Control and analysis software: Fab integration with EpiNet and PocketGuard

EpiNet 2017 is a software for control, analysis and optimization of epitaxial processes in production and development of LEDs, laser diodes, VCSEL, HEMT, HBT and other electronic and optoelectronic devices.
The software extracts key figures about wafers’ behavior during growth. In run-to-run control and in statistical process control, these key figures are used to improve yield and process capacity. EpiNet 2017 can be integrated into automated fab workflow providing from simple plain-text files to sophisticated live SECS/GEM integration.

Customer's benefits:

  • In-situ process control with ex-situ accuracy even for very thin layers
  • Control of complex production processes on operator level
  • Fast in-spec / out-of-spec indication for stop or go decisions
  • High automation saves operator‘s time, eliminates error sources and makes in-situ control easy without training
  • Engineer’s access level for sophisticated data analysis
  • High customization

EpiNet can be integrated horizontally and vertically into the fabs' logical structure using a wide range of protocols and interfaces, starting with low-end analog and digital signals over field buses to the most complex high level SEMI standards like SECS / GEM. This allows to connect to host systems such as MES (manufacturing execution system) and EES (equipment engineering system) using SECS / GEM and EDA / Interface A based on AIS FabLink.
EpiNet provides process-aware algorithms superior to any standard production control system. It can provide process information not available to the growth equipment like complex uniformity information on each wafer. Information which then is intelligently compacted into data that can be handled and analysed by statistical systems. Learn more about Advanced Process Control (APC) with EpiNet

EpiNet features

Operator's view: PocketGuard

  • Quick check of all monitored wafers during the run at one glance
  • All wafers are color-coded by user-defined in-spec / out-of-spec criteria and visualized as they are positioned on the susceptor
  • In-spec / out-of-spec criteria can be set for all LayTec‘s analysis features
  • Customer can easily set up procedures for corrective actions based on PocketGuard information ###NOHIDE###

Wafer-to-Wafer view for post-run analysis

  • Analysis results for all wafers shown in separate web  charts (polar charts)
  • Easy comparison of wafers for run homogeneity check
  • Fast detection of outliers – wafer zones that are out of specification limits (red circle) or control limits (yellow circles)

Color plots and line scans

  • Color plots (left): time and space-resolved measurements for quick fingerprinting and visualization
  • Line scans (low right) show wafer homogeneity during growth
  • Time-resolved trainsients (upper right) are the basis for detailed analysis of growth performance (see Transient view below)###NOHIDE###

Expert analysis: Transient view

  • Complex data comparison of critical process parameters down to single data points across zones, wafers and runs
  • Transients can be segmented manually or automatically into growth steps
  • Automated analyses of any step to extract process information from raw data (e.g., composition, growth rate etc.)
  • Pre-configuration of analyses algorithms as recipes for repeated or automated use###NOHIDE###

Configuration panel: customized run type management

  • Visualization of susceptor geometry for setting measurement zones (available for single and multi-pocket configurations)
  • Wafer-specific settings for each pocket: susceptor material, pocket material, wafer substrate, thickness and surface condition

For Operators:

  • Use of pre-configured analysis recipes
  • Automated start of in-situ measurements###NOHIDE###

Improved nk data base for III-Nitrides

Alongside with our high-accuracy high-temperature nk database for Arsenides and Phosphides, which enables  in-situ process control of layer thickness and composition at the same level of accuracy as XRD or PL, LayTec has developed an improved nk database for the III-Nitrides as part of the latest version of our EpiNet software. These high accuracy nk data in conjunction with Pyro 400 wafer temperature control opens a pathway to a more comprehensive and direct SPC of III-Nitride based manufacturing on Patterned Sapphire Substrates (PSS), silicon and, most importantly, on GaN wafers.
As an example, you can find some measurement results in the talk of Mr. Christoph Berger "In-situ metrology during growth of novel nitride-based semiconductor Bragg mirrors":  Download the PDF of the talk.

Analysis of nanometer scaled quaternary films with EpiNet 2016

LayTec's new release of the control and analysis software EpiNet2016 offers completely new analysis features for our customers interested in high-accuracy statistical process control (SPC) of related device growth processes. Fig.1 gives an example:

Fig. 1: Screenshot of the EpiNet 2016: data analysis of an InGaAsP/InP device structure on InP(001): the thickness of the three very thin InGaAsP layers in steps 2, 6, 10 is: 28.5
nm, 48.7nm and 100.3nm respectively. The table in the lower part of the figure gives the sequence of analysis functions for routine and automated SPC of this device growth process.
The thickness of very thin InGaAsP layers in a device stack grown in an AIXTRON Planetary Reactor® on InP(001) is determined by a well selected set of automated analysis operations. First, several InP layers are utilized for permanent in-situ high-accuracy re-calibration of all reflectance channels (yellow lines) in long lasting epi runs. Second, the lattice matching of the quaternary layers is verified by wafer bow analysis (not shown). Third, the composition of the quaternary material is determined at the thick InGaAsP layer in step #14. And finally, based on this information, the thickness of the thin InGaAsP layers in steps #2, #6 and #10 is accurately measured by double-wavelength thickness analysis.

For better understanding of growth processes, LayTec offers related training courses for process engineers and quality managers. To learn more, please contact or call our sales engineer +49 30 89 00 55-0.

Product Information

  • User-friendly visualization of measured data
  • Active real-time GOLDEN RUN analysis
  • Toolbox of diagnostic algorithms for all relevant process steps
  • Flexible configuration for epi fab-wide SPC (statistical process control) and FDC (fault detection & classification)
  • Tight in-house control of your confidential recipes
  • Full linescan capability
  • Integration into growth system software is possible
  • Interactive and recipe-controlled analysis of growth rate, layer thickness and optical constants
  • Display of measurements as time-resolved data sets, line scans and color plots



EpiNet 2017 Flyer

Patterned Sapphire Substrates (PSS): Fast and easy growth analysis with EpiNet