Skip to content

Rapid Thermal Processing (RTP)

Rapid Thermal Processing provides fast heating and cooling for annealing, oxidation, nitridation, and other thermal treatments. RTP is essential for activating dopants, improving crystallinity, and modifying material properties without extended high-temperature exposure.

Overview

This schema package defines:

  • DtuRTP - A rapid thermal processing step with temperature profiles, atmosphere control, and timing

The RTP process extends NOMAD's Process and Activity base classes, providing:

  • Links to input samples/libraries and output (modified) samples
  • Temperature profiles (ramp rates, hold times, cooling rates)
  • Atmosphere control (gas composition, pressure)
  • Multi-step thermal cycles
  • Automated workflow integration

Typical Usage

  1. Select samples: Reference samples or libraries to be processed
  2. Define thermal profile: Set ramp-up rate, peak temperature, hold time, cooling rate
  3. Set atmosphere: Choose gas environment (Ar, O₂, N₂, forming gas, vacuum)
  4. Document equipment: Reference the RTP instrument used
  5. Link output: Updated sample properties (crystallinity, oxidation state, etc.)

Key Parameters

  • Temperature profile: Ramp rate, peak temperature, hold time, cooling rate
  • Atmosphere: Gas type, flow rate, pressure
  • Sample positioning: Multiple samples, temperature uniformity considerations
  • Cycle steps: Multi-step profiles for complex treatments

Common RTP Applications

  • Crystallization: Improving as-deposited amorphous or poorly crystalline films
  • Annealing: Stress relief, grain growth, defect reduction
  • Oxidation/Nitridation: Forming oxide or nitride layers
  • Dopant activation: Activating implanted or incorporated dopants
  • Interface engineering: Promoting reactions at interfaces

Why Document RTP Details?

Thermal history critically affects material properties:

  • Temperature affects: Phase transitions, grain size, crystallinity
  • Ramp/cooling rates affect: Stress, defect density, phase stability
  • Atmosphere affects: Oxidation state, composition, surface chemistry
  • Time affects: Diffusion, grain growth, decomposition

Detailed records enable:

  • Optimizing thermal treatments
  • Understanding structure-property relationships
  • Reproducing successful conditions
  • Avoiding destructive over-processing

Parsing Workflow

The RTP parser automatically processes thermal treatment log files and extracts relevant process information through a multi-step workflow:

Data Logging

The logging of RTP-related signals includes thermal properties, process gases, and pressure data collection. This is achieved by combining the native software of the RTP tool (CX-Thermo) and the sputtering tool (Lesker Eklipse). Relevant logged quantities include:

  • Gas flow rates
  • Chamber pressure
  • Chamber temperature
  • Power applied to the lamps

Process Step Identification

The data is uploaded to the RTP entry in the form of two distinct log files and automatically processed using the developed parser. Similar to the sputtering data parser, the logic consists of unambiguously identifying the different steps of the annealing process.

The steps belong to one of three categories:

  • Heating: Initial setpoint temperature is lower than final setpoint temperature
  • Annealing plateau: Initial and final setpoint temperatures are identical
  • Cooling: Initial setpoint temperature is higher than final setpoint temperature

These setpoints are timestamped, along with all other signals from both log files, making correlation possible. The timestamped setpoint temperature serves as the basis for the parser logic.

This approach remains valid even when experimentalists use multiple steps of one type (e.g., two heating steps with different ramps, or two heating steps separated by an intermediate annealing plateau), showcasing the high degree of adaptability to real laboratory workflows.

Parameter Extraction

From an experimental perspective, useful information not obtained directly from the log files is automatically extracted, including:

  • Partial pressure of each gas present in the RTP chamber during annealing
  • Heating and cooling rates
  • Other derived parameters calculated from identified process events

Schema Population

Derived parameters are mapped to their corresponding fields in the RTP schema, similar to the sputtering workflow. This enables users to access process details organized:

  • By individual step
  • As an overview of the entire process

Visualization

Similar to the sputtering workflow, the annealing process benefits from automatic plot generation, enabling quick visualization of key aspects:

  • Temperature profiles and setpoints as a function of time
  • Atmosphere composition during annealing
  • Pressure stability during annealing

This organized access to critical parameters makes it easier to identify trends or anomalies that might otherwise go unnoticed, reinforcing the FAIR-by-design principle.

Input Sample Handling

A key difference between sputtering and RTP processes:

  • Sputtering: Uses bare substrates as input
  • RTP: Uses previously deposited combinatorial libraries as input

Input samples can be:

  • Whole combinatorial libraries from the sputtering process
  • Child libraries created by cleaving a parent library

The user provides information about which input samples were introduced in the RTP chamber. By processing this information, output combinatorial libraries are automatically created and named according to established conventions.

Example: If four child combinatorial libraries are mounted horizontally on the sample holder, four independent output combinatorial libraries are created following the naming convention (by user, by iteration number, and position on holder) and referencing:

  • The RTP process that generated them
  • The corresponding parent combinatorial libraries each was cleaved from

Schema Documentation

DtuRTPInputSampleMounting

description: Section containing information about the mounting of the combinatiorial libraries (input samples) on the susceptor.

inherits from: nomad.datamodel.data.ArchiveSection

properties:

name type
name str The name of the input sample mounting.
input_combi_lib nomad_dtu_nanolab_plugin.schema_packages.sample.DTUCombinatorialLibrary The input sample (combinatorial library) that is used.
relative_position str The relative position of the input sample on the susceptor.
position_x float64 The x-coordinate of the input sample on the susceptor.
unit=meter
position_y float64 The y-coordinate of the input sample on the susceptor.
unit=meter
rotation float64 The angle between the initial position in the "mother" sample and the position on the susceptor.
unit=radian

normalization:

The normalizer for the DtuRTPInputSampleMounting class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.

