SEMI E4 - Specification for SEMI Equipment Communications Standard 1 Message Transfer (SECS-I)

Volume(s): Equipment Automation Software
Language: English
Type: Single Standards Download (.pdf)

This Standard was technically approved by the Information & Control Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on December 13, 2017. Available at and in April 2018; originally published in 1980; previously published June 2012.


This Standard provides a means for independent manufacturers to produce equipment and/or hosts which can be connected without requiring specific knowledge of each other.


The SECS-I Standard defines a communication interface suitable for the exchange of messages between semiconductor processing equipment and a host. Semiconductor processing equipment includes equipment intended for wafer manufacturing, wafer processing, process measuring, assembly and packaging. A host is a computer or network of computers which exchange information with the equipment to accomplish manufacturing. This Standard includes the description of the physical connector, signal levels, data rate and logical protocols required to exchange messages between the host and equipment over a serial point-to-point data path. This Standard does not define the data contained within a message. The meaning of messages must be determined through some message content standard such as SEMI E5, Specification for SEMI Equipment Communications Standard 2 Message Content (SECS-II).


Referenced SEMI Standards

SEMI E5 — Specification for SEMI Equipment Communications Standard 2 Message Content (SECS-II)
SEMI E6 — Guide for Semiconductor Equipment Installation Documentation

Related Products
Interested in purchasing additional SEMI Standards?

Consider SEMIViews, an online portal with access to over 1000 Standards.

Refund Policy: Due to the nature of our products, SEMI has a no refund/no exchange policy. Please make sure that you have reviewed your order prior to finalizing your purchase. All sales are final.

Member Price: $113.00
Regular price Non-Member Price: $150.00