Wednesday, February 19, 2020

SEMI Standards For Equipment E30 GEM, E5 SECS-II, E37 HSMS, E4 SECS-I

Standards can be defined as any voluntary technical agreements between customers and suppliers created with the objective of improving product quality and reliability at an affordable price and steady supply. Standards make sure that interoperability & compatibility of goods and services are maintained.
SEMI standards are written in the form of guidelines, specifications, practices, test methods, terminology, etc. The documents which are published in the 16 volume set of SEMI International Standards. SEMI standards cover each and every aspect of semiconductor manufacturing and photovoltaic: Equipment Automation (Hardware and Software),3D-IC, High Brightness-LED, Facilities, Gases, Microlithography, MEMS/NEMS, Materials, Process Chemicals, Packaging, Photovoltaic, Traceability, Silicon Material & Process Control, and other related issues. Additionally, standards are published for Flat Panel Displays.

GEM defines a standard for implementing all semiconductor manufacturing
Equipment of SECS-II standard.
This standard SEMI E30 defines a common set of communication capabilities and equipment behavior that will provide the flexibility & functionality to support the manufacturing of automation programs for semiconductor device manufacturers. Any additional SECS-II features which are not included in GEM can be included by Equipment Suppliers, the only requirement is this feature should not conflict with GEM standards.
Any such additional features which may be included could be SECS-II messages, codes, variable data items (data values, status values or equipment constants)alarms, collection events, remote command, processing states, or other functionality which is unique to a class (etchers, steppers, etc.) or specific instance of equipment.
The main aim of GEM is to provide economic benefits for both equipment suppliers and device manufacturers. Equipment suppliers benefit from the feature to develop and market a single SECS-II interface that satisfies most customers. Device manufacturers benefit from the increased standardization and functionality of the SECS-II interface across all manufacturing equipment. This standardization reduces the cost of software development for both equipment suppliers and device manufacturers. By reducing costs and increasing functionality, device manufacturers can automate semiconductor factories more quickly and effectively. The flexibility provided by the GEM Standard also enables device manufacturers to implement unique automation solutions within a common industry framework.
The GEM Standard shows the following for Semiconductor Manufacturing Industry:
• The behavioral model to be exhibited by semiconductor manufacturing equipment in a SECS-II communication environment.
• Detailed information on the control functions required in a Semiconductor Manufacturing.
• Definition of the basic SECS-II communication capabilities of semiconductor manufacturing equipment.
• A single consistent way of achieving an action when SECS-II provides multiple ways for the same methods.
• It also shows the Standard message dialogues required to achieve useful communications capabilities.
GEM Standard contains two types of requirements. One is the Fundamental GEM requirements and the other is the requirements of additional GEM capabilities.
The foundation of GEM standards is laid by the fundamental GEM requirements. The additional GEM capabilities offer the functionality required for a few types of factory automation or functionality applicable to specific types of equipment.
Equipment suppliers and the customers should work hand in hand in order to ascertain which additional GEM capabilities should be incorporated for a specific type of equipment. Because the Capabilities defined in the GEM Standard are specifically developed to meet the factory automation requirements of semiconductor manufacturers, it is anticipated that most device manufacturers will require most of the GEM capabilities that apply to a particular type of equipment. Some device manufacturers may not require all the GEM capabilities due to differences in their factory automation strategies.
The scope of the GEM Standard is limited to defining the behavior of semiconductor equipment as viewed through a communications link. The SEMI E5 (SECS-II) Standard provides the definition of messages and related data items exchanged between host and equipment. The GEM Standard defines which SECS-II messages should be used, in what situations, and what the resulting activity should be.
The detailed interpretation of messages exchanged between SMART equipment and a host is defined in the SEMI Equipment Communications Standard (SECS-II).
This Standard is meant to be compatible with SEMI E4, Equipment Communication Standard(SECS-I) and alternative message transfer protocol.
This Standard defines messages at a very detailed level such that some host software can be developed with very little information on equipment as well as the equipment can be developed with very little knowledge of the host.
Most of the activities required for IC production are supported by the messages defined in the standards. These standards also outline the equipment-specific messages to support activities that are not considered by the standard messages. While some of the specific activities can be handled by common software in the host, it is expected that equipment-specific host software may be required to support the full capabilities of the equipment.
SECS-II defines the complete structure (form and meaning of the messages) of the messages exchanged between equipment and host with the help of a message transfer protocol, like SECS-I.
SECS-II defines the process of transferring the information between equipment and host in the form of messages. These messages are organized as per activities, called streams, which contain specific messages, called functions. A request for information and its corresponding data transmission is a simple example of such an activity.
SECS-II defines the structure of messages into entities called a list of items and items. This structure allows a self-describing data format that guarantees proper interpretation of the message.
The exchange of messages is governed by a set of rules for handling messages called the transaction protocol. The transaction protocol places some minimum requirements on any SECS-II implementation.
This Standard gives a means to independent manufacturers to produce equipment and/or hosts that can be connected without requiring specific knowledge of each other.
The SECS-I Standard lays a communication interface that is suitable for the exchange of messages between semiconductor processing equipment and a host. Semiconductor processing equipment includes equipment required 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 detail information about 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 is determined through a message content standard such as SEMI E5, Specification for SEMI Equipment Communications Standard 2 Message Content (SECS-II).
High-Speed SECS Message Services (HSMS) provides a way to independent manufacturers for producing implementations that can be connected and interoperate without requiring specific knowledge of one another.
HSMS is also intended as an alternative to SEMI E13 (SECS Message Services) for applications where TCP/IP is preferred over OSI.
It is intended that HSMS be supplemented by subsidiary standards which further specify details of its use or impose restrictions on its use in particular application domains.
HSMS defines a communication interface suitable for the exchange of messages between computers in a semiconductor factory.
Listed below the Subordinate Standards for SEMI E37:
SEMI E37.1-0819 — Specification for High-Speed SECS Message Services Single Selected-Session Mode (HSMS-SS)
SEMI E37.2-95 (Withdrawn 1109) — High-Speed SECS Message Services General Session (HSMS-GS)

