Custom layout basics course syllabus (Duration: 2.5 months)
- Requirements
- Design specification & architecture
- RTL Coding
- RTL integration
- Functional verification
- Synthesis
- DFT
- Physical Design
- STA
- Custom Layout
- Physical Verification
- Post Silicon Validation
- Combinational logic
- Number systems
- Radix conversions
- K-maps, min-terms, max terms
- Logic gates
- Realization of logic gates using mux’s and universal gates
- Compliments (1/2/9/10’s complement)
- Arithmetic operations using compliments
- Boolean expression minimization, Dmorgan theorems
- POS and SOP
- Conversion and realization
- Adders
- Subtractor
- Half subtractor
- Full subtractor
- Multiplexers
- Realizing bigger Mux’s using smaller Mux’s
- Implementing Adders and subtractors using Multiplexers
- Decoders and Encoders
- Implementing Decoders and Encoders using Mux and Demux
- Bigger Decoder/Encoder using smaller Decoder/Encoder
- Comparators
- Implementing multi bit Comparators using 1-bit Comparator
- Sequential logic
- Latch, Flipflop
- Latch, Flipflop using Gates or Mux’s
- Different types of FFs
- FF Truth table
- Excitation tables
- Realization of FF’s using other FF’s
- Applications of FF’s, Latches
- Counters
- Shift registers
- Synchronizers for clock domain crossing
- FSM’s
- Mealy, Moore FSM
- Different encoding styles
- Frequency dividers
- Frequency multiplication
- STA
- Setup time, Hold time, timing closure
- fixing setup time and hold time violations
- Launch flop, capture flop
- Linux/UNIX OS, Shell
- Working with files, directories
- Commonly used commands
- Basic Passive and Active devices.
- Ohms law, Kirchoff laws
- Basic of circuit understanding
- Transistors in hardware design
- Significance of transistors in hardware design
- Logic gate implementation using BJT, CMOS
- MOSFET functionality
- Semiconductors
- What makes Semiconductor special element?
- Classification of solids into three types
- Conductor, Insulator, Semiconductor
- Energy bands in Solids
- Types of Semiconductors
- Intrinsic Semiconductors
- Extrinsic Semiconductors
- Types of Extrinsic Semiconductors
- N-type Extrinsic Semiconductor
- P-type Extrinsic Semiconductor
- Si, Ge – comparison
- Types of current in Semiconductors – Drift, Diffusion
- ion
- PN Junction dioda
- PN Junction – forward, reverse bias
- V-I Characteristics of PN Junction Diode
- Different types of Diode
- Applications of Diode
- BJT
- BJT
- BJT working principle?
- How BJT can be used for large scale manufacturing
- BJT fabrication steps
- Types of BJT?
- Why BJT is not used in for lower technology nodes?
- Issues with BJT?
- Advantages of BJT?
- NAND gate using BJT?
- Field Effect Transistor : FET
- What is Field Effect Transistor?
- Types of FET
- NMOS
- PMOS
- CMOS
- Fin
- NMOS
- NMOS
- What is NMOS?
- NMOS working principle?
- Different voltages, currents, their equations
- NMOS circuit representation
- How NMOS works like a switch
- How NMOS can be used for large scale manufacturing
- NMOS fabrication steps
- Types of NMOS?
- Why CMOS is used instead of NMOS?
- Issues with NMOS?
- Advantages of NMOS?
- NAND gate using NMOS?
- CMOS
- CMOS
- What is CMOS?
- CMOS working principle?
- Different voltages, currents, their equations
- CMOS circuit representation
- How CMOS works like a switch
- How CMOS can be used for large scale manufacturing
- CMOS fabrication steps
- Types of CMOS?
- Issues with CMOS?
- Advantages of CMOS?
- NAND gate using CMOS?
- CMOS second order effects?
- FinFET
- FinFET
- What is FinFET?
- FinFET working principle?
- Different voltages, currents, their equations
- CMOS circuit representation
- How CMOS works like a switch
- How FinFET can be used for large scale manufacturing
- FinFET fabrication steps
- Types of FinFET?
- Issues with FinFET?
- Advantages of FinFET?
- NAND gate using FinFET?
