| 1. Domain | 1.1 Scope of the Domain | Boundaries | The range of phenomena the science includes and excludes. | Includes electronic and optical behavior of materials with engineered band gaps, charge transport in doped materials, excitonic effects, recombination processes, junction behavior, and carrier dynamics. Excludes metals with fully filled or empty bands, insulators with extremely large gaps, and systems lacking controllable carrier populations. |
| | Scale | The spatial, temporal, or organizational level at which the science operates (e.g., quantum, cellular, social, cosmic). | Operates from atomic and nanometer scales (band structure, dopants, excitons) to micrometer and millimeter device scales (junctions, transistors). Time scales range from ultrafast optical transitions to slower thermal or recombination processes. |
| 1.2 Ontological Commitments | Entities | The kinds of things assumed to exist within the domain (particles, organisms, agents, fields, etc.). | Electrons, holes, dopant atoms, excitons, charge traps, phonons, electric fields, energy bands, and quasiparticles that represent effective carrier behavior in the solid. |
| | Properties | The fundamental attributes these entities possess (mass, charge, genotype, preference, etc.). | Charge, mobility, effective mass, carrier lifetime, band gap energy, recombination rate, dielectric constant, and optical absorption characteristics. |
| | Categories | The basic ontological types used to classify domain elements (substances, processes, relations, structures). | Materials, carriers, junctions, optical transitions, scattering processes, band structures, and device-relevant structures such as depletion regions and potential barriers. |
| 1.3 State-Variables | Variables | The measurable or definable properties that describe system conditions. | Carrier density, band energies, Fermi level position, electric potential, recombination rate, mobility, temperature, and impurity concentration. |
| | Parameterization | How variables encode and represent the system’s state. | System states encoded by band diagrams, doping profiles, carrier statistics, potential distributions, temperature settings, and externally applied fields. |
| 1.4 Admissible Idealizations | Simplifications | Conceptual reductions used to make the domain tractable (point masses, rational agents, perfect gases). | Idealizations include treating carriers as independent, assuming perfect crystal structure, neglecting many-body interactions, applying simple band models, and using uniform doping approximations. |
| | Validity Conditions | The limits and contexts in which idealizations hold or break down. | Idealizations hold when defect density is low, doping is uniform, carrier interactions are weak, and temperature ranges allow stable band behavior without strong nonlinear effects. |
| 1.5 Domain Assumptions | Structural Assumptions | Background ontological stances such as determinism, continuity, randomness, discreteness. | Assumes semiconductor bands exist and are stable, charge carriers follow statistical rules, material structure is continuous at the scale of interest, and doping controls carrier populations predictably. |
| | Implicit Commitments | Unstated but necessary assumptions that shape the field’s conceptual structure. | Assumes band theory effectively captures electron behavior, dopant effects can be treated as modifying carrier density rather than altering structure, and device-scale models faithfully represent underlying microscopic physics. |
| 1.6 Internal Coherence Requirements | Consistency | The demand that domain concepts do not contradict one another. | Requires agreement between band structure, carrier dynamics, doping effects, optical transitions, and transport models; parameters must not contradict measured material properties. |
| | Compatibility | The requirement that entities, variables, and assumptions fit together into a unified descriptive framework. | Variables, entities, and assumptions must produce a unified description linking band gaps, doping behavior, carrier motion, recombination, and device operation without internal conflict. |
| 2. Evidence Layer | 2.1 Observable Phenomena | Observables | The aspects of the domain that can produce detectable signals accessible to measurement. | Detectable signals include current flow, voltage response, photoluminescence, absorption spectra, carrier lifetime signatures, mobility measurements, junction characteristics, and temperature-dependent transport behavior. |
| | Detection Limits | The boundaries of what can be resolved or sensed by current instruments or methods. | Limited by the sensitivity of electrical probes, optical detectors, noise floors, spatial resolution of microscopes, the ability to resolve small carrier concentrations, and the precision of temperature or field control. |
