SID-142 Thin Film Deposition Controller SQM-142 Deposition Control Card SQS-142 Deposition Control Software Version 2.16 User’s Guide © Copyright Sigma Instruments, Inc.
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Warranty Information This Sigma Instruments product is warranted against defects in material and workmanship for a period of 1 year from the date of shipment, when used in accordance with the instructions in this manual. During the warranty period, Sigma Instruments will, at its option, either repair or replace products that prove to be defective.
Table of Contents Chapter 1 1.0 1.1 1.2 1.3 1.4 SID-142 Introduction...................................................................................1-1 SRC Series Computer ................................................................................1-1 SQM-142 Deposition Control Card ..............................................................1-2 SQS-142 CoDeposition Control Software.....................................................1-2 Digital I/O ................................................
Chapter 3 SQS-142 Software (continued) 3.4.4 System .................................................................................................3-17 Sensors.............................................................................................3-17 Sources.............................................................................................3-18 Digital I/O..........................................................................................3-19 PLC Setup...............................
Chapter 1 Introduction 1.0 Introduction This manual covers both the hardware and software associated with the SID-142 Thin Film Deposition Controller. The SID-142 consists of four main elements, integrated into a complete deposition control system: SRC Series Rack-mount Computer SQM-142 PC Card(s) SQS-142 Windows CoDeposition Software PLC for Digital I/O (option) While the focus of this manual is on the SID-142 Controller package, it also covers each of these components separately.
Chapter 1 Introduction 1.2 SQM-142 Deposition Control Card Sigma’s SQM-142 card installs in a computer ISA slot, and provides the interface to the vacuum deposition system. Each card measures up to four quartz sensors via BNC inputs, and supplies the control signal for two evaporation sources via a dual phone plug output. Up to two cards can be installed in a computer, creating an eight input, four output, codeposition controller.
Chapter 1 Introduction The six SoftKeys provide easy access to the common operating functions. A single tabbed dialog box provides all of the settings required for a thin film process. Material parameters, sensor/source setup, pre/post conditioning, and error conditions are all visible on a single screen. Process settings, numeric data, and graphical displays are displayed during all phases of deposition. The SQS-142 software stores process parameters in a Microsoft Access compatible database.
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Chapter 2 Quick Start 2.0 Introduction This section covers the minimum system connections and initial setup required to run the SID-142 Deposition Controller. Consult later chapters of this manual for more detailed setup and operational instructions. 2.1 Installation All electrical connections to the SID-142 are made at the back panel of the instrument. WARNING: Care should be exercised to route SID-142 cables as far as practical from other cables that carry high voltages or generate noise.
Chapter 2 Quick Start 2.2 Front Panel SoftKeys TouchPad Control Knob Floppy Disk Front Panel Controls SoftKeys Provide basic instrument operations within the SQS-142 deposition program. The SoftKeys are functional only in programs written specifically for the SRC computer. TouchPad Provides mouse functions in all Windows programs, including the SQS-142 software. Move your index finger along the touchpad surface to move the mouse.
Chapter 2 Quick Start 2.3 Program Startup This section will start the SID-142 and run the SQS-142 deposition control program. Power On the Computer Move the rear panel power switch on the SID-142 to the On (|) position. Start the Program The SID-142 will boot Windows from the internal hard disk and start the SQS-142 deposition program. If the SQS-142 program does not start automatically, use the touchpad to double-click the desktop icon.
Chapter 2 Quick Start 2.4 Single-Layer Process Setup A thin film deposition process consists of one or more layers of material evaporated onto a substrate. Let’s build a simple single-layer process. Open Process Edit Use the touchpad to click on the “Edit” menu selection along the top of the display, then click “Process.” The Process Edit dialog will display the setup for the last process run. To better understand process setup, see section 3.4.1.
Chapter 2 Quick Start The diagram below illustrates a complete deposition cycle for a single layer. Refer to this diagram as we set the remaining process setup parameters. Edit Rate Ramps It may be desirable to vary the deposition rate during a layer. For example, to deposit slowly at first, then more quickly once the initial material is deposited. Click the “Rate Ramps” tab, then click “Insert Ramp.” Adjust the “Start Thickness” to 0.400 kA, “Ramp Time” to 5 seconds, and “New Rate” to 15 A/s.
