mobility and improved bias stress stability. However, under prolonged exposure, the device deteriorates, indicating the importance of properly designing and optimizing the fabrication processes of oxide semiconductor devices. To demonstrate the practical applicability of the transistors with optimized a-IGZO active layers, load-type inverters are prepared, and their performance is evaluated and compared quantitatively to that of a device with a pristine a-IGZO active layer.

Defect- and H-Free Stoichiometric Silicon Carbide by Thermal CVD from the Single Source Precursor Trisilacyclohexane

Stoichiometric silicon carbide (SiC) thin films were grown using thermal chemical vapor deposition (TCVD) from the single source precursor 1,3,5-trisilacyclohexane (TSCH) on c-Si (100) substrates within an optimized substrate temperature window ranging from 650 to 850 °C. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analyses revealed that the as-deposited films consisted of a Si-C matrix with a Si:C ratio of ~1:1. FTIR and photoluminescence (PL) spectrometry studies showed that films deposited ≥ 750 °C were defect- and H-free within the detection limit of the techniques used, while ellipsometry measurements yielded an as-grown SiC average refractive index of ~2.7, consistent with the reference value for the 3C-SiC phase. The exceptional quality of the films appears sufficient to overcome limitations associated with structural defects ranging from failure in high voltage, high temperature electronics to 2-D film growth. TSCH, a liquid at room temperature with good structural stability during transport and handling as well as high vapor pressure (~10 torr at 25 °C), provides a viable single source precursor for the growth of stoichiometric SiC without the need for post-deposition thermal treatment.

Non-stoichiometric gallium oxide with cubic structure directly integrated to C-Cut sapphire

We used oxygen-reactive electron beam evaporation and post-deposition thermal treatment to prepare thin films of gamma-phase gallium oxide (γ-Ga2O3) grown on c-cut sapphire substrates. Films were prepared at room temperature under different partial pressures of oxygen present (from 1.0 mPa to 8.0 mPa). After thermal treatments at 600.0 °C for 30 min, the films have different surface morphologies, which is evidences by atomic force microscopy. Scanning electron microscopy with energy dispersive spectroscopy analyses reveal the formation of non-stoichiometric Ga2O3 films, that uniform coat the substrates. X-ray diffraction analyses reveal the formation of γ-Ga2O3-x (0.4 < x < 0.6) with crystalline planes (001) preferably oriented parallel to the substrate surface but slightly tilted (less than ± 0.2°) in relation to the direction [001] of the c-cut sapphire substrates. Raman spectroscopy suggest that films despite structurally oriented present high degree of chemical disorder but with no evidence of other Ga2O3 polytypes formation. Such a simple route for the preparation of non-stoichiometric γ-Ga2O3 is promising for several catalytic applications and developments of light emitting devices.

Flexible Polymer-Organic Solar Cells Based on P3HT:PCBM Bulk Heterojunction Active Layer Constructed under Environmental Conditions.

In this study, some crucial parameters were determined of flexible polymer–organic solar cells prepared from an active layer blend of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) mixed in 1:1 mass ratio and deposited from chlorobenzene solution by spin-coating on poly(ethylene terephthalate) (PET)/ITO substrates. Additionally, the positive effect of an electron transport layer (ETL) prepared from zinc oxide nanoparticles (ZnO np) on flexible photovoltaic elements’ performance and stability was investigated. Test devices with above normal architecture and silver back electrodes deposed by magnetron sputtering were constructed under environmental conditions. They were characterized by current-voltage (I–V) measurements, quantum efficiency, impedance spectroscopy, surface morphology, and time–degradation experiments. The control over morphology of active layer thin film was achieved by post-deposition thermal treatment at temperatures of 110–120 °C, which led to optimization of device morphology and electrical parameters. The impedance spectroscopy results of flexible photovoltaic elements were fitted using two R||CPE circuits in series. Polymer–organic solar cells prepared on plastic substrates showed comparable current–voltage characteristics and structural properties but need further device stability improvement according to traditionally constructed cells on glass substrates.

Effect of the Post-Deposition Thermal Treatment on the Mechanical Properties of a Compositionally Modulated CrAlSiN-AlSiN Coating

A CrAlSiN-AlSiN coating with periodically modulated composition was investigated regarding dependence of the mechanical properties and toughness, morphology, composition, and structure on thermal treatment in the interval of 600–900 °C in argon ambience. The coating exhibited superhardness and high toughness up to 800 °C. A very slight decrease in the nanohardness, resistance to elastic strain to failure, and plastic deformation were observed. The coating had enhanced elastic recovery stable up to 700 °C. It was found that the coating morphology was not substantially influenced by the thermal treatment. X-ray diffraction (XRD) analysis revealed that the modulated coating had a nanocomposite structure, which did not change after annealing, even at 900 °C. The grains were composed mainly of fcc-CrN and h-AlN phases embedded into an amorphous Si3N4 matrix. A small amount of an h-Cr2N phase appeared after heating at temperatures above 700 °C. The coating composition was examined by energy-dispersive X-ray spectroscopy (EDS). The coating was stoichiometric up to 800 °C. It became sub-stoichiometric with respect to nitrogen after annealing at 800 °C and 900 °C. It is thus concluded that the CrAlSiN-AlSiN coating with a periodically modulated structure keeps the combination of superhardness (45.3 GPa) and improved toughness (H3/E*2 = 0.362 GPa, elastic recovery 57%) at temperatures up to 800 °C, and is suitable for high thermal applications.

