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pmos3_344 help

The ICCAP Instructions contain the basic procedures for making measurements and performing modeling. This screen is intended to point out things unique to using the pmos3_344.mdl model file.

The pmos3_344.mdl model will help you find the SPICE model for PMOSFETs on your wafer. Unlike the BJT model which finds the SPICE parameters for a particular BJT geomometry, this model will use 3 very different PMOSFETs to find a model which is a function of the "as drawn" geometry.

Device Selection

Below are some guidelines for chosing which devices to measure for each of the Devices Under Test (DUTs). Normally, you will only have to fill in a single model since each requires probing 3 devices.

large: Use the 20 micron gate oxide PMOSFET
narrow: Use one of the leftmost FETs in the bottom row of the PMOSFET array.
short: Use the shortest channel gate oxide PMOSFET you can find that works. Hopefully, this will be in the top row of the array.
cbd1: Use the "large" FET for this measurement. It doesn't really matter whether the Drain or Source is used for the CM(L) connection.
cbd2: Use the "narrow" FET for this measurement. It doesn't really matter whether the Drain or Source is used for the CM(L) connection.

Probe Assignments

SMU1/probe1/CM(H)---->Substrate
SMU2/probe2---->Drain
SMU3/probe3---->Gate
SMU4/probe4---->Source

Note: CM(L) will have to be connected to either the Drain(probe2) or Source(probe4) as needed to complete the measurements.

Variables and Parameters

Entries under the following locations should be made or verified before performing any extractions, simulations, or optimizations. Note that some of the parameters may change as part of optimization.

Parameter Set | Edit.
- TOX - Gate Oxide thickness: Enter the ellipsometer results in meters.
- XJ - Junction Depth: This can be either the predicted junction depth or the depth measured with the Junction Grinder.
- LD - Latteral Diffusion: Enter 1/2 of the delta L (as drawn channel length minus effective channel length) you calculate as part of the report. You will have to add some new plots for this.
- NSUB - Substrate doping: Determine this from the mosc_B_344 measurements.
Model | Edit Variables.
- AreaCap1,2 - Areas of the Drains of the large and narrow FETs, respectively. Use LASI to measure.
- PerimCap1,2 - Perimeters of the Drains of the large and narrow FETs, respectively. Use LASI to measure.
- Device_Cell_#
Edit for each DUT name.
- L - Channel Length. Use LASI to measure.
- W - Channel Width. Use LASI to measure. Leave in the "-2*WD" term. This allows IC-CAP to include the effects of WD.
- AD,S - Areas of the Drain and Source respectively. Use LASI to measure.
- PD,S - Perimeters of the Drain and Source respectively. Use LASI to measure.
Here is a set of measurements you can use for the entries above. It would still be good to use LASI to make the measurements yourself though.


   1st Row L(um)/W(um)	Peri-Left (um)	Peri-Right(um)	Area-L (um^2)	Area-R

	1/100		399		399		9950		9950
	1.5/100		398		399		9900		9950
	2/100		398		398		9900		9900
	2.5/100		398		397		9900		9850
	3/100		397		397		9850		9850

	2nd Row		

	4/100		396		396		9800		9800
	6/100		394		394		9700		9700
	8/100		392		392		9600		9600
	10/100		390		390		9500		9500
	20/100		380		380		9000		9000

	3rd Row  Field Oxide

	1.5/100 	398		399		9900		9950
	2/100		398		398		9900		9900
	4/100		396		396		9800		9800
	8/100		392		392		9600		9600
	10/100		390		390		9500		9500

	4th Row

	10/4		290		290		2680		2680
	10/8		290		290		2860		2860
	10/16		290		290		3220		3220
	10/32		290		290		3940		3940
	10/64		318		318		5380		5380

Related Models

linked_models/pmos3.mdl: Sample Plots can be found by loading linked_models/pmos3.mdl using MODEL | Read Model. This model was bundled with ICCAP and contains setups which require instruments we do not have in the lab (yet). The plots with the same names should show basically what you should expect your plots to look like (although the scales may be much different). I hope curiosity will get you to explore the components which have been stripped out of the ECE 344 version, however.
Before submitting your my_models.mdl file delete the "pmos3" model it added and resave.
mosc_B_344: Make these measurements on the round "B" capacitors. You can determine the doping level of the silicon from the capacitance measurements. Plug the result into the value for NSUB in the parameter set.

Manual Excerpts

The pmos3_344.mdl model file is based on a model file included with ICCAP. Excerpts from their manuals have been scanned in for viewing by uiuc.edu machines (or soon will be).

Save often!

ECE 344 home page.

This screen was created by Mike Fitzsimmons - U of Illinois ECE Dept. - mikef@uiuc.edu

E-mail comments and suggestions to ece344@uiuc.edu or use the FEEDBACK FORM.

I like to edit this file with the command:

vuepad /ece344/Software/ICCAP/pmos3_344.help.html &

Warning! This is the archived 1999 Fabweb site! Here is the latest site