The semiconductor industry's Semi standard GUI
07/01/2000
Shawn Jipp, Nanometrics, Sunnyvale, California
Frank Summers, Industrial-Strength Graphics Inc., Peterborough, New Hampshire
overview
The new Semi Standard E95-0200 specifies a unified user interface GUI for the semiconductor industry. A straightforward, intuitive screen layout displays information in an efficient and comfortable manner to enable operators to navigate critical function controls accurately and rapidly. Such an industry standard simplifies software development and equipment operation and reduces production errors in the fab.
The semiconductor equipment industry is known for its diverse computer control equipment, user interfaces, and operating systems. Sometimes it seems as if the equipment manufacturers are trying to outdo each other. Every time a new tool is added to the fab floor, the engineer who ordered the system must learn to control it and use all its features. He or she must then train other engineers and system instructors. Finally, the operators must cope with the wide assortment of computer systems that are thrown at them. It can truly be daunting.
 Figure 1. The standard screen layout of Semi E95-0200 is divided into four panels. |
It was inevitable amid all this confusion that a demand would arise for a unified graphical user interface (GUI) in the fab. The new standard — Semi E95-0200: Specification for Human Interface for Semiconductor Manufacturing Equipment — addresses this problem and is a result of more than three years of combined effort in the semiconductor industry to define what a new and logical GUI should look like (see "History of Semi E95-0200" on p. 264).
Teams in both the US and Japan worked on the specifications to make sure that it would work well globally. The new Semi standard is a logical and natural evolution in human-computer-interface (HCI) design. It reduces the software development cycle for the equipment manufacturer while increasing ease of use and reducing production errors in the fab.
Adopting E95 will help simplify manufacturers' interfaces and provide a commonality among all processing equipment in the fab of the future, leading to shorter learning curves, better comprehension of new tools, lower training costs, and better utilization of semiconductor manufacturing equipment.
Benefits of Semi E95-0200
 Figure 3. Relationship of navigation buttons to information panel displays in the E95 model. Each button opens a tab view on the information panel. |
Over the last five years, all the features and requirements of E95 have been successfully implemented on PVD, CVD, and etch cluster tools, ion implanters, chemical mechanical planarization (CMP) systems, and now, metrology equipment. In an informal survey conducted by Industrial-Strength Graphics Inc., manufacturers realized the following benefits:
- Rapid development — there is a 50% reduction in initial design time.
- Rapid implementation — software re-use saves money and time on a second GUI.
- Rapid training — 25% less class time is spent on GUI operations instruction.
- Rapid sales — buyers demand a new GUI on OEM's other product.
- Rapid processing — misprocessing drops by 35%.
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These responses were from companies that were willing to quantify their results. Other responses were favorable, and some added observations about the effort required to maintain the user and task orientation that is the backbone of the standard. This proved to be an area that needed fairly constant reinforcement within their development groups, as previous GUIs focused on exposing software or hardware functionality to the user rather than presenting information to ensure ease of use and efficient wafer production. All the companies commented in one way or another that their customers were very pleased with their new GUI, and they felt it was a significant step forward.
The new GUI look
 Figure 4. Partial view of the Nanometrics N2000 automatic-processing window, where an operator can start one recipe while queuing another. |
With the new standard GUI, a straightforward screen layout displays information in an efficient and comfortable manner that provides intuitive, nondistracting, and accurate view control, with rapid access to critical functions. To begin, operators, engineers, supervisors, and systems administrators can complete tasks and orient themselves via buttons on the navigation panel, a horizontal array at the bottom of the screen that is always shown regardless of the displayed functional area (see bottom of Fig. 1). Selection of a navigation button provides access to groups of logically related tasks and equipment capabilities in functional areas devoted to:
- processing — displaying information and control capabilities for processing;
- system — system monitoring, maintenance, and diagnosis;
- recipes — recipe management;
- logs, setup, and database — user preferences, hardware and software configuration, global parameter specification, communications, and user account management; and
- alarms — access to an alarm and exception management area (Exception management provides access to and reporting of information on abnormal situations in equipment by defining exception conditions, each related to a significant abnormal situation.)
