INFICON MDC-260 Thin Film Deposition Controller - Manual (Page 53)

MDC-260 DEPOSITION CONTROLLER
PROGRAMMING AND CONTROLLER SETUP 4-17
1. Material Name (A ten character material name)
The material name parameter allows you to either use the keypad to type in a
name, or pick a name from the materials already stored in the material library.
To pick a material from the material library, highlight the material parameter and
press the Right-arrow key. This will display a complete list of materials that are
stored in the MDC-260. To pick a material, highlight that material and press
Enter key. Once a material is chosen, the stored values for the density and
acoustic impedance for that material are automatically entered into their
respective parameters.
2. Sensor# (1 to 2)
This parameter defines the sensor input that will be used for this material. Choose
between 1 and 2. The default setting is 1.
3. Crystal# (1 to 16)
This parameter defines the primary crystal used to monitor this material. This
parameter cannot be greater than the Number of Crystals parameter in the Sensor
Setup screen. The default setting is 1.
4. Source# (1 to 2)
This parameter defines the source output number that will be used for this
material. Choose between 1 and 2. The default setting is 1.
5. Pocket# (1 to 16)
This parameter defines the pocket number that contains this material. This
parameter cannot be greater than the Number of Pockets parameter in the Source
Setup screen. The default setting is 1.
6. Density (0.80 to 99.99 gm/cm
3
)
This parameter provides the material density so that the controller can calculate
and display the physical film thickness. If the film density is known it should be
used. A list of the more commonly used film densities is presented in Table 10-1.
As a first approximation, bulk material density can be used in programming.
Empirical calibration of this parameter is described in Section 10.5.1.
7. Acoustic Impedance (0.50 to 59.99 gm/cm
2
/sec)
This parameter is the acoustic impedance of the material. The acoustic
impedance of the deposited film is required by the MDC-260 in order to
accurately establish the sensor scale factor when the sensor crystal is heavily
loaded. If the acoustic impedance of the film material is known, it can be entered
directly in units of 10
5
gm/cm
2
sec. In most cases the acoustic impedance of the
bulk material can be used and can be obtained from The Handbook of Physics or
other source of acoustic data. The shear wave impedance should be used. The
shear wave acoustic impedance can be calculated from the shear modulus or the
shear wave velocity and the density by using the following equation: