EEE112 Integrated Electronics and Design - NMOS IC Design Project
EEE112 Integrated Electronics and Design NMOS IC Design Project
Assessment Weighting
This assessment counts for 20% of the module.
Aims
This project aims to provide students with an experience of designing a simple integrated circuit at the silicon layout level, as well as offering an insight into the manufacturing process flow.
Learning Outcomes
On completion of this project you should be able to:
- Understand the manufacturing processes involved in fabricating silicon - based devices.
- Understa nd the design process and constraints involved in developing IC.
- Produce layout and mask designs to scale of an NMOSFET logic circuit.
- Produce an engineering style report.
Design Task
The objective of this assignment is to design the simple logic cir cuit shown in Figure 1.
Fig. 1 Simple Logic Circuit
Task 1 : What is the logic function of simple logic circuit in Fig. 1?
Task 2 : What is the aspect ratio (W/L) for all the NMOSFET s in the circuit (total 4 NMOSFETs)? Please note that the V OUT is assum ed to be 0.2V, 0.1V and 0.01V respectively. Please calculate the aspect ratio (W/L) for all the NMOSFETs under different V OUT (0.2V, 0.1V and 0.01V).
The process parameters for the design are listed in Table 1.
Table 1: Process Parameters
Normalized Device Constant β0 1.8x10-4 A/V2 Threshold Voltage V T 0.5 V Supply Voltage V DD 5 V High Input Voltages (A and B) V IN V DD Low Input Voltages (A and B) V IN 0 V Sheet Resistance R S 100 Ω/□
Task 3 : 4-mask process is applied for the manu facturing of the NMOSFET. It is required to provide the process flow from step one till the last step. Each step shall have its top view and cross -section view. Please take NMOSFET A as an example (W/L ratio upon VOUT=0.1V ).
Task 4 (Extra ): If we use the TSMC 7nm technology, 2λ (feature si ze) is 7nm. Y ou are encouraged to produce a full circuit design layout (full layout) to scale together with the necessary masks to form each layer (from mask 1 to mask 4) , by considering the MOSIS design rules (see the last page ), and your kno wledge from t he lectures. (W/L ratio upon VOUT=0.1V )
You are highly appreciated minimize the full layout as compact and small as possible, following the MOSIS design rules .
Assignment Output and Grading Information
It is required to write a shor t formal report (no more than 35 pages in tot al). The report will be graded against the requirements are set out below:
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Report format : cover page, contents, abstract, introduction, main body, conclusion, references.
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Main body 1 (Task 1): What is the logic function of simple logic circuit in Fig . 1?
Detailed analysis should be given together with truth table of the simple logic circuit .
- Main body 2 (Task 2): What is the aspect ratio (W/L) for all the NMOSFETs in the circuit (total 4 NMOSFETs)? Please not e that the V OUT is assumed to be 0.2V, 0.1V and 0.01V respectively. Please calculate the aspect ratio (W/L) for all the NMOSFETs under different V OUT (0.2V, 0.1V and 0.01V).
The process parameters for the design are listed in Table 1.
Table 1: Process Pa rameters
Normalized Device Constant β0 1.8x10-4 A/V2 Threshold Voltage V T 0.5 V Supply Voltage V DD 5 V High Input Voltages (A and B) V IN V DD Low Input Voltages (A and B) V IN 0 V MOSFET Load Resistance R L 5 kΩ Sheet Resistance R S 100 Ω/□
Please provide the detailed analysis for the c alculation. It is also important to identify which mode (linear or saturation) for all the NMOSFETs in the circuit (total 4 NMOSFETs) .
- Main body 3 (Task 3): 4-mask process is applied for the manufacturing of the NMOSFET. It is required to provide the pro cess flow from step one till the last step. Each step shall have its top view and cross -section view. Please take NMOSFET A as an example (W/L ratio upon V OUT=0.1V ). 10% 20% 30% 40%
Clearer and detailed discussion for all the step s are required in this section, together its top view and cross -section view.
- Main body 4 (Extra ): If we use the TSMC 7nm technology, 2λ (feature size) is 7nm. You are encouraged to produce a full circuit design layout (full layout) to scale together wit h the necessary masks to form each layer (from mask 1 to mask 4), by consid ering the MOSIS design rules (see the last page), and your knowledge from the lectures (W/L ratio upon V OUT=0.1V ).
You are highly appreciated minimize the full layout as compact an d small as possible, following the MOSIS design rules.
You are suggested to use handwrite or software for the full layout and four masks. Full layout means the final layout merging four masks together. For handwrite, either photo or scan into the report i s acceptable . For software, figure capture is acceptable .
Please identify the related MOSIS design ru les in your design. (unit: nm)
Mask information is listed as follow:
- Mask 1 : Active layer
- Mask 2 : Poly -Si layer
- Mask 3 : Contact layer
- Mask 4 : Metal layer
- Full layout : Overlay of all the m asks (merging four masks together)
Academic Misco nduct
Students should be aware that when submitting assessed work that the work is their own and that it fully acknowledges the work and opinions of othe rs. For further clarification students should read the latest version of the XJTLU Code of Conduct. Th ese can be found on the university web pages.
Assignment Submission and Deadline
Please submit your completed des ign assignment report directly to the assignment on Learning Mall no later than:
6pm May 17 2023 Wednes day (Week 1 4)
Late submission shall f ollow university policy available on the university website.
Note: Please make sure you attach the university assignment cover sheet to your report . Extra 10%
MOSIS Layout Design Rules Active Area Rules R1 Minimum Active area Width 3λ R2 Minimum Active area Spacing 3λ Poly -Silicon Rules R3 Minimum Poly Width 2λ R4 Minimum Poly Spacing 2λ R5 Minimum Gate extension of Poly over Active 2λ R6 Minimum Poly -Active Edge Spacing λ (Poly Outside of Active area) R7 Minimum Poly -Active Edge Spacing 3λ (Poly Inside of Active area) Metal Rules R8 Minimum Metal Width 3λ R9 Minimum Metal Spacing 3λ Contact Rules R10 Poly Contact size 2λ R11 Minimum Poly Contact Spacing 2λ R12 Minimum Poly Contact to Poly Edge Spacing λ R13 Minimum Poly Contact to Metal Edge Spacing λ R14 Minimum Poly Contact to Active Edge Spacing 3λ R15 Active Contact size 2λ R16 Minimum Active Contact Spacing 2λ (On the same Active region) R17 Minimum Active Contact to Active Edge Sp acing λ R18 Minimum Active Contact to Metal Edge Spacing λ R19 Minimum Active Contact to Poly Edge Spacing 2λ R20 Minimum Active Contact Spacing 6λ (On different Active regions) Supply Rail Metal R21 VDD >3λ R22 Ground >3λ Resistor Rules R23 Minimum resistor width 2λ
