kSA ICE - Integrated Control for Epitaxy
Product Specifications
The k-Space Integrated Control for Epitaxy system (ICE) is an integrated in-situ metrology tool designed specifically for MOCVD, and is the result of 15 years of in-situ monitoring development and refinement by k-Space. Integrated into a single optical head, kSA ICE provides real-time temperature, reflectivity, and curvature/bow measurement during MOCVD deposition. The patented curvature/bow measurement technique is performed by monitoring the substrate curvature with an array of parallel laser beams, detecting their spacing via a CCD detector. The same laser is used in combination with a high speed photo detector to monitor and fit the surface reflectivity, yielding real-time film thickness, growth rate, and optical constants (n, k). The patented temperature measurement technique is actually multiple, independent measurements of the pocket temperature via blackbody spectrum analysis and broadband pyrometry analysis, and the absolute GaN film temperature via band-edge thermometry. The system is ideally suited for real-time feedback to process control systems via a TCP/IP interface.
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
1
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy kSA ICE REAL-TIME ANALYSIS CAPABILITIES kSA Technology
Technology Description
Blackbody Temperature
Measures the spectral blackbody radiation signature of a sample across a wide wavelength range and then curve fits the response in real time to Planck’s equation to determine temperature. Self-calibrating technique – no temperature reference required.
Broadband Pyrometry Temperature
Measures the collected blackbody radiation intensity of a sample over a wide wavelength range and integrates the signal into standard pyrometry equations to determine temperature.
Semiconductor Band-Edge Temperature (BLUE ICE Option)
Measures the direct semiconductor optical absorption shift with temperature (band gap dependence on temperature) and uses kSAgenerated calibration files to determine absolute film temperature (not pocket temperature).
Spectral/Static Film Thickness and Growth Rate (BLUE ICE Option)
Analysis of extrema positions in the below gap interference spectra. Thickness and growth rate of the film can be determined to within 1% accuracy, in real time during deposition.
Surface Roughness (BLUE ICE Option)
By monitoring the above gap diffuse scatter signal, kSA Blue ICE can provide a qualitative measurement of surface roughness.
Wafer Curvature and Bow
Real-time plotting of intensity, differential spot spacing, curvature/radius of curvature, and wafer bow. An arbitrary number of laser spots, user configured, are tracked simultaneously, yielding time-resolved radius of curvature/bow measurement.
Reflectivity and Growth Rate
Reflected laser intensity data recorded during growth provides accurate growth rate and optical constant determination with as little as 60nm of material deposition. Real-time update of optical constants (n, k), deposition rate, and film thickness are provided. Ability to generate a thinfilm deposition recipe, so multiple layers can be properly fit in real-time. Each layer can be triggered via an external trigger signal or can be timebased.
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
2
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy STANDARD HARDWARE LAYOUT
INTEGRATED OPTICS kSA ICE uses customized optics for optmizing each signal for highest performance required for the specific measurement and wavelength range. The curvature/bow section utilizes an etalon to generate a 1-D array of parallel laser beams from a single beam laser source. The reflectivity section uses a high efficiency beam splitter and collimating optics to ensure high speed and high S/N reflectance signal, while the temperature section uses hot and cold mirror optics to ensure signals are optmized in specific wavelengh ranges, while not impacting the other measurements. All optics are rigidly mounted to reduce vibrational noise. All components are stabilized and/or temperature controlled to maximize lifetime and signal stability during measurements.
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
3
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy DYNAMIC SIGNAL INTENSITY CONTROL (kSA PATENTED) During film deposition, the surface reflectivity will change due to changes in material properties and/or surface morphology. k-Space has developed and patented a software-based algorithm for dynamically adjusting the laser and/or detector integration times to maintain the highest S/N during these changes. This feature comes standard on all kSA ICE systems.
DYNAMIC PLATTER SYNCHRONIZATION (kSA PATENT PENDING) k-Space has developed the ability to synchronize to the rotating platen by analyzing the reflected laser signal in real-time and internally generating the appropriate trigger signals for all devices. This alleviates the need for a hard trigger source, and solves the problem of “slipping” platens that are not rigidly attached to the rotation shaft.
kSA ICE OPTICS HEAD OPTIONS Chamber mount interface designs are available for all commercial MOCVD reactors. Generally, two orientations of the optics head are available – vertical and horizontal.