Chapter 2 Edit Deposition Quick Start Select the “Deposition” tab. This tab establishes the gain (P Term), time constant (I Term), and dead time (D Term) for your process. Set these values to 55, .7, and 0 respectively. Be sure Shutter Delay Enabled is not selected. Select Ignore for Control Error, and Continuous for Rate Sampling (see picture below).
Chapter 2 Quick Start Edit Source/Sensor Select the “Source/Sensor” tab. This tab contains parameters associated with the physical layout of your evaporation system. For now, be sure that “Output 1” is selected and “Max Power” and “Slew Rate” are set to 100. Set the “Tooling” value to 100. Leave the Source Index as it is. Save Edits Click “Close Form” or press the first SoftKey to save this onelayer process. If you are prompted “Do you want to change….,” answer Yes to make this the current process.
Chapter 2 Quick Start 2.5 Single-Layer Process Simulation If you have followed this chapter, you are ready to simulate a deposition process. Setup Displays Click the “View” menu and assure that these options are selected: Film Settings, Film Readings, and Automatic. Note that the settings “ribbon” along the right displays the preconditioning parameters you entered in the previous section. Start Process Verify that the top SoftKey label displays “START SIMULATE.
Chapter 2 Quick Start As shown below, the initial deposition rate was 10 A/s until a thickness of .400 kA. Then the deposition rate was ramped up to 15 A/s, and held until the desired final thickness of 1.000 kA is achieved. At this point, this single-layer process is finished. Deposition Phase with one Rate Ramp You should adjust the PID parameters on the setting ribbon, then Start/Stop the process several times to become familiar with their effect on control loop response.
Chapter 2 Quick Start 2.6 SoftKey Functions As you have seen, the SoftKey functions remain constant during deposition. Spend a few minutes to become familiar with each of these SoftKey functions. STOP/ABORT Starts the first layer of a process when START is displayed. Aborts the process when ABORT is shown. Once aborted, a process restarts at the pre-conditioning phase of the first layer.
Chapter 2 Quick Start 2.7 Multi-Layer CoDeposition Process Our final example builds on the previous sections. If you have modified the setup of your process, return to Section 2.4 and adjust the process to those values. When your single-layer process matches Section 2.4, complete these steps: Duplicate a Layer Open the Edit Process dialog. Click on Layer 1, click the “Layer” tab, then click “Copy Layer.” Now click “Paste Layer.” A duplicate Gold Sample film will be added as Layer 2.
Chapter 2 Quick Start Hint: It’s usually best to copy a layer, then paste several temporary layers of that type. Next, assign the films that you want to each of the pasted layers. When selecting films for codeposition, remember that each film in a codeposited layer must be assigned to a different source output! Now use “Cut Layer” on the temporary layers, and “Paste CoDep” to assign the film to the desired codeposition layers. Review this example until you are comfortable with these concepts.
Chapter 2 Quick Start 2-13
Chapter 2 Quick Start Edit Silver Conditioning Select the “Condition” tab and the Silver Sample layer. Set each parameter to the values shown below. Save Edits Click “Close Form” or press the first SoftKey to save this twolayer codeposition process. Answer Yes if it displays the “Do you want to change….” message box to make this the current process. Press the “START SIMULATE” SoftKey to start the first layer preconditioning phases. Note that two outputs are displayed for this codeposition layer.
Chapter 2 Quick Start Your response should be similar to the graph shown below (your vertical scale may be slightly different). The slight ringing on the waveforms indicates some further tuning may be desired. However, this is an example of a reasonably well tuned loop. At .400kA thickness, the Silver Sample deposition rate ramps down from 15A/s to 0. Similarly, at .400 kA thickness the Gold Sample film ramps to a higher deposition rate of 15A/s.
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Chapter 3 SQS-142 Software 3.
Chapter 3 SQS-142 Software 3.1 Installation The SQS-142 install program is available on CD-ROM or 3 ½” diskettes. The 3 ½” diskette install is also available by copying the contents of each of the CD-ROM “Disk” subdirectories to blank 3 ½” diskettes. To install the program, start Windows, then insert the disk or CDROM into your computer. Click Start, then Run, then type :Setup (where is the drive letter you are using). Click OK to begin installation, and follow the on-screen prompts.
