Pacific Nanotechnology Inc. - Printable version

Included with the system is a master computer, software, an electronic controller, and an AFM stage. The automated X-Y stage accepts wafers up to 6” (150 mm) in diameter and 0.33” (8.5 mm) thick. With this unique stage it is possible to adjust the angle of the probe sample under computer control. Nano-IM™ 6x6 software runs on the Windows XP™ operating system.

The Nano-IM™ 6x6 stage easily fits on a table top and can be operated with high resolution results in a normal laboratory environment.

The stage is designed to maximize flexibility in the types of samples that are accommodated as well as make the setup and alignment of the AFM head as easy as possible.

The stage includes:
• AFM Head
• X-Y Sample Stage Translator
• Sample Stage
• Z Motion Control

All power for the stage is received from the electronic controller via a series of 8’ (2.5 m) long cables. Operation of the stage requires an air pressure line and a vacuum source.

AFM Scanner

The Nano-IM™ 6x6 AFM scanner uses the standard light lever method for monitoring the motion of a cantilever as it is raster scanned across a surface. The scanner is a patented, compact design that offers a direct internal scanner calibration. A hollow pivot scanner facilitates a direct view with a video optical microscope.

Alignment of the AFM sensor is achieved with four adjustment screws that are easily accessed at the front of the AFM head. Two of the adjustments move the laser into position on the cantilever. Two other adjustments move the photo-detector into the path of the reflected laser beam.

Motorized Z Approach

The Nano-IM™ 6x6 includes a unique three motor approach system that is used for moving the AFM probe to the sample for scanning. Each motor has .33” (8.5 mm) of motion, is independently controlled and includes position sensors. The software for activating the Z approach motors is included with the SPMCockpit™ software.

Sample Stage

All types of wafers and disks are accommodated on the Nano-IM™ 6x6 sample stage. After a wafer is placed on the stage, a vacuum is employed to hold the wafer rigidly to the stage. At the surface of the stage are vacuum rings for 2” (50 mm), 4” (101 mm), and 6” (152 mm) diameter wafers. Each of the vacuum rings may be independently activated. Samples having a thickness of up to 0.33” (8.5 mm) may be placed on the sample stage for AFM imaging. The sample stage may be rotated by 360° to image an entire wafer with the AFM without removing the wafer from the stage.

X-Y-Z Sample Stage Translation

The Nano-IM™ 6x6 has a unique design for the X-Y stage translation mechanism. The X-Y motion is generated by stepper motors at the back of the granite support in a position that is not visible, is easily kept clean, and is safe.

The stage has a 6” (150 mm) motion in one direction and a 7” (178 mm) motion in the other. Wafers are easily loaded on the sample stage with software control. Motion of the sample in the Z direction is generated by three motors located inside the gantry. These three motors are useful not only for probe approach, but also for leveling the stage and for precise control of the sample/probe angle.

Software is used for energizing the X-Y sample stage. The window for controlling the stage is illustrated here. The position and rate of travel are software controlled.

Video Optical Microscope

A color video microscope is essential for locating features on a surface for scanning in an AFM. The Nano-IM™ 6x6 AFM has a motorized zoom and focus video microscope controlled by either Nano-IM™ 6x6 AFM software or the system’s trackball. There is a manual control of the X-Y position of the microscope objective for centering the image of the cantilever in the video microscope image.

Special Nano-IM™ Configurations

The Nano-IM™ AFM is offered to accomodate scanning of non-standard sample shapes and sizes. The AFM scanner is incorporated into a support structure, or gantry, that may be mounted on a customized stage so that almost any size and shape of sample may be scanned successfully.

As an example, Figure 6 illustrates a Nano-IM™ configured for a 12 inch wafer. This stage can also accomodate samples up to 18 inches in diameter.

Nano-IM™ 6x6 Modes

The Nano-IM™ 6x6 system comes with most standard AFM scanning modes. All are controlled by software and work on the provided head. The included modes are:

Controller and Master Computer

The master computer, required for acquiring and analyzing images, is a standard PC type computer. Connection of the computer to the control unit is with a standard Ethernet connecter. Specifications for the computer system are improved on a routine basis when improved computer systems are made available.

Force Sensor	Light Lever
Detector	4 Quadrant Photo-detector
Laser	650 nm diode – 25 micron spot size
Laser Adjustment	80 TPI
Probe Holder	Universal Adapter
Probe Types	Pre-mounted - Magnetic
XYZ Calibration Sensors	Inductive – 1 nm resolution
Z Scanner Type	Piezoelectric Ceramic – Direct
Z Range	8 Microns
Z Noise	<0.06 nm*
Z Linearity	< 1 %
Z out of plane motion	< +/- 30 nm
XY Scanner Type	Flexure
XY Range	90 Microns(180 or 360 microns optional)
XY Linearity	< 1 %
XY Noise	< 0.01 nm (open loop)
XY, XZ, YZ Crosstalk	< 1 %
Probe Electrical Connector	Isolated 5 Connector

Scan DAC	16 Bits
XYZ board – Primary and Secondary • Digital Zoom/Offset • Analog Zoom • Z High Voltage • Z Sample/Hold • PID Control • Phase/Amplitude • XY High Voltage • XY Sensor Feedback	16 Bits 4 bits on High Voltage -20 to 140 Volts 20 Bits Analog 400 Mhz Clock/32 Bit Frequency Control +X,-X +Y,-Y (-20 to 140 Volts) Analog PID Control
User Access	Connector for Signal Access Console
Internal Digital Control • CPU • Operating System • Communications Protocol • Memory	Pentium Linux TCP/IP RAM/Disk Drive
Motor Driver Board • Number of Motor Drivers • Motor Type • Control • Additional Function	7 Stepper Microprocessor Light Intensity Control

XY Stage Range • X • Y	150 mm 150 mm
XY Stage Step Size	4 um
XY Stage Accuracy	< 10 um
Z Motor Range	8 mm
Z Motor Step Size	162 nm
Sample Puck • Hold Down • Height • Maximum Sample Diameter	Magnetic 30 mm 100 mm
Optical Microscope • Resolution • Zoom Ratio • Field of View	1.5 u 4:1 140 x 190 u at Maximum Zoom
Probe Exchange	Flip Up

Computer Monitor	19” LCD
Video Monitor	19” LCD
Accessories	Mouse, Keyboard, Trackball
Computer: • Type • Operating System • Memory • Disk Drive AFM Software: • Acquisition • Display Video Converter	IBM PC Microsoft Vista > 1 Gigabyte > 200 G Bytes EZ Mode™, X’ert™ Mode AFM Analysis, and NanoRule+™ NTSC – SVGA

Vacuum Rings	2” (50.8 mm), 4” (101.59 mm), 6” (152.39 mm)
Sample Thickness	< 0.3” (8 mm)
Sample Diameter	6” (150 mm) full, < 12” (304.8 mm) partial
Attachment	Vacuum