Multiple views associated with each navigation panel button enable quick and easy display of related information. Most equipment interfaces can be implemented using a single-layer-view hierarchy. Figure 1, with the processing button clicked in the navigation panel, shows a processing-cassette screen divided into title, information, and command panels.
Title panel
In compliance with the new standard, the new GUI must display the title panel at the top of all screens at all times regardless of the screen or subview selected (See Fig. 2 on p. 263). Certain basic information will always be displayed. Examples include current date and time, company logo, title of the currently displayed view, and a login-logout button. Optional items on display include the host communications status (e.g., Fig. 2 shows it to be SECS), recipe name, processing status, and light tower icons (i.e., the colored boxes at the far right). In addition to these required and optional items, some metrology tools, such as those manufactured by Nanometrics, add port, queued recipe, and process program identification (PPID) information, as shown in Fig. 2.
Information panel
The information panel sequentially displays one or more views of data and graphics that are logically related and grouped together to facilitate processing, maintenance, monitoring, trouble shooting, or other user and equipment tasks. It displays views available in each functional area of the GUI, accessed by selecting the navigation button. There are two methods for presenting and selecting multiple views in the selected area: displaying views (containing data, graphics, and control functions) on a single row of tabs, or providing buttons the user can select to display each view. In practice, users seem to prefer views on tabs, many of them remarking that tabs are familiar, intuitive metaphors.
Figure 3 on p. 264 shows the relationship between navigation panel buttons and tab views displayed on the information panel; user selection of a navigation button displays the views for that functional area of the GUI on the information panel, replacing previously displayed views.
Command panel
Each displayed view has its own command panel that provides global command buttons (e.g., open, save, save as, start job, pause, resume, etc.). When the user selects another view, the screen displays the corresponding command panel. Buttons, as well as other controls with functions more narrow in scope — say, for sorting one of several displayed lists, or for obtaining more detailed information about some part of the equipment —are placed directly on the view, not in the command panel.
GUI on a tool
Nanometrics adopted E95-0200 with the release of its new N2000 software platform. It took thousands of engineering man-hours to develop the new user interface and incorporate requested changes from users in the semiconductor and flat-panel display industries. Even more hours would have been spent on software design and development if a standard did not already exist.
 Figure 6. a) Nanometrics Semi standard processing-button data-all-tab view, b) Nanometrics Semi standard logs-button error-tab view. |
E95 allows some flexibility while still conforming to the standard GUI. For example, Fig. 4 on p. 264 shows the processing-navigation-button automatic-tab view on a Nanometrics tool. On this command panel are buttons that enable an operator to start one recipe while queuing another. In this view, the process-options button (on the right) gives other operators choices such as auto-print, auto-mapping, and auto-save. Figure 5 illustrates how Nanometrics implemented an information panel processing view via the processing-navigation-button and turbo-tab. Here, operators can press one of 26 recipe buttons and immediately start the recipe of their choice. They can also press the ID button within each recipe to enter lot information, or press the DB button to go to the database and select data based on the recipe. This "turbo" view is the default screen that the Nanometrics N2000 application initially displays upon start-up.
Figure 6a shows a view accessed by selecting the processing button and the data-all tab on the N2000; here, all elements including thickness data, video image, measurement position, and reflectance vs. wavelength data of a film measurement are shown in real time. Similarly, a logs-button error-tab view reveals all system errors for quick troubleshooting and software enhancement (Fig. 6b).
Operating systems
Operating systems also affect, to a certain degree, the appearance and performance of the application. Early on in the semiconductor industry, transistor-transistor logic (TTL) governed most control panels and operator interfaces with lots of rotary dials, analog gauges, and red LEDs. Eventually, firmware was introduced and was upgraded by replacing EPROMS or ROMS. As personal computers became less costly and easier to use, engineers adapted them to control processing tools. First there was the small black-and-white screen, followed by larger color monitors. Many of these first-generation personal computer controllers used custom operating systems. Over time, equipment manufacturers have migrated toward commercially available operating systems, such as Windows NT.