Chapter 3 SQS-142 Software An Access Level is also associated with each User Name. The Access Level controls which software functions are available to a user. For example, only users with an Access Level of Supervisor can assign users. See the Security section of this chapter for information on setting up users. The remainder of this chapter covers the purpose and operation of each software function, arranged my menu selections. For a more “operational” approach, consult the previous Quick Start chapter.
Chapter 3 SQS-142 Software 3.3 File Menu Note: The current process must be stopped for the File menu to be available. Process: Used to select a process to be run from a list of processes in the database. If the process selected is different than the current process, you are prompted to confirm the change. Open Database: Selects the process database to be used for thin film deposition. A single process database may contain an unlimited number of processes, films, and materials.
Chapter 3 SQS-142 Software A number of “events” can trigger a data entry in the log file. “End Deposit Phase” records process data (rate, thickness, time, etc.) at the end of each layer’s deposit phase. Similarly, “End Each Phase” logs data at the end of each phase (conditioning, depositing, etc.). “I/O Events” logs data each time an external digital input or output changes. Finally, “Timed Logging” records data at the selected time intervals throughout the process. There are two formats for writing data.
Chapter 3 SQS-142 Software 3.4 Edit Menu 3.4.1 Edit: Process A process is a sequence of film layers. Multiple films deposited in the same layer are known as codeposition. A listing of each film in the selected process appears in the layers list box. Films in codeposition layers are listed with the same layer number. Select a layer to edit its parameters in the tabbed dialog boxes.
Chapter 3 SQS-142 Software Layer Tab The layer tab provides the capabilities needed to add and delete process layers, as well as to edit the film, rate & thickness for each layer. Normally each film in a process is run sequentially, as layers. Codeposition represents different films that are deposited concurrently with other films, in the same layer. Cut Layer: Removes the layer selected in the Layers list box from the process, and places the layer on the clipboard.
Chapter 3 SQS-142 Software Hint: It’s usually best to copy an existing layer, then paste several temporary layers of that type. Next, assign the films that you want to each of the temporary layers. When selecting films for codeposition, remember that each film in a codeposited layer must be assigned to a different source output! Now use “Cut Layer” on the temporary layers, and “Paste CoDep” to assign each temporary layer to the desired codeposition layer.
Chapter 3 SQS-142 Software Rate Ramps Tab Under PID control, rate ramps cause changes to the deposition rate over time. Each rate ramp has a starting thickness, an elapsed time to ramp to a new rate, and a new rate setpoint. Each process layer can have an unlimited number of rate ramps. Insert Ramp: Inserts a new rate ramp for the selected layer, at the selected position. Existing rate ramps are shifted down. Delete Ramp: Deletes the selected rate ramp.
Chapter 3 SQS-142 Software Deposition Tab The deposition tab contains parameters that directly affect the deposition phase of the process cycle. P Term: Sets the gain of the control loop. High gains yield more responsive (but potentially unstable) loops. Try a value of 50, then gradually increase/decrease the value to respond to step changes in rate setpoint. I Term: The integral term controls the time constant of the loop response. A small I term, say .
Chapter 3 SQS-142 Software Shutter Delay: It is often desirable to obtain deposition control before the substrate shutter opens. Enabling shutter delay requires that the system reach a specific control accuracy before deposition begins. If the accuracy is not reached, the process halts. If accuracy is reached, the substrate shutter opens and deposition begins when control accuracy has been maintained for 5 seconds. The Thickness reading is zeroed at the end of the shutter delay period.
Chapter 3 SQS-142 Software Condition Tab Before deposition begins, it is often necessary to precondition the source material. This places the system in a state to achieve rapid PID control when deposition begins. Ramp 1: Ramp power sets the power level desired at the end of the ramp phase, in % of full scale. Ramp time sets the time to ramp with a linear rate from the initial power to the Ramp power. Soak time sets the time the output remains at the ramp power level.
Chapter 3 SQS-142 Software Source/Sensor Tab The Source/Sensor tab controls the physical setup of the deposition system. Material: Selects the physical deposition material Max Power: The maximum output power allowed for the selected output. The full scale output voltage is a function of the deposition power supply input specifications, and is set in the SQM-142 setup. Max Power controls the maximum power that can be used by this process layer.
