kSA MOS and Mini-MOS

Thin-film stress and wafer curvature measurement from reflective substrates and thin films.

k-Space provides three standard types of MOS systems:

(Note: 3-D models linked below require Windows® Internet Explorer® and installing eDrawings® when prompted.)

• Single Port MOS
  Normal incidence single port configuration (3-D model , 2-D pdf )
• Two Port MOS
  Two-port configuration, consisting of a laser housing (3-D model , 2-D pdf )and a detector housing (3-D model , 2-D pdf )
• Mini-MOS
  Single port, 1.33” CF mount or smaller, featuring tailored optics and mounting for commercial MOCVD systems where optical access and space are limited. (2-D pdf )

We also ofter custom mounts to accommodate any chamber configuration.
In addition the following options can be supplied:

• High Resolution Detector
  High Resolution CCD detector and frame grabber, offering 2x spatial resolution increase versus standard CCD.
• High Resolution Shaft Encoder
  12-bit encoder with PLC for TTL rotational triggering with 0.088 degrees resolution (4096 steps) and accompanying control software.
• Growth Rate Monitor
  Reflectivity-based monitoring providing real time growth rate, thickness, and optical
  constants (n,k).
• Multi-Wafer
  Multi-wafer capability for separate data analysis for each wafer on a rotating platen.
• Thermal Scan
  Thermal scan capability providing automatic temperature monitoring and control.

k-Space references are a compilation of published papers that either offer a review of the techniques used by the kSA MOS, or specifically use the kSA MOS for work within the paper.

In situ measurement of the internal stress evolution during sputter deposition of ZnO:Al

S. Michotte, J.Proost

Solar Energy Materials & Solar Cells 98 (2012) 253–259

Periodic variation of stress in sputter deposited Si/WSi2 multilayers

Kimberly MacArthur, Bing Shi, Ray Conley and Albert T. Macrander

Applied Physics Letters 99, 081905 (2011)

On the use of a multiple beam optical sensor for in situ curvature monitoring in liquids

Q. Van Overmeere, J.-F. Vanhumbeeck, and J. Proost

Review of Scientific Instruments 81, 045106, 2010

The NSLS-II Multilayer Laue Lens Deposition System

Ray Conley, Nathalie Bouet, James Biancarosa, Qun Shen, Larry Boas, John Feraca, Leonard Rosenbaum

SPIE 2009

Growth stresses and cracking in GaN films on (111) Si grown by metal-organic chemical vapor deposition. II. Graded AlGaN buffer layers

Srinivasan Raghavan and Joan Redwing

Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University

Journal of Appl. Physics, 98, 023515, 2005
 

Growth stresses and cracking in GaN films on (111) Si grown by metal-organic chemical vapor deposition. I. AlN buffer layers

Srinivasan Raghavan and Joan Redwing

Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University

Journal of Appl. Physics, 98, 023514, 2005
 

Evolution of surface morphology and film stress during MOCVD growth of InN on sapphire substrates

Abhishek Jain, Srinivasan Raghavan, Joan M. Redwing

Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University

Journal of Crystal Growth 269 128-133, 2004
 

In situ stress measurements during MOCVD growth of AlGaN on SiC

Jeremy D. Acord, Srinivasan Raghavan, David W. Snyder, Joan M. Redwing

Materials Research Institute and Applied Research Laboratory, The Pennsylvania State University

Journal of Crystal Growth 272, 65-71, 2004
 

Correlation of growth stress and structural evolution during metalorganic chemical vapor deposition of GaN on (111) Si

Srinivasan Raghavan, Xiaojun Weng, Elizabeth Dickey, and Joan M. Redwing

Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University

Appl. Phys. Lett. Vol. 88, 041904, 2006
 

Effect of AlN interlayers on growth stress in GaN layers deposited on (111) Si

Srinivasan Raghavan, Xiaojun Weng, Elizabeth Dickey, and Joan M. Redwing

Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University

Appl. Phys. Lett. Vol. 87, 142101 2005
 

Real-time strain evolution during growth of In_xAl_1-xAs/GaAs metamorphic buffer layers

C. Lynch, R. Beresford, and E. Chason

Brown University

J. Vac. Sci. Technol. B 22, 1539 2004
 

Evolution of the growth stress, stiffness, and microstructure of alumina thin films during vapor deposition

