Course Grade Contribution of Quizzes

The best five out of six quizzes will contribute to the overall grade, each worth 3%.

Closed-book, closed-notes exam, allowing a one-page handwritten cheat sheet. Comprehensive coverage of the course material.

Four projects, each worth 8.75%, involve working in pairs. Grading is based on reports and/or presentations, focusing on design procedure, simulation results, challenges faced, and project specifications.

Closed-book, closed-notes exam, allowing a one-page handwritten cheat sheet.Comprehensive coverage of the course material.

This software is essential for the projects, alongside Matlab. Use these to design and simulate your CMOS circuits.

This software is used in conjunction with Cadence Virtuoso for projects. It aids in analysis and simulations.

These are usually ungraded, but they are designed to prepare you for the upcoming quizzes, so try your best!

This refers to the target specifications for the project design. You should strive for a minimal discrepancy between your simulation results and these specifications, aiming for less than a 10% deviation.

A type of integrated circuit (IC) where many transistors are packed onto a single chip. This allows for the creation of complex and powerful devices.

A very high level of integration in circuits, where millions or even billions of transistors are packed onto a single chip. This leads to extremely complex and powerful devices.

A type of transistor commonly used in VLSI circuits. They are known for their speed, low power consumption, and cost efficiency.

The process of creating a physical layout of transistors and other components on a chip. This involves designing the arrangement, size, connections, and placement of each element.

The process of manufacturing or creating integrated circuits (ICs) by transferring patterns onto silicon wafers using various techniques, including photolithography and etching.

A silicon crystal lattice is a regular arrangement of silicon atoms in a three-dimensional structure, where each silicon atom is bonded to four neighboring atoms. This arrangement forms the foundation for creating transistors and other semiconductor devices.

Group IV materials are elements found in the fourth column of the periodic table, characterized by having four valence electrons. Silicon, being a Group IV material, is vital for creating semiconductor devices due to its bonding properties.

A material that conducts electricity but not as well as a conductor and not as poorly as an insulator. Silicon is a semiconductor, making it ideal for creating transistors and integrated circuits.

A CMOS inverter is a basic logic gate that inverts the input signal. When the input (A) is 0, the output (Y) is 1, and vice-versa.

A CMOS NAND gate outputs a 1 only if BOTH inputs (A and B) are 0. Otherwise, the output is 0.

A CMOS NOR gate outputs a 1 only if BOTH inputs (A and B) are 0. If either input is 1, the output is 0.

A 3-input NAND gate outputs a 1 if any of the inputs (A, B, or C) is 0. However, if all inputs are 1, the output becomes 0.

CMOS transistors are manufactured on silicon wafers using a process like printing. Layers of different materials are deposited and etched to create the transistors.

CMOS fabrication requires a multi-step process where materials are deposited and etched on silicon wafers. This process is similar to printing with different layers being added on top of each other.

CMOS fabrication involves a complex process of layering and etching materials on a silicon wafer. Imagine it like building a chip piece by piece with different materials.

Silicon is a material that conducts electricity poorly in its pure form. It's like a traffic jam with no cars — not very efficient! To improve conductivity, we add 'dopants,' which are like special 'traffic controllers' that add or remove electrons.

Group V dopants have one extra electron, like a party with an extra guest, which can move freely and increase conductivity. This is called 'n-type' because it adds 'negative' charges.

Group III dopants have one missing electron, like a missing plate at a dinner party. This hole can attract electrons and contribute to conductivity. This is called 'p-type' because it creates a positive charge.

A p-n junction is a special connection between a p-type and an n-type semiconductor. This forms a diode, which acts like a one-way street for electricity.

An nMOS transistor consists of four parts: gate, source, drain, and body. It's like a special switch controlled by the gate, where the source and drain act like the on and off buttons, and the body provides the base for the switch.

The gate in an nMOS transistor, along with the oxide layer and the body, form a capacitor. Think of it as a storage tank for electrical energy.

When the gate voltage is low, the transistor is 'OFF.' It's like a closed switch, preventing any current from flowing from the source to the drain.

When the gate voltage is high, the transistor is 'ON,' like a switch that allows current to flow from the source to the drain. It's like turning on the light switch.

The process of removing the leftover photoresist after lithography. A mixture of acids called Piranha etch is used for this step.

A region in a p-type silicon substrate that is doped with n-type impurities (usually arsenic) creating a region with higher electron concentration.

A method of doping silicon with arsenic atoms by placing the wafer in a furnace with arsenic gas, allowing the arsenic atoms to diffuse into the exposed silicon.

A technique where a beam of arsenic ions is directed at the wafer. The ions penetrate the exposed silicon, changing its conductivity.

The final step in the n-well formation process where the remaining SiO2 layer is removed using hydrofluoric acid (HF), revealing the bare silicon wafer with the n-well.

A very thin layer of silicon dioxide (SiO2) deposited on the wafer surface. It acts as a gate insulator, preventing current flow between the gate and the channel.

A layer of polycrystalline silicon deposited on the gate oxide. It acts as the gate electrode, controlling the flow of current through the channel.

The process of patterning the polysilicon layer using the same lithography techniques as before. This defines the shape and size of the gate electrode.

The metalization process in CMOS fabrication involves first depositing a layer of aluminum over the entire wafer, then selectively removing the aluminum layer using a pattern to create the desired metal interconnections. This process connects various components on the chip, enabling current flow and circuit functionality.

The layout of a chip is defined by a set of masks, which determine the minimum dimensions of the components. These dimensions significantly impact the size, speed, and cost of a transistor. Feature size, the distance between source and drain, is primarily governed by the minimum width of the polysilicon layer. Technological advancements have been driving the reduction of feature size by an impressive 30% every 3 years, leading to ever-smaller transistors and denser chips.

The minimum size for a transistor is often referred to as '1 unit,' which in a 0.6 µm process corresponds to dimensions of 1.2 µm (width) and 0.6 µm (length). This minimum size dictates the physical limits of the transistors on a chip.

MOS transistors are made up of layers of gate, oxide, and silicon, and they act as electrically controlled switches. These fundamental switches are the building blocks of logic gates. The specific layout of transistors on a chip is determined through the fabrication process, which involves designing and creating masks that define the arrangement and dimensions of the transistors.

The design rules are a set of guidelines that govern the layout of transistors and other components on a chip. These rules ensure that the circuit functions correctly and prevents potential issues arising from the physical dimensions of the components. These rules are often expressed in terms of lambda, which is half the feature size, providing a convenient scale for defining the geometry of the circuit.

Inverter layout is the process of designing the physical arrangement of transistors to create an inverter, a fundamental logic gate. Transistors are typically specified by their width and length. When designing an inverter, the transistor dimensions are critical for determining the performance of the circuit.

Conservative design rules provide a safe starting point for designing circuits, ensuring that the basic functionalities are met while focusing on a reliable design. However, they may not always be the most optimized or efficient design in terms of area, performance, or power consumption.

Simplified design rules are a set of basic guidelines that are easier to understand and apply, particularly for beginners. They provide a simplified framework for understanding the concept of chip design without delving into the complexities of all the advanced fabrication processes.