Chapter 3 SQS-142 Software In codeposition, a layer may have multiple films, with each material using a different output and sensor selection for control. However, a layer cannot have the same output assigned to more than one film. If you try to assign the same output to multiple films in a layer, an error message will be displayed. Also, reassigning a film to a different output may impact other stored processes.
Chapter 3 SQS-142 Software 3.4.2 Edit: Films The Edit Films dialog provides a subset of the functions of the Edit Processes dialog. The functions are those that pertain only to a specific film. NOTE: Edits to a Film will affect all processes and layers that use that film! Film: A drop down box that selects the film parameters displayed in the edit film dialog box. Defaults to the current process film. Rename: Edits the name of the selected film. New: Creates a new film.
Chapter 3 SQS-142 Software 3.4.3 Edit: Materials The Edit Material dialog provides the functions needed to build a materials database. In addition to the functions listed below, the main screen function keys provide capabilities to add/edit/delete materials. Material: Selects a material to edit. Density: Sets the density for this material. Material density has a significant impact on deposition calculations.
Chapter 3 SQS-142 Software 3.4.4 Edit: System Sets the operation of system Sensors, Sources, Digital I/O, and SQM-142 measurement card(s). Sensors Tab Sensor Name: A meaningful name assigned to sensors 1 to 4 in single card systems; 1 to 8 in two card systems. For easy display, keep the name to less than 8 characters. Sensor Output: The source output that a sensor is positioned to measure. Typically each sensor measures deposition from a particular source.
Chapter 3 SQS-142 Software Sources Tab Output Name: A meaningful name assigned to SQM-142 outputs 1 and 2 in single card systems; 1 to 4 in two card systems. For easy display, keep the name to less than 8 characters. Full Scale: The input voltage required by the deposition source power supply to produce 100% output power. Positive or negative full scale values are possible.
Chapter 3 SQS-142 Software Digital IO Tab The SID-142 uses an inexpensive PLC to provide digital I/O capabilities. The Digital I/O tab assigns deposition events (i.e. open shutter, start deposit, final thickness, etc.) to the available relays and inputs on the PLC. Note: Omron CPM series PLCs number relays from 10.00 to 10.07, then 11.00 to 11.07. These correspond to Relays 1 to 16 on the Digital I/O tab. Similarly, inputs 0.00 to 0.11 on the Omron PLC correspond to inputs 1 to 12 on this screen.
Chapter 3 SQS-142 Software If Dual Sensor is not selected (i.e. a single sensor), the relay contacts are closed when you are in a layer with the sensor enabled. As an example, let’s say you have sensors 1 and 3 enabled for Film 1 and sensors 2 and 4 enabled for Film 2. When you start Film 1, the contacts for Sensor Relays 1 and 3 will close. When you start Film 2, these contacts open and the contacts for Sensor Relays 2 and 4 will close.
Chapter 3 SQS-142 Software Max Power Relay Closes when any control voltage output is at the programmed maximum power level. Thickness Setpoint Relay This relay will become active when the Thickness Setpoint is reached. This is a programmable process parameter. Time Setpoint Relay This relay will become active when the Time Setpoint has been reached. This is measured from the beginning of the deposit phase, and is a programmable parameter.
Chapter 3 SQS-142 Software PLC Tab Model: Two models of PLC are supported. Select the model you are using. Comm Port: Selects the serial port used to communicate with the PLC. The Comm Port drop down lists available ports. However, some of the ports may be used by other devices (modem, mouse, etc.). Select Disabled to prevent I/O from using the PLC. Address: Several PLCs can be controlled from a single computer Comm Port by connecting their expansion ports.
Chapter 3 SQS-142 Software SQM-142 Tab Comm Port: Selects the serial port used to communicate with the PLC. The Comm Port drop down lists available ports. However, some of the ports may be used by other devices (modem, mouse, etc.). Select Disabled to prevent I/O from using the PLC. Period: Sets the measurement period between .2 seconds (5 readings per second) and 2 seconds. A longer period gives higher reading accuracy, especially at low rates.