Joris Proost and Frans Spaepen

Harvard University

Journal of Appl. Phys., Vol. 91, No. 1, 1 Jan. 2002
 

Intrinsic stress development in Ti-C:H ceramic nanocomposite coatings

B. Shi and W. J. Meng - Louisiana State University

L. E. Rehn and P. M. Baldo - Argonne National Laboratory

Appl. Phys. Lett., Vol. 81, No.2, 8 July 2002
 

Stress evolution during metalorganic chemical vapor deposition of GaN

S. Hearne, E. Chason, J. Han, J. A. Floro, J. Figiel, and J. Hunter, H. Amano, I. S. T. Tsong

Appl. Phys. Lett. Vol. 74, no. 3, 1999
 

Real Time Measurement of Epilayer Stain Using a Simplified Water Curvature Technique

J. A. Floro, E. Chason, and S. R. Lee

Sandia National Laboratories
 

Stress Evolution in Sputtered FCC Metal Multilayers

Vidya Ramaswamy, William D. Nix, and Bruce M. Clemens

Stanford University
 

Stress Evolution During Growth of Sputtered Ni/Cu Multilayers

Vidya Ramaswamy, Bruce M. Clemens, and William D. Nix

Stanford University
 

Stress and Defect Control in GaN Using Low Temperature Interlayers

Hiroshi Amano, Motoaki Iwaya, Takayuki Kashima, Maki Katsuragawa, Isamu Akasaki, Jung Han, Sean Hearne, Jerry A. Floro, Eric Chason and Jeffrey Figiel

Appl. Phys. Part.1, Vol. 37, no.12B, 1998
 

Measuring Ge segregation by real-time stress monitoring during Si 1-xGe x molecular beam epitaxy

J. A. Floro and E. Chason

Appl. Phys. Lett 69, 1996 (p. 3830)

Real-time analysis of 2D thin-film stress and curvature. An arbitrary number of laser spots, are tracked simultaneously, yielding time-resolved radius of curvature measurements, mean differential spot spacing and stress. The mean differential spot spacing is used to calculate time resolved strain.

During analysis user input of physical geometry and substrate parameters yields calculation of radius of curvature or relative stress as a function of time, temperature, or other user configurable input. 

Accurate film thickness determination can be achieved using reflected intensity oscillation data recorded during growth. Beam intensity variations are used to determine growth rate, real-time thickness, roughness and optical constants (n,k).

Optionally a thin-film deposition recipe can be generated so multiple layers can be properly fit in real-time. Each layer in the recipe will have a user-estimated n, k, and G value. Each layer can be triggered via an external trigger signal or can be time-based. Additionally the deposition rate, thickness, n, and k can be output to analog output channels for input into a process control system.

MOS includes the capabilty for automatic laser spot detection and for automatic laser power control. The power control is important to ensure that the detector does not become saturated as surface reflectivity changes.

One application of the MOS system is monitoring curvature/stress during high temperature annealing. The thermal expansion inherent in most heater stages causes significant angular displacement of the heater stage and sample. The effect of the displacement is that the reflected beam array slowly drifts off the CCD during the temperature ramp. Compensation for this drift is made using servo-motor control of an optical flat mirror to provide fully automated tracking capability through the MOS software.

kSA MOS flyer

Two-page flyer describing the features of the kSA MOS
 

kSA Mini MOS flyer

Two-page flyer describing the features of the kSA Mini MOS for MOCVD reactors

kSA MOS Application Notes are documents written about a specific component or components of the kSA MOS thin-film stress system. These documents are designed to explain details of the kSA MOS capabilities and aid the user in maximizing the utility of the system. k-Space User Manuals are available for download as well by contacting us.

Note that some documents contain proprietary information, and therefore are password protected. If you are a k-Space customer, please email us requesting a username and password, and we will respond via email with a proper username and password, allowing you access to the document.

There are no application notes at this time.

k-Space white papers are documents that describe a technology or technologies utilized by a k-Space product. White papers may also include calibration procedures, application to various technologies, or comparisons with similar products.

Note that some documents may contain proprietary information, and therefore are password protected. If you are a k-Space customer, please email us requesting a username and password, and we will respond via email with a proper username and password, allowing you access to the document.

Curvature-based Techniques for Real-Time Stress Measurement During Thin Film Growth (06-26-02)

Jerrold A. Floro and Eric Chason

Sandia National Laboratories
 

Use of kSA MOS System for Stress and Thickness Monitoring during CVD Growth (05-17-00)

Eric Chason

Brown University
 

A Laser-Based Thin-Film Growth Monitor (04-25-02)

Charles Taylor, Darryl Barlett, Eric Chason, and Jerry Floro

The Industrial Physicist, March 1998 (p.26-30)
 

Resolution and sensitivity of stress measurements with the k-Space Multi-beam Optical Sensor (MOS) System (05-19-04)

Eric Chason

Sandia National Laboratories