Vertical kSA ICE Enclosure
k-Space Associates, Inc.
Horizontal kSA ICE Enclosure
Dexter, MI USA | Tel: (734) 426-7977
4
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy
With kSA Blue ICE Option
k-Space Associates, Inc.
With kSA Blue ICE Option
Dexter, MI USA | Tel: (734) 426-7977
5
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy SYSTEM DETAILS Curvature Rotation Speed Range Measurement Resolution
Calibration Type Cable Type and Length
Reflectivity
Temperature
0-2000 RPM Up to 20km
0.2%
kSA-supplied calibration mirror(s) or wafer 10m CAT5 Ethernet cable
Sapphire or Silicon wafer
+/- 0.2C (pocket temperature, > 400C) +/- 0.5C (MQW film temperature – Blue ICE) None required (self-calibrating)
20 ft. power/data cable
1. 2.
Sensor Type
Interline transfer CCD, removable cover glass, selectable electronic shutter, on-chip integration capability
Amplified silicon photo detector
1.
2.
Light Source
Laser Wavelength: 660nm nominal Laser Output Power: >30 mW, measured directly at laser output. Beam Geometry: Circular Gaussian output with integrated long focal length lens cell Operation Mode: Constant current output Stability: ≤ 0.2%
Spot or Collection Size on Wafer Sensing area:
Up to 1 x 4 spot array 2-4mm 2-4mm Each spot is 0.8mm diameter 2/3” format (8.8mm x 6.6mm) 12-bit 56 dB or better 60dB or better 16-bit 1us to 20msec (patented Up to 500 kHz 0.375ms to 20msec typical auto-intensity control) (patented auto-intensity control) 10-140Hz typical 10-140Hz typical 10-140Hz typical. 3-24V input or Optical via kSA ICE Laser Module 2X 0-10V Analog Output (DB-9 Connector) 2X Digital Triggering Inputs (DB-9 Connector) 1X Rotational Trigger Input (BNC) TCP/IP Interface Windows 7 Professional 64-bit, QuadCore Processor, 4GB DDR3 SDRAM, 500GB (minimum) SATA Hard Disk, 512MB DVI+HDMI Video Card, Gigabit Ethernet, USB2, USB3, DVD +/-RW, 22-inch Flat Panel Monitor, USB keyboard, USB optical mouse, 22” flat panel monitor
S/N: Exposure Time: Data Acquisition Triggering: External Communications and I/O Interface Computer Specifications
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
6
1. 2.
10m uLOH Fiber with steel jacket Blue ICE Option: HOH Fiber with steel jacket (bifurcated) 870-1670nm 128 element, temperature stabilized NIR InGaAs Spectrometer Blue ICE Option: 350-600nm 512 element VIS Si-CCD Spectrometer None Blue ICE Option: 300W Xenon Light Source
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy kSA ICE INTEGRATED SOFTWARE DESCRIPTION (VERSION 1.3)
User-friendly Windows-standard environment with extensive error checking and file handling. Data storage in ASCII, Excel or binary file formats facilitate alternative data analysis by user. Full real-time display of all pertinent acquisition parameters, at all marker positions.
High-quality 2D and 3D graphics for data display. Numerous image and graphics editing capabilities, including false coloring using pre-loaded or user-defined color palettes, and label editing. Transport of graphics directly to Windows clipboard or exported to Windows Metafile, Tiff or Bitmat format.
Full TCP/IP data exchange capability for real-time transfer of any or all measurement parameters to external reactor control software. Full support and seamless integration with Axiom interface for Veeco reactor users utilizing Nexus control software.
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
7
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
kSA ICE - Integrated Control for Epitaxy MULTI-WAFER TRACKING AND MARKER POSITIONS kSA ICE uses signal intensity changes in the wafer and carrier to visually trace and define wafer positions during rotation. The user is then able to accurately place measurement “markers” at any position to enable real-time monitoring at that location. Wide markers are available when averaging over a particular wafer or carrier area is desirable for process control. Up to 180 markers may be placed within or across multiple wafers.
k-Space Associates, Inc.
Dexter, MI USA | Tel: (734) 426-7977
8
[email protected] |
www.k-space.com
October 2012 kSA ICE Product Specifications