Chapter 3 SQS-142 Software RS232 Tab Comm Port: Selects the comm port used for serial communications. The Comm Port drop down lists available ports. However, some of the ports may be used by other devices (PLC, modem, mouse, etc.). Baud Rate: Sets the comm port baud rate used for serial communications. Receive Data: Displays the Query and Update requests received from the serial port. See Appendix B for a description of the serial communications protocol.
Chapter 3 SQS-142 Software 3.4.5 Edit: Security The Security menu assigns Users, their Password, and their Access Level. It also provides a flexible way to assign program functions to different Access Levels. Note: The Security dialog is available only to users with Supervisor Access. Users Tab User: Drop down used to select an existing user for editing their Access or Password. It is not possible to edit or add a user name in the User drop down. Use the New SoftKey to create a new User.
Chapter 3 SQS-142 Software Access Tab The Access tab allows Supervisors to assign which main menu selections are available to each of the three Access Levels. When a program function is assigned to a particular access level, it is automatically available to higher access levels. In the example below, every user has access to the File Process menu and the File Exit menu. Only Supervisors have access to the Edit System and Edit Security menus. The remaining menus are assigned TECH access.
Chapter 3 SQS-142 Software 3.5 View Menu The view menu controls the appearance of the main display. Film Settings: Displays/hides a ribbon of process settings along the right of the screen. In codeposition, click on the desired film to display its parameters. When displayed, the settings ribbon allows the user to easily modify common process settings during deposition without leaving the main screen. Changes are made to the current process operation and the process database immediately.
Chapter 3 SQS-142 Software 3.6 Software Specifications Display Graphs .............................................................................Rate, Deviation, Power Readouts..........................................................................Rate,Dev,Thick,Power Process Parameters Name ...............................................................................12 characters # Processes .....................................................................Unlimited # Layers.....................
Chapter 3 SQS-142 Software Material Parameters Name ...............................................................................12 characters Density..............................................................................0.40 to 99.99 gm/cm3 Z-Factor ...........................................................................0.100 to 9.900 Computer Interface Type ................................................................................RS-232 Protocol ........................................
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Chapter 4 SQM-142 Card 4.0 Introduction This section covers installation, operation, and programming of the SQM-142 card. The SQM-142 is a deposition controller on a PC card. Each SQM-142 card has four 110MHz quartz sensor inputs, and two 0-10V control outputs. Up to two cards can be installed in a computer. The diagram below shows a typical single-sensor deposition system. The SQM-142 receives sensor inputs via a BNC cable from each sensor oscillator.
Chapter 4 SQM-142 Card 4.1 Installation The deposition control software uses a hardware interrupt (IRQ) to communicate with the SQM-142 card. Before installation, your computer BIOS and Windows operating system must be configured to accept the SQM-142 card, Identify an Unused Interrupt WIN 9X/ME: Open Control Panel, System, Device Manager, Properties. WIN NT: Open Administrative Tools, NT Diagnostics , Resources WIN 2000: Open Accessories, System Tools , System Info, Hdwe Resources Find an unused IRQ.
Chapter 4 Reserve IRQ in Windows SQM-142 Card WIN 9X/ME: Open Control Panel, System, Device Manager, Properties. Select Reserve Resources and reserve the IRQ selected on JP2 of the SQM-142. WIN NT/2000: An NT Patch program is included on CD-ROM with the SQM-142 card. Follow these three steps for NT/2000 systems: 1. Run the SETUPNT.EXE program. 2 If IRQ 10 is NOT the selected interrupt, edit the \windows\sqm32swnt.inf file (a standard text file) to the proper interrupt. 3. Execute the \windows\sqm32swnt.
Chapter 4 SQM-142 Card 4.3 Power Supply Connection The connection to your evaporation power supply is done through a 1/4” Stereo Phone Jack on the SQM-142 card. There are 2 control voltages on this connector, as shown in the figure below. The ground is common to both channels. Power supply input connectors vary. Consult your power supply manual. Ground Chan 1 (Ring) (Sleeve) Chan 2 (Tip) 4.
Chapter 4 SQM-142 Card 4.6 SQM-142 Specifications Sensor Inputs ...................................................................4 (BNC) Input Frequency................................................................1 to 10 MHz Input Type ........................................................................Active Oscillator Sample Period ...................................................................1 to 2 sec. Thickness Resolution* ........................................................2Å @ .
