high level: we can relate all the process parameters to electrical characteristics
all the tests we can do
what they tell us, how many probes needed, etc.
example pictures, resulting curves
lots of great diagrams from Anirud, Icey, Ahmet, Joel working docs we can update with
Semiconductor Parameter Analyzer
Not all transistors are created equal. There is an immense amount of information within the electrical characteristics of the device that helps with optimizing the manufacturing process (Read Peter Van Zant Chapter 14). Below is an example of an ideal IV curve from a textbook, and the first IV curves taken in the Hacker Fab. While our curves aren’t perfect, they do exhibit transistor-like-characteristics 🙂.
IV curves are not the only tests that can be done with a parameter analyzer. With enough data, trends in these different curves can be directly associated with process parameters.
Probe stations are traditionally heavy desktop machines that hold probe manipulators. The purpose of the probe station itself is to precisely move the tungsten probe in order to make contact with the contacts of the device. This typically means moving 3 individual probes to the gate, source, and drain contacts, and another to contact bulk.
Probe Station + simple diagram of contact locations
These probes are attached to the back of the Semiconductor Parameter Analyzer - precision instruments consisting of multiple SMUs (Source Measure Units) and a built-in computer to control them and store readings. Source Measure Units are glorified power supplies with built-in voltmeters and ammeters - they are very precise instruments that are able to supply voltage or current through the probes, and simultaneously read voltage or current.
A guide on Analog Discoveries and Waveforms Software
A portable USB-powered test and measurement device, also known as the AD3, is a digital oscilloscope, logic analyzer, waveform generator, pattern generator, and much more. Digilent WaveForms software makes it easy to acquire, visualize, store, analyze, produce and reuse analog and digital signals.
Analog Discovery 3
$379
3
Jumper Cables set
$6.98
1
Micropositioners
TBD
4
Total Cost:
Setup Time:
Output Voltage Range: ±5 V
Accuracy:
±10 mV ± 0.5% (│Vout│ ≤ 1.25 V)
±25 mV ± 0.5% (│Vout│ > 1.25 V)
Number of channels: 2 (custom channels feature available)
DC Current Drive: 30 mA maximum
Download the Waveforms software: https://digilent.com/shop/software/digilent-waveforms/
Run the .exe installer
Plug the Analog Discovery 3s into the laptop and open up the Waveforms software.
Set up the circuit that connects the Analog Discovery 3 like this circuit diagram:
The actual circuit will look something like this:
For our purposes, click on Tracer (for IV Characterization).
Click on drop down to select transistor type.
Select “No Adapter”
Select “Measure Id/Vgs” and set the ranges for the Vgs and Vds.
Select step-size/no. of steps for both voltages.
Click play (in the top right corner) and watch the magic!
I-V Curve for ZVN3310A Transistor on Curve Tracer (replace this image with our chip curves).
Can adjust current compliance for Gate if needed. (below the main toolbar, right above the graph).
Get the code from github by typing in terminal
Cd into this directory then run the below Python script in any environment where Python is installed by typing in terminal
If this is the first time being run in this environment, make sure all dependencies are installed by typing the following command in terminal:
