The SECS/GEM Semiconductor Gear Communication Normal/Generic Gear Mannequin interface was developed, maintained and revealed by SEMI Semiconductor Gear and Supplies Worldwide group, a non-profit group. By way of formal requirements, SEC/GEM might be referred to as SEMI normal E30, however most occasions it’s simply known as SECS/GEM normal or the GEM normal. “It refers back to the SEMI normal E30 which describes a generic mannequin for tools conduct and communication utilizing a subset of the message varieties outlined within the SEMI normal E5. Deployment of SECS/GEM interfaces will typically use TCP/IP networking as specified by SEMI Requirements E37 and E37.1 however RS-232 serial connections may also be used as described by normal E4. The latter is extra widespread for older tools. The SEMI requirements have shorthand names in addition to their official identifiers, thus E4, E5, and E37 are additionally known as SECS-I, SECS-II, and HSMS respectively” . Its essential focus is to productive economically and financially for each tools suppliers and machine producers “by defining a typical set of kit conduct and communications capabilities that present the performance and adaptability to help the manufacturing automation packages of semiconductor machine producers” . The SEC/GEM normal is an ordinary implementation of SECS-II normal.
Usually, the usual helps to outline situations and messages, it additionally permits manufacturing facility software program to have the ability to monitor and management equipments manufactured. Many of the equipments in photovoltaic, semiconductor, electronics meeting, flat panel show, floor mount know-how and different manufacturing industries world wide allow communication between manufacturing facility host software program with the machines as a way to monitor and/or management the machines, that is achieved by offering a GEM/SECS interface on the manufacturing equipments/machines. The usual might be utilized to nearly all equipments within the manufacturing trade as a result of the usual was written with few semiconductor-specific options in it.
SECS/GEM is a typical adopted communication interface that relies upon in its fashionable kind on sturdy TCP/IP web networking. The SECS/GEM protocol permits an in depth automation which helps to keep away from costly errors and relieves people of repetitive, lethal, tedious and error susceptible work, thereby making it’s of excessive worth within the Semiconductor and Electronics industries. The success tales of SECS/GEM are:
Institution and verification of kit setup earlier than processing for automated methods.
Switch of essential information in Measurement instruments with out operator transcription
Permits dealing with methods to switch supplies and coordinate motion routinely
Permits equipments to be successfully optimized and monitored by offering alarms and experiences for occasions.
The unique SEC/GEM protocols replicate an engineering method of directness and effectivity as they had been developed by hands-on implementers, however because the scope expanded, inputs from many firms and plenty of factors of view began to floor. This lack of coherence within the authentic and subsequent requirements made it appear to be the SEC/GEM normal was one thing developed by a number of groups for a slim set of necessities. When the entire SEC/GEM requirements are thought of generally, a whole lot of inconsistencies and imperfections are seen though this doesn’t depend when the worth of merchandise acquired is taken into account.
SECS/GEM Normal Utilization in Industries
The trade has been one of many main supporters of SECS/GEM and linked SEMI requirements. The GEM300 requirements which embrace the SEMI requirements E116, E94, E40, E87, E90 and reference the E39 normal had been outlined by the semiconductor front-end trade and a GEM30 normal upon which the GEM interface is constructed is offered for every of those requirements. With a view to implement manufacturing automation within the semiconductor trade, on each 300mm wafer manufacturing device, the SECS/GEM normal and a further GEM 300 requirements will probably be required.
Within the semiconductor back-end trade, a whole lot of tools makes use of the SEC/GEM normal and a few further requirements similar to
Particular tools mannequin for testing-Semi E122 and
Particular tools mannequin for handler- Semi E123 normal.
Floor Mount Know-how
Within the floor mount know-how trade, the SEC/GEM normal have been used for over 15 years, the SEC/GEM normal is essential for inspection of equipments, placement of chip, pasting of solder est.
The SEC/GEM normal was solely just lately formally adopted on this trade because the “Information for PV Gear Communication Interfaces (PVECI)”. In earlier years earlier than its official adoption, lot photovoltaic tools suppliers supported the usual. A brand new framework is outlined by a contemporary normal which makes use of the SEMI E148, SEMI E37 (HSMS) and different requirements.
In an automatic Semiconductor fabrication plant (a manufacturing facility the place gadgets similar to built-in circuits are manufactured- generally often known as “FAB”), the SEC/GEM interface can start and finish processing of kit, measure collected information, make modifications to variables and recipes are chosen for merchandise in a selected method;
SEMI Gear Communications Normal 1 Message Switch – this normal is utilized by SECS/GEM for communication between host and tools as outlined by RS-232. As a consequence of velocity limitations, the SEC-I normal is rapidly fading and being changed by the HSMS normal because of the following disadvantages;
Gradual transmission price of knowledge over RS-232 utilizing the SECS-I protocol.
Native space community (LAN) entry not offered by the usual.
Low noise immunity of RS-232.
SEMI Gear Communications Normal 2 Message Content material- Most performance and requirements utilized in SEC/Gem normal is outlined by the SEC-II normal. A definition for comparable tools communication functionality and conduct can be made accessible by this normal, within the semiconductor trade; it’s the usual for communication between tools and host. A variety of GEM compliant methods should not SECS-II compliant.
In SECS-II normal, message varieties are outlined which cowl a broad vary of capabilities that are outlined for particular objective or for basic use. A spread of operate and stream values are additionally offered in SECS-II normal outlined for customized use in conditions when the predefined message varieties should not required. The Stream and Perform collectively present what the message imply. SECS-II message varieties are categorized by Stream, e.g. Stream 1 is related to tools standing occasions and Stream 6 is related to tools monitoring and different occasions.
A reply could also be required for a despatched message, an odd quantity is used to point an asynchronously or independently despatched and this sort of message is known as Main message. A reply message to a beforehand despatched message is indicated with a fair operate worth a quantity forward of its corresponding main message operate worth and it’s referred to as a Secondary message. With a view to ship a number of messages with out ready for every reply earlier than sending one other message, a singular 4byte integer message header is used to affiliate a secondary and first reply message; this distinctive integer is ready by the sender.
SEMI normal Excessive Velocity Message Service-Single Session- the HSMS is now used rather than the SEC-I normal by SECS/GEM for communication between host and tools outlined utilizing TCP/IP community communication. A degree to level protocol for communication is outlined for the communication which permits just one shopper to 1 host to make use of a selected port at a selected time. It possesses the next benefits;
It offers larger velocity different to the SECS-I protocol
Excessive reliability and
Vast platform selections
The GEM or SEC/GEM normal specifies how particular duties, similar to reporting occasions, assortment of knowledge and administration of recipe of equipments are carried out utilizing SECS-II messages whereas speaking with the host.
All semiconductor manufacturing instruments have to comply with the SEMI SECS/GEM requirements to interface with the tools supervisor and MES (Manufacturing Execution System -Permits one or a number of tools GEM interfaces to speak on the similar time with a bunch system). These requirements embrace the semiconductor tools communication normal SECS-I or SECS-II, high-speed SECS message providers HSMS, and generic tools mannequin (GEM), and so on.
Moreover, to take full benefit of CIM Framework (Pc Integration Manufacturing-The CIM Framework defines a framework of parts that present the performance widespread throughout CIM purposes and permits integration of these purposes.), SEMI developed an object-based tools mannequin (OBEM) normal in order that the tools can talk with the CIM Framework immediately by technique invocation with out utilizing the SECS/GEM protocol. The OBEM normal focuses primarily on offering definitions, providers, and conduct of bodily and logical objects of which tools is often composed.
To speak with GEM succesful host, GEM equipments can talk utilizing one or each of the protocols listed under;
TCP/IP (utilizing the HSMS normal, SEMI E37)
RS-232 primarily based protocol (utilizing the SECS-I normal, SEMI E4).
Monitoring and controlling equipments with a GEM interface with the help of SECS-II messages can take minutes (and even seconds) as a way to make a connection for communication, that is specified by GEM. Monitoring the machine’s exercise for manufacturing facility GEM host software program offers the next advantages for tools producers.
Bettering of the machine’s high quality might be allotted extra money and time by offering a typical interface to all factories.
Processes and manufacturing might be improved by allocating extra money and time to them, reasonably than establishing communication to the machines.
The SECS/GEM Conceptual Mannequin
Under are descriptions of SEC/GEM message exchanges in conceptual mode as seen within the equipments.