- Layers of CMOS
- Depositing oxide layer
- Photholithography
- Masking
- Ethching Layers
- Formation of nwell
- Self aligned gate fabrication process
- Diffusion to create n+ and P+ regions
- Metallization
- Overview
- Env Setup
- Special Variables
- Data Types
- Variables
- Operators
- Decisions
- Loops
- Arrays, Strings, Lists, Dictionary
- History and Redoing of commands
- String Pattern Matching commands
Custom layout advanced course((Duration: 4 months)
- Layout Editor Tool
- Understanding the schematic symbols and parameters
- Creating and managing libraries and cell
- Commands for Layout editing.
- Commands for schematic editing.
- Verification : DRC and LVS
- Antenna effect, latchup, Electromigration, IR Drop
- Analog Layout of OpAmp, Current Mirror, PLL, ADC, and DAC
- Resistor, Capacitor layout techniques
- CMOS and BiCMOS layout techniques
- Standard Cell Layout : Inverter, AND, OR, NAND, NOR, AOI, OAI, Latches, and Flop
- Mismatches & Matching.
-
Failure Mechanism : Electro migration, IR drop, LOD & Stress effects, WPE, Antenna Effects, Latch up, ESD
(with High voltage rules, EOS effects).
- Noises & Coupling.
-
Different Types of process – Advantages & Disadvantages – Planar CMOS, FD-SOI, SOI, Bi-CMOS,
Gallium Arsenide, Silicon-Germanium, Finfet.
- Full Chip Construction, Scribe Seal, Pad Frame, Integration and guidelines.
- Packaging.
- Std Cell & Memories.
- IO Layout Guidelines : High speed IOs and High Speed Interfaces.
- Sense amplifier & Bit cell development
- Why memory layout different than analog layout
- Memory layout flow
- Types of memory layout (SRAM/DRAM/ROM)
- Introduction to SRAM memory layout
- Fixing few manually created leaf-cell errors which impact
- Abutment issues
- Impact of IR, EM and DFM .
- SRAM memory design architecture
- Words line and address line
- SRAM rows and column design
- Building blocks of SRAM
- Memory Bit cell
- Row decoder
- Word line driver
- Sense amplifier
- Control block
- Misc digital logic.
- Pitch Calculation for blocks.
- Power Planning
- High speed Analog Layout
- RF Layout guidelines with Transmission lines and inductor concepts
- Handling clocks
- Analog Circuits & Layout guidelines
- Single & Multi stage differential opamp layout
- current mirror layout
- PLL, DLL and Oscillators
- LDO and other regulators
- ADCs & DACs
- Bandgap, Temperature sensors & Biases -> Current & Voltage bias lines
- Large drivers
- input pair, differential routing, Power routing, offset minimising
- Power/Signal IR Drop
- cross-talk and coupling
- Electrostatic Discharge
- Deep Sub-micron Layout Issues
- Shallow Trench Isolation (LOD)
- Well Proximity Effect
- Design Rule Checks
- Layout Versus Schematic (LVS)
- Electrical Rule Checks (ERC)
- Antenna Checks
- Latch-up
- Reliability checks like EM and IR analysis
- Design for manufacturability (DFM)checks
- Electrostatic discharge (ESD) path checks
- Assignments and multiple hands on projects
- Best Practices & Interview Questions.
Course Overview
Custom layout training is a 6 months course focused on all the aspects of layout including Analog layout, Memory layout, Standard cell layout and IO layout. Custom layout design course ensures that the student is prepared on all the essential aspects of Custom layout including VLSI Design flow, advanced digital design, CMOS, FinFET, various memory architectures, Standard cell, IO’s and detailed analog layout techniques. Course also includes training on Linux commands, version control, scripting and soft skill for effective interview performance.
Course also includes detailed sessions on semiconductors, Ohms law, Kirchoff law’s, Diode-operation, MOSFET’s, MOSEFT operations, second order effects, FinFET’s, and detailed fabrication process, which is followed by assignments and hands on projects.
Course also covers layout basics, hands on standard cell layouts, IO layout and memory layout for different architectures. Followed by various analog layout techniques with detailed discussion on Mismatches & Matching, Noises & Coupling, various failure mechanisms which includes Electro migration, IR drop, LOD & Stress effects, WPE, Antenna Effects, Latch up, ESD. Course includes 20+ detailed labs & assignments covering all aspects of custom layout with multiple hands on projects.