| 2.2 Measurement Systems | Units | Standardized quantifications (meters, seconds, volts, decibels, dollars, etc.) necessary for consistent comparison. | Common units include volts, amperes, ohms, meters, seconds, electron volts, kelvins, carrier density per cubic centimeter, and mobility in square centimeters per volt-second. |
| | Instruments | Devices and tools (microscopes, spectrometers, sensors, surveys, detectors) used to produce measurements. | Instruments include semiconductor parameter analyzers, oscilloscopes, photodetectors, spectrometers, Hall effect setups, electron microscopes, scanning probe tools, and cryostats for temperature control. |
| 2.3 Operational Definitions | Definitions | Terms defined by specific measurement procedures, ensuring empirical clarity. | Quantities such as band gap, carrier mobility, carrier lifetime, doping concentration, threshold voltage, and quantum efficiency are defined by precise measurement procedures. |
| | Procedures | The explicit steps required to perform a measurement in a reproducible way. | Procedures include current-voltage sweeps, capacitance-voltage profiling, optical absorption scans, Hall effect measurements, photoluminescence collection, and time-resolved carrier decay experiments. |
| 2.4 Data Acquisition | Protocols | Formal processes for gathering data under controlled or standardized conditions. | Data collected under controlled temperature, stable illumination, calibrated field application, fixed contact geometry, and standardized timing or sampling rates. |
| | Sampling | Rules determining which subset of the domain is measured and how representative it is. | Sampling rules specify measurement at multiple doping levels, several temperatures, repeated spatial locations, or at various applied voltages to ensure representative data. |
| 2.5 Data Character & Format | Data Types | The form raw evidence takes (time series, spectra, images, counts, qualitative records). | Data appears as IV curves, CV curves, spectra, decay traces, microscopic images, carrier density tables, and temperature-dependent transport plots. |
| | Resolution | The granularity or precision with which data is captured. | Determined by detector sensitivity, sampling rate, voltage precision, optical bandwidth, temperature stability, and measurement noise. |
| 2.6 Reliability & Calibration | Calibration | Adjustment procedures ensuring instruments produce accurate results. | Calibration uses reference semiconductor materials, known doping standards, calibrated light sources, temperature benchmarks, and repeated zero-offset checks on instruments. |
| | Error Characterization | Identification and quantification of noise, uncertainty, bias, and measurement error. | Errors arise from contact resistance, thermal drift, probe misalignment, detector noise, sample contamination, finite sampling, and calibration uncertainty. |
| 3. Structural Layer | 3.1 Patterns & Regularities | Laws / Relations | Stable, repeatable patterns governing how observables behave across conditions. | Stable relations include the dependence of conductivity on carrier density and mobility, the relationship between band gap and optical absorption, predictable junction behavior, and thermal activation patterns in carrier populations. |
| | Invariants | Quantities or properties that remain constant under transformations (symmetries, conservation laws). | Invariants include band symmetry, selection rules for optical transitions, conserved charge in transport, and stable structural features based on crystal type or doping pattern. |
| 3.2 Causal Architecture | Mechanisms | Underlying processes or structures that produce the observed regularities. | Mechanisms arise from interactions between electrons and lattice atoms, dopant-induced carrier modification, phonon scattering, impurity scattering, recombination processes, and exciton formation. |
| | Pathways | Organized sequences of interactions forming a causal chain or network. | Pathways include carrier excitation from valence to conduction band, relaxation through scattering, recombination via radiative or nonradiative channels, and diffusion or drift under external fields. |
| 3.3 Theoretical Vocabulary | Concepts | Core terms that encode the domain’s structure (force, gene, equilibrium, field). | Core concepts include band gap, carrier mobility, effective mass, Fermi level, doping, recombination, exciton, junction, depletion region, and charge neutrality. |
| | Classifications | Taxonomies, categories, or typologies that organize entities and relations. | Classifies materials as intrinsic, n-type, p-type, direct-gap, indirect-gap, degenerate, wide-gap, narrow-gap, crystalline, or amorphous depending on band structure and doping level. |
| 3.4 Formal Representations | Equations | Mathematical constructs expressing laws, relations, or mechanisms. | Uses equations for carrier statistics, current flow, recombination rates, energy bands, drift-diffusion dynamics, and optical absorption. |
| | Models | Structured representations—mathematical, computational, or conceptual—used to predict and explain phenomena. | Includes band structure models, drift-diffusion models, recombination models, carrier statistics models, junction models, and computational simulations of semiconductor behavior. |