Influence of the Sputtering Technique and Thermal Annealing on YSZ Thin Films for Oxygen Sensing Applications

Yttria-stabilized zirconia (YSZ) thin films were deposited using direct current (reactive and metallic) and radio frequency magnetron sputtering. The effect of the deposition technique and annealing treatment on the microstructure and crystallinity of the thin films was assessed. Using the films produced in this work, oxygen gas sensors were built and their performance under vacuum conditions was evaluated. All the films exhibited a cubic crystalline structure after a post-deposition thermal treatment, regardless of the sputtering technique. When the annealing treatment surpassed 1000 °C, impurities were detected on the thin film surface. The oxygen gas sensors employing the reactive and oxide-sputtered YSZ thin films displayed a proportional increase in the sensor current as the oxygen partial pressure was increased in the evaluated pressure range (5 × 10−6 to 2 × 10−3 mbar). The sensors which employed the metallic-deposited YSZ films suffered from electronic conductivity at low partial pressures.

Physical properties of photoconductive Ag-Sb-S thin films prepared by thermal evaporation

We used thermal evaporation and post-deposition thermal treatment to prepare photoconductive Ag-Sb-S thin films. Firstly, to obtain the Ag2S/Sb2S3/substrate samples, we sequentially evaporated both Sb2S3 and Ag2S precursors. Secondly, we converted the double-layered structure in Ag-Sb-S thin films through a post-annealing treatment. Finally, considering the variation in both temperature of this treatment and amount of evaporated Ag2S, we evaluated the formation of AgSbS2 and Ag3SbS3 ternary phases in the films. As a result, we identified the coexistence of cubic and monoclinic AgSbS2 and monoclinic and hexagonal Ag3SbS3 phases. In addition, the evolution from metastable to stable phases of AgSbS2 and Ag3SbS3 is presented.Using Raman vibrational modes at 267 cm-1 for the monoclinic and 323 cm-1 for the hexagonal phases and X-ray diffraction results, we identified the dominant Ag3SbS3 crystalline structure. Furthermore, we found that, respectively, the optical band gap, electrical conductivity and photosensitivity are in the range of 1.7–1.85 eV, 1.3 × 10-7 to 7.4 × 10-5 (Ω-cm)-1 and 29 to 0.5. Consequently, the Ag-Sb-S thin films are suitable as the absorber layer in photovoltaic solar cells.

Kesterite Solar Cells: Insights into Current Strategies and Challenges.

Earth‐abundant and environmentally benign kesterite Cu2ZnSn(S,Se)4 (CZTSSe) is a promising alternative to its cousin chalcopyrite Cu(In,Ga)(S,Se)2 (CIGS) for photovoltaic applications. However, the power conversion efficiency of CZTSSe solar cells has been stagnant at 12.6% for years, still far lower than that of CIGS (23.35%). In this report, insights into the latest cutting‐edge strategies for further advance in the performance of kesterite solar cells is provided, particularly focusing on the postdeposition thermal treatment (for bare absorber, heterojunction, and completed device), alkali doping, and bandgap grading by engineering graded cation and/or anion alloying. These strategies, which have led to the step‐change improvements in the power conversion efficiency of the counterpart CIGS solar cells, are also the most promising ones to achieve further efficiency breakthroughs for kesterite solar cells. Herein, the recent advances in kesterite solar cells along these pathways are reviewed, and more importantly, a comprehensive understanding of the underlying mechanisms is provided, and promising directions for the ongoing development of kesterite solar cells are proposed.

Role of Postdeposition Thermal Annealing on Intracrystallite and Intercrystallite Structuring and Charge Transport in Poly(3-hexylthiophene)

The performance of electronic devices comprising conjugated polymers as the active layer depends not only on the intrinsic characteristics of the materials but also on the details of the extrinsic processing conditions. In this study, we examine the effect of postdeposition thermal treatments on the microstructure of poly(3-hexylthiophene) (P3HT) thin films and its impact on their electrical properties. Unsurprisingly, we find thermal annealing of P3HT thin films to generally increase their crystallinity and crystallite coherence length while retaining the same crystal structure. Despite such favorable structural improvements of the polymer active layers, however, thermal annealing at high temperatures can lead to a net reduction in the mobility of transistors, implicating structural changes in the intercrystallite amorphous regions of these semicrystalline active layers take place on annealing, and the simplistic picture that crystallinity governs charge transport is not always valid. Our results instead suggest tie-chain pullout, which occurs during crystal growth and perfection upon thermal annealing to govern charge transport, particularly in low-molecular-weight systems in which the tie-chain fraction is low. By demonstrating the interplay between intracrystallite and intercrystallite structuring in determining the macroscopic charge transport, we shed light on how structural evolution and charge-transport properties of nominally the same polymer can vary depending on the details of processing.