Glossary

1X reticle
The reticle is the medium by which a stepper can transfer a chip design from an engineer's computerized layout to the wafer. Ultratech wafer steppers manufactured at the San Jose facility use a Wynne-Dyson lens design and 1X reticle technology.

Annealing
A baking process typically used to incorporate doping atoms into the silicon crystal lattice.

ASIC
Application-specific integrated circuit.

Aspect ratio
The width-to-height ratio of patterned features on a substrate.

Bump processing
A method of placing "bumps," typically solder or other conducting material, onto IC bond pads so that the IC is mounted to either a package or a printed circuit board directly.

Cost of ownership
The total cost a manufacturer incurs to "own" a piece of capital equipment throughout that equipment's lifetime, including initial costs and yearly operating costs.

Doping
The deliberate introduction of specific impurity atoms into the silicon crystal lattice to change its electrical properties.

DRAM
Dynamic random-access memory.

gh-line
Exposure wavelength of 436 nanometers.

GILA (Gas Immersion Laser Annealing)
A self-aligned silicide (SALICIDE) process for forming low resistance contacts at sub-critical dimension spacing as part of high-performance CMOS logic fabrication.

i-line
Exposure wavelength of 365 nanometers.

Inductive thin film head
An electromechanical device that records (writes) data on and retrieves (reads) data from the magnetic recording layer of the disk inside the disk drive. Inductive heads read and write data using a conductive coil wrapped around a very small stylus.

Magneto-resistive (MR) head
Recording head that uses an inductive thin film element to write data onto the media and a separate MR element to read the data. The use of a separate but much more sensitive read element permits data to be recorded and, subsequently, read at much higher track densities than inductive thin film head technology.

MEMS (Microelectromechanical systems)
A term often used interchangeably with micromachining.

Micromachining
The application of integrated circuit fabrication processes to the manufacture of miniature machines, sensors and switches.

Micron
One millionth of a meter.

Minimum feature size
The smallest dimensions imaged on the wafer's surface.

Mix-and-match
The cost-effective strategy by which manufacturers use expensive reduction steppers for the critical layers of an integrated circuit and cost-effective 1X steppers for layers larger than 0.65 microns.

MVS (Machine Vision System)
A pattern recognition alignment system that eliminates the need for large scribe lines to support dedicated alignment targets.

P-GILD
Projection-Gas Immersion Laser Doping. This process merges photolithography, doping and annealing.

Photolithography
Photography is the best analogy to describe the photolithography process. The stepper is like a photographic enlarger where a light source projects an image through a lens system onto photographic paper. The machine used to do all of this is called a "stepper" because it literally does one die or a few die at a time, then steps to the next die or set of die until it has exposed the entire wafer.

Photomask
Also known as a "reticle" or "mask," this glass plate contains the patterns used for photolithographic manufacture of integrated circuits.

Photoresist
A photoactive film also known as "resist." Liquid photoresist is applied to a wafer to create a thin, uniform film. This film reacts with light energy from the stepper to define a circuit or component pattern on the substrate.

Photosensitive polyimide
A stress buffer overcoat used in the manufacture of devices designated for advanced packaging applications. The photosensitive properties of the material enable manufacturers to achieve in only four steps what would otherwise require nine steps for nonphotosensitive polyimide.

Primary Lithography
A lithography market including the manufacture of low cost IC's, consumer products, micromachining devices and various semiconductor processes with minimum line-width requirements ³ 0.65 micron. This market also includes scanner replacement for capacity expansion, wafer size upgrades and new process integration.

Reduction stepper
Steppers that reduce the image contained on the reticle nX times, usually 5X, but sometimes 4X, 2.5X or 2X, before exposing the wafer.

Refractive lens
A lens (composed of glass lens components) that bends or deflects the path of light as it passes between different media, for example, air or gas.

Scanner
Scanners are lithography tools that were first introduced in the early 1970s to replace contact printers. Today, scanners are being replaced by higher-technology steppers.

Semiconductor
An electronic device (also referred to as an integrated circuit or IC), such as memory or a microcontroller, used in a variety of applications including computer, automotive and telecommunications products.

Stepper
A photolithography tool used in the production of semiconductor devices, thin film recording heads, micromachined devices and so forth. Also referred to as a step-and-repeat projection aligner, stepper works by transferring the image of a circuit or component from a master photomask image onto a small portion of the wafer surface. The substrate is then moved or stepped, and the image is exposed once again onto another area of the wafer. This process is repeated until the entire wafer surface is exposed.

Substrate
See wafer.

Thin film head
Currently, the most advanced type of magnetic recording head used to read and write information on disk drives. The two types of TFHs are inductive and the more advanced magneto-resistive.

Wafer
1. Semiconductor wafers are made of round, thin slices of single-crystal silicon and form the base substrate for semiconductor processing.

Wafer plane irradiance
Exposure light at the substrate surface.