Wednesday, January 1, 2020

Electronic Design Automation (EDA)

Electronic Design Automation (EDA) is an Industry that makes tools which helps in specification, design, verification, implementation and test of electronic systems.
Electronic design automation (EDA) is a category of software products/processes that help us to design electronic systems with the aid of computers. These tools are used to design processors circuit boards and various other types of complex electronics.
Electronic design automation is also known as electronic computer-aided design. Initially technicians used tools like photo plotter creating drawings of electronic components/Circuit Boards.
Earlier most of the tools were handcrafted. But things changed drastically in the year 1981 and there came the ERA of EDA.

Somewhere close to this period lot of big companies where internally following EDA structure. Buts it’s in the year 1981 that it was formalized by the industry and this became the industry Norm.
Many of the companies ventured into EDA business.
Significance of EDA for Electronics has continuously increased in the Semiconductor technology industry. Users who work in the Semiconductor fabrication facilities or fabs and design or service companies are the ones who use EDA software to analysis the design’s manufacturing readiness. FPGAs also use EDA tools for programming design functionality.
EDA has brought about a change in Electronics Components manufacturing, as the designs techniques are universal thus this elements errors and bugs in the design.
Digital flows available now days are extremely modular. The front end produces standardized design description that compile into invocations of “cells” disregards to the cell technology.
Logic or Electronic function is implemented by cells by using a particular Integrated Circuit(IC) Technology
Libraries of components are by and large provided by fabricators for their production processes along with simulation models that fit standard simulation tools.
Analog EDA tools are far less modular, since many more functions are required, they interact more strongly, and the components are (in general) less ideal.
As semiconductor technology is continuously scaling, Electronic Design Automation (EDA) has increased its importance enormously
Foundry operators are among those users, who operate the semiconductor fabrication facilities, or “fabs”, and design-service companies who use EDA software to evaluate an incoming design for manufacturing readiness and also EDA tools are used for programming design functionality into FPGAs.
Electronic Design Automation (EDA) has by and large impacted the industry by changing the way they thing:

Tuesday, October 1, 2019

Introduction to Multivariate SPC

A bunch of Advanced Techniques used for the monitoring and controlling of the operating performance of batch and continuous processes is known as Multivariate SPC (Multivariate Statistical Process Control Chart)

The most important benefit of Multivariate SPC techniques is it reduces the information contained within all the process variables down to two or three composite metrics by implementing statistical modeling technique. These composite metrics can be monitored easily in real-time in order to benchmark the efficiency of the process and determine potential problems, thereby providing a platform for continuous improvements in the operation process.