RTPOverview

description: Section containing a human readable overview of the RTP process.

inherits from: nomad.datamodel.data.ArchiveSection

properties:

name type
material_space str The material space explored by the RTP process.
annealing_pressure float64 Pressure in the RTP chamber during the annealing plateau
unit=pascal
annealing_time float64 Time spent at the annealing plateau of the RTP process.
unit=second
annealing_temperature float64 Temperature during the annealing plateau of the RTP process.
unit=kelvin
annealing_ar_flow float64 Argon flow used during the annealing plateau of the RTP process.The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
annealing_n2_flow float64 Nitrogen flow used during the annealing plateau of the RTP process. The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
annealing_ph3_in_ar_flow float64 Phosphine flow used during the annealing plateau of the RTP process. The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
annealing_h2s_in_ar_flow float64 H2S flow used during the annealing plateau of the RTP process.The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
total_heating_time float64 Total time spent until maximum (main annealing plateau)temperature is reached.
unit=second
total_cooling_time float64 Total time spent between the end of the main annealing plateau until the samples are cooled down to room temperature.
unit=second
end_of_process_temperature float64 Temperature at the cooling state of the RTP process, when the gases are shut off and final pump-purge procedure is initiated to remove samples from chamber.
unit=kelvin
annealing_ph3_partial_pressure float64 Partial pressure of PH3 during the annealing plateau of the RTP process.
unit=pascal
annealing_h2s_partial_pressure float64 Partial pressure of H2S during the annealing plateau of the RTP process.
unit=pascal
annealing_n2_partial_pressure float64 Partial pressure of N2 during the annealing plateau of the RTP process.
unit=pascal
annealing_ar_partial_pressure float64 Partial pressure of Ar during the annealing plateau of the RTP process.
unit=pascal

normalization:

The normalizer for the RTPOverview class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.

RTPStepOverview

description: Section containing a human readable overview of a certain step of the RTP process.

inherits from: nomad.datamodel.data.ArchiveSection

properties:

name type
duration float64 Duration of the step.
unit=second
pressure float64 Pressure in the RTP chamber during the step.
unit=pascal
step_ar_flow float64 Argon flow rate used during the step.The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
step_n2_flow float64 Nitrogen flow rate used during the step. The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
step_ph3_in_ar_flow float64 Phosphine flow rate used during the step.The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
step_h2s_in_ar_flow float64 H2S flow rate used during the step.The unit "cm^3/minute" is used equal to sccm.
unit=meter ** 3 / second
initial_temperature float64 Temperature at the beginning of the step.
unit=kelvin
final_temperature float64 Temperature at the end of the step.
unit=kelvin
temperature_ramp float64 Rate of temperature increase or decrease during the step
unit=kelvin / second
step_ph3_partial_pressure float64 Partial pressure of PH3 during the annealing plateau of the RTP process.
unit=pascal
step_h2s_partial_pressure float64 Partial pressure of H2S during the annealing plateau of the RTP process.
unit=pascal
step_n2_partial_pressure float64 Partial pressure of N2 during the annealing plateau of the RTP process.
unit=pascal
step_ar_partial_pressure float64 Partial pressure of Ar during the annealing plateau of the RTP process.
unit=pascal

normalization:

The normalizer for the DTUSteps class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.

DtuRTPSources

description: Information regarding the sources (gases) used in the RTP process.

inherits from: nomad_material_processing.vapor_deposition.cvd.general.CVDSource, nomad.datamodel.data.ArchiveSection

properties:

name type
sources str Automatically generated list of sources (gases) for this step
shape=['*']

normalization without further documentation

DTURTPSteps

description: Class representing each step in the RTP process.

inherits from: nomad_material_processing.vapor_deposition.cvd.general.CVDStep, nomad.datamodel.data.ArchiveSection

properties:

name type
step_overview RTPStepOverview sub-section
sources DtuRTPSources sub-section, repeats

normalization:

The normalizer for the DTURTPSteps class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.

DtuRTP

description: A synthesis method where a rapidly heated substrate is exposed to one or more volatile precursors, which react or decompose on the surface to produce a deposit. [database_cross_reference: https://orcid.org/0000-0002-0640-0422]

Synonyms: - rapid thermal chemical vapor deposition - rapid thermal CVD - RTCVD

inherits from: nomad_material_processing.vapor_deposition.cvd.general.ChemicalVaporDeposition, nomad.datamodel.metainfo.plot.PlotSection, nomad.datamodel.data.EntryData

links: http://purl.obolibrary.org/obo/CHMO_0001328

properties:

name type
lab_id str The ID of the run. Format: user_number_RTP.
location str location of the experiment.
default=DTU; IDOL Lab
log_file_eklipse str Cell to upload the gases log file from the RTP process.
log_file_T2BDiagnostics str Cell to upload the temperature log file from the RTP process.
samples_susceptor_before str Cell to upload the image of the samples on susceptor before theRTP process.
samples_susceptor_after str Cell to upload the image of the samples on susceptor after theRTP process.
used_gases str Gases used in the process.
shape=['*']
base_pressure float64 Base pressure when ballast is OFF
unit=pascal
base_pressure_ballast float64 Base pressure when ballast is ON.
unit=pascal
rate_of_rise float64 Rate of rise of the pressure in the RTP chamber during static vacuum
unit=pascal / second
chiller_flow float64 Chiller flow rate during the RTP process.
unit=meter ** 3 / second
input_samples DtuRTPInputSampleMounting sub-section, repeats
overview RTPOverview sub-section
steps DTURTPSteps The steps of the deposition process.
sub-section, repeats

normalization:

The normalizer for the RTP class.

Args: archive (EntryArchive): The archive containing the section that is being normalized. logger (BoundLogger): A structlog logger.