Browse Definitions :
Definition

stepper

Contributor(s): Matthew Haughn

A stepper is a machine used to project the image of a circuit in photolithographic semiconductor fabrication. 

The stepper conducts light exposure through a mask to project the circuit’s image, much like a negative image in standard photography. Here’s how it works: The stepper is loaded with silicon wafers with a photo-resistive coating. A robotic arm grabs a wafer and sets it on a wafer stage. The wafer is aligned, and then light (perhaps extreme ultraviolet) is cast through a quartz plate with a chrome pattern of the circuits that will be created.

This process hardens a photo-resistive layer on the printed circuit board (PCB) or silicon wafer. The hardened areas stay behind in the form of circuit paths of PCBs and CPUs.  Unexposed areas are then dissolved away by a solution bath, typically an acid in wet methods or plasma-like oxygen ions in dry methods.

See a simple demonstration of photolithography from the "Too Small to See" exhibition at the Cornell Nanotechnology Facility:

This was last updated in January 2014

Continue Reading About stepper

Start the conversation

Send me notifications when other members comment.

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • PCI DSS (Payment Card Industry Data Security Standard)

    The Payment Card Industry Data Security Standard (PCI DSS) is a widely accepted set of policies and procedures intended to ...

  • risk management

    Risk management is the process of identifying, assessing and controlling threats to an organization's capital and earnings.

  • compliance framework

    A compliance framework is a structured set of guidelines that details an organization's processes for maintaining accordance with...

SearchSecurity

  • Trojan horse (computing)

    In computing, a Trojan horse is a program downloaded and installed on a computer that appears harmless, but is, in fact, ...

  • identity theft

    Identity theft, also known as identity fraud, is a crime in which an imposter obtains key pieces of personally identifiable ...

  • DNS over HTTPS (DoH)

    DNS over HTTPS (DoH) is a relatively new protocol that encrypts domain name system traffic by passing DNS queries through a ...

SearchHealthIT

  • telemedicine (telehealth)

    Telemedicine is the remote delivery of healthcare services, such as health assessments or consultations, over the ...

  • Project Nightingale

    Project Nightingale is a controversial partnership between Google and Ascension, the second largest health system in the United ...

  • medical practice management (MPM) software

    Medical practice management (MPM) software is a collection of computerized services used by healthcare professionals and ...

SearchDisasterRecovery

SearchStorage

  • M.2 SSD

    An M.2 SSD is a solid-state drive (SSD) that conforms to a computer industry specification and is used in internally mounted ...

  • kilobyte (KB or Kbyte)

    A kilobyte (KB or Kbyte) is a unit of measurement for computer memory or data storage used by mathematics and computer science ...

  • virtual memory

    Virtual memory is a memory management capability of an operating system (OS) that uses hardware and software to allow a computer ...

Close