There is now a movement toward Windows operating systems for most pieces of semiconductor manufacturing equipment. Some manufacturers have hung in there with DOS as long as they could, while other companies took the plunge early and moved on to Windows or OS/2. As manufacturing tools become more complex, requiring simultaneous execution of many processes, there is an even greater incentive to move to Windows NT and, soon, to Windows 2000.
Future Semi guideline
Is Semi E95 explicit enough? It does not specify items such as colors, button types, icon designs, communication capabilities, or sound, but this information is on the horizon. A year from now, Semi Draft Document No. 2990: "User Interface Style Guide," will address these issues and many other important topics. It will provide real-world practical design guidelines, techniques, methodologies, and suggestions aimed at reducing the time and effort required to design, implement, and deploy easy-to-use, efficient, and automated manufacturing GUIs. Companies can help contribute to Document No. 2990 by offering customer input and feedback to the guideline committee.
Conclusion
As companies throughout the industry adopt E95, comparable tools from various competitors will have similar GUIs, offering a unified approach to GUI design. In the future, the purchaser's personal software preferences will be much less of a factor in purchasing a tool. Instead, due to a common GUI, the purchase decision will be fully based on performance and cost of ownership.
Shawn Jipp has worked at Fairchild Semiconductor, AMD, Cypress Semiconductor, and AG Associates. Jipp is product marketing manager for stand-alone metrology tools at Nanometrics Inc., 310 DeGuigne Drive, Sunnyvale, CA 94086; ph 408/746-1600, fax 408/720-0196, e-mail [email protected].
Frank Summers is a member of the ISA, ICS, and Usability Professionals of America, a voting member of Semi Standards International, and chair of the Semi North American Human/Computer Interface Task Force. Summers is president and CTO of Industrial-Strength Graphics Inc.; e-mail [email protected].
History of Semi E95-0200
The Semi Japan Human-Computer Interface (HCI) Task Force first proposed E95, based on the Sematech "SCC User-Interface Style Guide 1.0" that was published in 1992. SCC is an acronym for Strategic Cell Controller, and the document is commonly referred to as SCC 1.
This document was the result of extensive research into the ergonomics of presenting information in an easy-to-use and consistent manner, and providing effective control functionality to users. It specifically addresses technical and perceptual issues involved in using operating systems with capabilities for multiple windows when using a touchscreen as the sole input device. Although written for applications to monitor and supervise a group of tools in a work cell or bay, the precepts have proven equally useful at the equipment level.
Champion of and contributor to SCC 1, Dwight Miller of Sandia National Laboratories, Albuquerque, NM,. was extolling user interface consistency and ease of use as far back as the 1980s. Miller organized and chaired the first Semi HCI Task Force, which met a number of times in 1993 and 1994. Despite a high level of interest from chipmakers and equipment suppliers, few task force members could devote time to the effort, and no further work was done.
Shortly thereafter, working groups in the Japan Electronics Industry Development Association (JEIDA) and other Japanese organizations started discussing the need for a GUI standard for 300mm semiconductor processing equipment. This, in turn, led to the establishment of the Semi Japan HCI Task Force and the subsequent proposal of E95 in 1997.
The standard was written collaboratively by the Semi Japan HCI Task Force and the North American HCI Task Force, with additional help from European experts. While retaining the shallow-view hierarchy and rapid navigation capabilities rooted in SCC 1, E95 was enhanced by greatly expanding the number of views available and by broadening its applicability to all semiconductor manufacturing equipment that has GUIs.
A number of characteristics make E95 unique. It is designed to be neutral to the platform, operating system, and tool. Its "look and feel" has been optimized for touchscreen operation while not compromising easy use with other pointing devices and keyboards. The architecture, screen layout, and navigation model are user- and task-oriented, and it is the first GUI standard tightly focused on production, maintenance, and troubleshooting work requirements.
After more than three years of work, the document was approved for publication as a Global Standard on September 3, 1999. The final and authoritative specification was published in February 2000.