As the complexity of products and processes increases and the amount of data grows, traditional unilabiate SPC and analytical tools may not be competent enough to provide the insight required by the engineers for their routine activities. Instead, they will need to understand and control processes which are listed by multiple variables, where the relations between the variables are not only complex but also often unknown. The most challenging aspect of this is to make statistical analysis of multiple interdependent variables, more efficient, intuitive, understandable and reliable as unilabiate SPC and analytics.

MULTIVARIATE CONTROL CHARTS:

Multivariate Charts are control charts for variables data. Multivariate Statistical Process Control Charts are used to detect shifts in the relationship (covariance) between several related parameters.

Various different control charts for variables data are available for Multivariate Statistical Process Control analysis:

T2 control charts for variables data, based upon the Hoteling T2 statistic, are used for Analysing shifts in the process. In Place of using the raw Process Variables, the T2 statistic is calculated for The main Components of the process, which are linear combinations of the Process Variables. While the Process Variables may be correlated with one another, the Principal Components are defined in a way so that they are independent, of one another, as required for the analysis.

The Squared Prediction Error (SPE) chart can be used to detect shifts. The SPE is based on the error between the raw data and a fitted PCA (Principal Component Analysis) model (a prediction) to that data.

Contribution Charts are available to as a certain the contributions of the Process Variables to either the Principal Component (Score Contributions) or the SPE (Error Contributions) for a given sample. This is particularly useful for determining the Process Variable that is responsible for process shifts.

Loading Charts give an indication of the relative contribution of each Process Variable towards a given Principal Component for all groups in the analysis.

Few restrictions are an application to these Multivariate Statistical Process Control analyses:

• The process variables are restricted to a subgroup of size one.

• The provision for missing data is not available. If a sample row has an empty cell, this will throw an error message, requiring that either the affected variable/sample should be dropped from the analysis.

• This process specifically excludes PLS (Partial Least Squares) analyses, where the samples for the process variables are linked with quality parameters.

Multivariate SPCMultivariate Statistical Process Control ChartSquared Prediction Error

Computer Integrated Manufacturing (CIM)

IM – Computer Integrated Manufacturing is the approach in manufacturing for using computers to control the entire production process course.

The concept of CIM – Computer Integrated Manufacturing was conceptualized by Dr. Joseph Harrington in his book in the year 1974.

The CIM covers all the processes which are required to convert the customer requirements into output as per customers’ needs. According to U.S. National Research incorporating CIM into our process increases total productivity by 40-70 Percent.CIM decreases design cost by 15-20 Percent. It also reduces lead time by 20 – 60 percent and also cuts down work in progress by 30-60 Percent.

CIM process starts with product designing and ends with product sales.

CIM integration helps processes with information transfer with each other and initiate actions. Benefits of CIM are: Manufacturing can be faster and less error-prone as human intervention is minimal and computers take over the charge, the main advantage is the ability to create automated manufacturing processes. CIM relies mainly on closed-loop control processes, based on real-time input from sensors. This is also known as a flexible design and manufacturing process.

Computer-integrated manufacturing is implemented in the aviation, automotive, space and shipbuilding industries. The concept of “Computer Integrated Manufacturing” is not only a way of manufacturing but also a computer-automated system, where each engineering, production, marketing, and support functions of a manufacturing enterprise are planned efficiently.

In a CIM system, all the functional areas like designing, analysis, planning, purchasing, cost accounting, inventory control, and distribution are connected through the computer with factory floor functions such as materials handling and management, providing direct control and monitoring of all the operations.