| 3.5 Idealized Structures | Simplified Models | Purposeful abstractions that capture essential dynamics while omitting irrelevant detail. | Idealizations include perfect-crystal models, effective mass approximation, simple parabolic band models, uniform doping assumptions, and harmonic approximations of lattice vibrations. |
| | Limit Conditions | Regimes where specific models or approximations hold (classical vs. quantum, linear vs. nonlinear). | Approximations hold when defect concentration is low, carrier interactions are weak, temperature is in suitable range, and material structure is stable enough to support simplified band or transport models. |
| 3.6 Integrative Frameworks | Unifying Theories | Higher-order structures that connect disparate laws or mechanisms under a coherent whole. | Unifying frameworks include band theory, drift-diffusion equations, semiconductor device equations, and effective quasiparticle models linking microscopic physics to device-scale behavior. |
| | Interdisciplinary Links | Points where the theory connects to adjacent sciences or larger explanatory systems. | Links to materials science, electrical engineering, nanotechnology, surface physics, optoelectronics, and computational modeling of electronic materials. |
| 4. Method Layer | 4.1 Inquiry Design | Experimental Design | Structured plans for manipulating variables to test causal claims. | Experiments manipulate temperature, electric field, magnetic field, illumination, doping concentration, or sample geometry to test causal effects on transport, recombination, optical absorption, and device performance. |
| | Observational Design | Systematic approaches for gathering non-manipulated data (surveys, field studies, natural experiments). | Observational approaches measure natural device behavior, ambient defect migration, thermal drift, or spontaneous recombination without directly controlling variables. |
| 4.2 Testing & Validation | Hypothesis Testing | Procedures for evaluating whether evidence supports or contradicts specific claims. | Tests compare measured IV curves, CV data, spectra, recombination dynamics, or carrier density responses to predictions from semiconductor models such as drift-diffusion or band theory. |
| | Replication | The requirement that results be independently reproducible under similar conditions. | Replication requires confirming results across different samples, fabrication batches, measurement setups, and laboratories to rule out device-specific or sample-specific effects. |
| 4.3 Inference & Evaluation | Statistical Inference | Rules for drawing conclusions from noisy or incomplete data. | Statistical tools analyze noise in transport data, extract carrier densities and mobilities, fit recombination curves, determine doping from capacitance data, and quantify uncertainty. |
| | Model Comparison | Criteria (fit, simplicity, predictive accuracy, robustness) used to evaluate competing models. | Compares models based on accuracy of predicted band gaps, transport behavior, recombination trends, temperature dependence, and ability to reproduce device-level measurements. |
| 4.4 Error Management | Error Analysis | Identification and quantification of random and systematic errors. | Errors arise from contact resistance, thermal noise, calibration drift, misalignment, photodetector noise, surface contamination, and nonuniformity in doping or sample thickness. |
| | Bias Control | Methods for minimizing subjective, instrumental, or procedural biases. | Bias minimized through standardized fabrication, blind measurement sequences, repeated calibrations, independent verification using multiple instruments, and consistent environmental control. |
| 4.5 Adjudication & Revision | Peer Scrutiny | Collective evaluation of claims through critique, review, and debate. | Results undergo review in device engineering meetings, research seminars, peer-reviewed publications, and cross-checking through simulations and independent experimental groups. |
| | Theory Revision | Procedures for modifying, replacing, or discarding models based on new evidence. | Theories updated when discrepancies arise between model predictions and measurements, requiring revised band diagrams, updated recombination models, or improved transport equations. |
| 4.6 Integrity Conditions | Transparency | Requirements to disclose methods, data, assumptions, and limitations. | Requires full disclosure of sample preparation methods, doping levels, measurement configurations, calibration steps, assumptions in modeling, and known limitations. |
| | Ethical Standards | Norms ensuring responsible conduct in experimentation, data handling, and publication. | Requires accurate reporting of measurements, responsible fabrication practices, correct representation of model limitations, and avoidance of selective or misleading data use. |