Analog layout techniques involve multiple hands on projects covering various concepts such as common centroid, inter digitation, resistor matching, capacitor matching and opamp circuits, current mirrors, PLL’s, ADC’s, DAC’s, Bandgap, Temperature sensors & Biases -> Current & Voltage bias lines, Large drivers, LNA & Mixers, and Sense amplifier & Bit cell development.
Projects are the most significant part of any engineers(both fresher and experienced) resume. It is the projects that differentiate your resume from other resumes, which essentially helps your chances of getting through the interviews.
Below is the list of projects student will be doing as part of six months training. Student will be doing all these projects from scratch. These projects will provide student with expertise on par with a 2 to 3 years experienced engineer, in terms of all the skill set required. Student can work on additional projects to enhance resume for experienced job role.
By working on below projects, student will get familiar with:
- Complete layout flow including
- Floor planning
- Schematic
- Layout
- Physical verification
Description : Schematic, Layout design and verification for standard cell for NOT, NAND, NOR, AND, OR gate and
Buffer.
Role : Layout Design and Layout Verification.
Challenges : Involved in placement, routing by taking care of minimum area and Verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Designed the Layout for Level Shifter.
Role : Layout Design and Layout Verification.
Challenges : Involved in placement, routing by taking care of minimum area and Verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Designed the Layout for Schmitt Trigger.
Role : Layout Design and Layout Verification.
Challenges : Involved in placement, routing by taking care of minimum area and Verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Single stage Op-Amp designed, one with NMOS differential pair and the other with PMOS differential pair whose input and output are Shielded. Common Centroid matching technique was used while implementing differential input pair. Taken care of Electro migration to manage current in the last stage which is a high gain stage and proper care was taken to avoid latch up.
Role : Layout Design for OpAmp and Layout verification.
Challenges : Involved in placement, matching of MOS devices, routing by taking care of Electro migration and Layout verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Designed layout for the 4-bit Flash Analog to Digital converter. Main Challenge was matching of the resistors as any variation in the Resistance would results in the improper output.
Role : Layout Design for Block and Top level.
Challenges : Floor-planning considering different devices and precise resistors Matching and their Internal routing constraints. Routing by taking Care of resistance, IR and Top-level layout verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Designed the layout for 4 bit Digital to Analog converter. Main Challenge was the matching of the resistors.
Role : Layout Design for block level. Adjusted M1 and M2 pattern errors by adding fill cells and metal fills cleaned DRC, LVS
by using the CPDS.
Challenges : Floor-planning considering resistor. Routing is one by taking care of IR, symmetry and top-level layout
verification.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node : 28nm
Description : Designed the BGR with startup circuit. Main challenge was the matching of the resistors and symmetric routing.
Role : Layout Design for block level (BGR).
Challenges : Floor-planning considering different devices and BJTs and their internal routing constraints. Routing by taking care of Electro-migration, Latch-up and IR and top-level layout verification LVS/DRC.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node: 28nm
Description : Designed the Layout for LDO using single stage Op-Amp as error amplifier with large PMOS and feedback resistors. In which matching, area, Electro migration and shielding constraints are taken into consideration. Proper care was taken about Electro migration to manage high current in the last stage which is a high current stage.
Role : Layout Design for block level and top level.
Challenges : Floor-planning considering different blocks and their internal routing constraints. Routing by taking care of electro migration, shielding symmetry, IR and top-level layout verification LVS/DRC.
Tools Used : Synopsys Custom Designer & IC Validator (for DRC/LVS).
Technology Node : 28nm
Technology Node : 28nm
Role : layout of VCO, Charge pump, phase detector Cleaned DRC, LVS of the above blocks
Challenges : Sharing of devices, area minimization and routing issues. Also, matching must be there in layout by proper techniques.
Technology Node : 28nm
Role : Adjusted M1 and M2 pattern errors by adding fill cells and metal fills cleaned DRC, LVS.
Challenges : M1 layer is inbuilt present in Active devices, so M1 errors has to be cleaned without disturbing a floor plan. Also, need to clean the errors regarding higher metals