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Chapter 5 Digital IO 5.0 Introduction Digital I/O for the SQS-142 software is handled by an inexpensive Omron CPM1/CPM2 PLC. It is not necessary, however, to use external I/O with the SQS-142 software. There are several benefits to using an inexpensive external PLC for I/O. First, noisy high voltage wiring can be placed near the control sources, rather than routed into the controller’s equipment rack. Only a single serial cable runs from the PLC to the controller.
Chapter 5 Digital IO 5.1 PLC Installation Mount the PLC controller near the devices it is controlling and sensing. Connect the PLC to a properly grounded power source. Connect a serial cable from the PLC serial port to a computer serial port. See the PLC User Manual for detailed mounting and connection information. Output Wiring: The 10CH relays on Omron PLCs correspond to Relay# 1 to 8 in the SQS-142 software. These physical relays are mapped to relay events in the SQS-142 System Setup dialog.
Chapter 5 Digital IO Indexer Wiring: The SQS-142 software supports up to four source indexers (of up to 15 pockets) and a 15 position substrate indexer. However, each indexer is unique. Contact Sigma Instruments for information on the PLC program and I/O wiring required for your indexer. 5.2 PLC Setup and Test In the SQS-142 software select Edit, Setup, then the PLC tab. Set the Address to match the PLC Address. Set the Comm Port to the serial port you are using.
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Chapter 6 Computer Interface 6.0 Introduction The computer interface capabilities of the SQS-142 program allow operation from an external computer via RS-232 serial communications. The active process can be selected, process parameters read or changed, operation controlled, and data collected. Parameters may be read (Query commands) while the process is running, but can only be changed (Update commands) while the process is stopped. Changes to the “structure” of a process (e.g.
Chapter 6 Computer Interface 6.3 Protocol The SQS-142 program never initiates communications. It only responds to commands from the host computer. SQS-142 computer Interface commands fall into two general categories. Query commands request data from the SQS-142 program. Update commands instruct the SQS-142 program to take an action. The SQS-142 responds to both Query and Update commands with a response that indicates the results of the command request.
Chapter 6 Computer Interface Update Command: @;;...
Chapter 6 Computer Interface 6.3 Command Summary Note: Update Queries (except UP02-UP10) are only valid in Stop Mode Query Process: @QP; @QP;O6;Response @QP;21;ErrNum (Query) (ACK Response) (NAK Response) 01 Process Name @QP;01 (Query Process) @QP;06;MyProc (Process is MyProc) 02 Process Time @QP;02 (Query Process Time) @QP;06;32:45 (Time is 32 min., 45 sec.
Chapter 6 Computer Interface @UP;06; 02 Start Process @UP;02 @UP;06 03 04 05 06 07 08 09 10 2n Stop Process Start Layer Stop Layer Start Next layer Auto Mode Manual Mode Zero Thickness Force Final Thickness Output n Power (Manual Mode Only) @UP;21;50 (Set Output 1 to 50%) Query/Update Layer: 01 Film Name 02 03 04 05 06 07 08 1n 2n 3n @QL;;;
Chapter 6 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 3n Computer Interface Sample Time Sample Hold Ramp 1 Power Ramp 1 Time Soak 1 Time Ramp 2 Power Ramp 2 Time Soak 2 Time Feed Power Feed Ramp Time Feed Time Idle Power Idle Ramp Time Output (1-4) Source Index Max Power Slew Rate Material Tooling n (n=1 to 8) Query Measurement: @QM; 1n Output n Power (n=1 to 4) 2n Output n Rate 3n Output n Thickness 4n Output n Deviation 5n Sensor n Rate (n=1 to 8) 6n Sensor n Thickness 7n Sensor n Fre
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Appendix A.
Appendix Z-Factor is used to match the acoustic properties of the material being deposited to the acoustic properties of the base quartz material of the sensor crystal. Z-Factor is the ratio of the acoustic impedance of the sensor to that of the deposited material. If you know the acoustic impedance of your material, it is easy to calculate the Z-Factor. The sensor is basically silicon dioxide, and has an acoustic impedance of 8.83. For example, Gold has an acoustic impedance of 23.18, so: Gold ZFactor = 8.