As a method of manufacturing, three components distinguish CIM from other manufacturing methodologies:

The Components that distinguish CIM from other Manufacturing methodology’s are:

Means for data storage, Data retrieval, Data manipulation and the way it is presented
Mechanisms for sensing state and modifying processes.
Algorithms used for uniting the data processing component with the sensor/modification component.

CIM is a model of implementation of information and communication technologies (ICTs) in manufacturing. CIM implies that there are at least two computers involved in exchanging information, e.g. the micro-controller and the controller of an arm robot.

Parameters to be considered while incorporating CIM implementation in manufacturing are the production volume, the experience of the company or personnel to make the integration, the level of the integration into the product itself and the integration of the production processes.

CIM is useful where a high level of ICT is used in the facility, such as CAD/CAM systems, the availability of process planning and its data.

Monday, July 29, 2019

Smart Manufacturing in Semiconductor Manufacturing

Semiconductor Manufacturing covers various aspects of manufacturing, which includes wafer manufacturing, chip manufacturing, and product manufacturing.

Wafer Manufacturing includes building electronic circuitry layers on a Wafer.
Chip Manufacturing involves probing and testing.

Product Manufacturing involves the final IC assembling and final testing.

Semiconductor manufacturing is not only challenging but also very complicated production system that involves huge capital investment and advanced technology. Semiconductor product fabrication requires sophisticated control on quality, variability, yield, and reliability.

The most important process in Semiconductor Manufacturing is to automate all the processes. This Automation will make the process sequence and its respective parameter settings more accurate and effective and will also ensure that all the fabs various activities integration are more efficient & reliable.


Automation and integration are the two most important keys to success in modern semiconductor manufacturing.



Let’s talk about challenges in Automation and Integration in the Semiconductor Industry.

Automation has a very important role in the daily operations of semiconductor manufacturing.

Need for Automation in Semiconductor Manufacturing Industry aroused for the reasons which are common to most of the industries which opted for automation. And the reasons leading to automation were to make the process faster, more uniform output, replace humans in processes which could involve working in a hazardous environment

The ultimate goal of automation in semiconductor manufacturing is to eliminate human intervention in fab operations. Fab operations can be broadly classified as Manual, Semi-Automated and Fully Automated.

Manual Mode of operations also knows as a traditional model that does not use any computer assistance in fab tools is very scarce to find in today’s commercial fabs.


Semi-Automated operations still prevail in some 6- and 8-in fabs where processing tools are automated and controlled by computers, but the movement of materials to and from the tools is still handled by fab operators.

Automation in semiconductor manufacturing has to provide the complete state of the art to drive the operations of semiconductor fabrication processes, in which layers of materials are deposited on substrates, doped with impurities, and patterned using photolithography to generate integrated circuits(IC).

Automation in the semiconductor industry adopts the hierarchical machine control architecture that facilitates quick adaptability into current fabrication facilities. In this architecture, the lower level of the hierarchy includes embedded controllers to provide real-time control and analysis of fabrication equipment where sensors are installed for monitoring and characterization. At the higher-level, more complex, context- a dependent combination of processor metrology operations or materials movements are handled, sequenced, and executed.

Cluster tools are used by Contemporary semiconductor manufacturers. Each of these consists of several single-wafer processing chambers, for diverse semiconductor fabrication processes, shorter cycle time, faster process development, and a better yield with less contamination.

Semiconductor manufacturing integration involves- allocation, coordination, and mediation among system dynamics and flows of information, command, control, communication, and materials, in a timely and effective way. Due to the ever-increasing complexity of semiconductor devices and their manufacturing processes, Computer Integrated Systems (CIM) are essential for the smooth integration of semiconductor manufacturing. However, CIM systems generally are loosely coupled, monolithic, and difficult to support the ever-changing needs.

Due to various challenges in Semiconductor Manufacturing Integration, like the emergence of a new application, distributed systems, and data integrity, Researchers and Practitioners are working continuously towards building an integrated framework with common, modular and flexible mode to handle most critical issues in semiconductor manufacturing integration.