Variables: Three totally different classes of variables are recognized in SEC/Gem protocol. The primary class of variables are Standing Variables, they’re read-only values which function communication channels, for instance readings from sensors or worth of clock to the host, they may also be used to explain equipments for Instance record of the collected information occasions which at that second are enabled for reporting. The second class is Knowledge Worth Variables and they’re much like Standing Variables within the sense that each of them are read-only information gadgets and the values which they maintain might be handed to the host. The distinction between the primary category- Standing Variables and the second category- Knowledge Worth Variables is that a it could typically maintain an invalid worth. The final class of variables is the Gear Fixed Worth variables, they aren’t fixed variables, they are often modified by the host to restricted values specified by the tools that are then communicated in a selected message format e.g. collected information or reported occasions.
This kind of message permits passage of an occasion to be notified to the host by the tools to e.g. standing change or course of completion. A beforehand outlined occasion report which comprises a hard and fast set of variable values was offered for older equipments whereas fashionable equipments offered help for dynamic occasion report which permits configuration of knowledge merchandise variables that are included within the set throughout communication of an occasion report by the host. The entire technique is highly effective and basic. E.g., after downloading a progress program, it may be used to speak consequence validation for a program as an asynchronous occasion. An in depth description is offered within the GEM normal of probably the most generally reported occasions which present modifications in course of state and modifications in management state.
An alarm is just not an occasion in that it exhibits an undesirable situation with two states; a transparent and set state. E.g., an alarm clear situation message could possibly be despatched as alarm set for a compressed air enter which requires an alarm if the air strain enter extends under the wanted quantity course of device that it depends on and if later the air strain was restored an alarm clear message could possibly be despatched. Experiences of alarm set and alarm clear circumstances are required as collected information occasions in SEC/GEM. The power to permit similar dynamic occasion report method and software program logic method to set circumstances of alarm and information context by the host makes this characteristic extra fascinating.
Management State Mannequin
A specification of management state mannequin that is sensible for making use of each automation and operator actions in a secure method offered for SEC/GEM interface. Distant management of the tools can’t be assumed by the host besides it’s allowed on the tools. In widespread circumstances e.g. upkeep efficiency or qualification of course of exercise with the host communication being ignored, the idea of the SECS/GEM interface offered is both off-line or on-line.
Distant Instructions might be despatched by the host on equipments to regulate tools actions similar to processing within the SECS/GEM interface. There’s similarity between a Distant Command and a programming process name within the sense that it’s doable to move arguments of knowledge gadgets as values for an indicated motion. E.g. Execution of a selected course of program. Distant Instructions have the wanted flexibility to permit automated manufacturing facility equipments to have the ability to perform numerous actions that are offered on the person interface device by utilizing the SECS/GEM. This characteristic is significantly appreciated by many manufacturing facility customers because it saves them money and time.
This characteristic offers experiences on chosen variable values every now and then, though the flexibility to make use of the hint reporting characteristic for detecting correct endpoint is missing however there’s typically a better expectation of its worth than is important since it could actually help a outstanding demonstration. A number of the the explanation why these options are missing throughout the tools system embrace; instrument intelligence, laptop proliferation and controllers of software program processes. It’s improper to imagine that one controlling program operating on a pc could have coordinated and instantaneous entry to all related info required. There’s want for good planning for time precision of compiled information between many sensor readings and administration with reference to course of initiation for the info collected, all this info must be generated from the beginning and put into the management system as a way to have an correct and exact report.
This characteristic is essential as a way to help acknowledgment of brief textual content messages and show message varieties, it has much less use in manufacturing space nevertheless it has help for demonstrations and instance packages. Most factories which can be utilizing SECS/GEM interface and have made investments in automation are doing their greatest to step away from manufacturing situations that rely on operator acknowledgment and displayed messages. Even within the ordinary factories the place all equipments are utilizing comparable languages, there’s excessive tendency that the navigation button for the menu to have the ability to see and approve terminal messages will probably be totally different for various kinds of manufacturing instruments. Subsequently deployment of operator station software program by the manufacturing facility is inspired if operator interplay is required as a substitute of deployment by every tools vendor.
Connection in SECS/GEM Protocol
Communication between the tools and the host is outlined utilizing a single connection. The SECS-I normal makes use of RS-232 serial ports for connection, whereas the HSMS makes use of TCP/IP for connection. Largely, a single is offered by the tools for use by one host alone. In SECS/GEM normal message varieties might be outlined for host use alone, for tools and for each side. Gear can hook up with a number of elements of different equipments to operate as a bunch and that is an environment friendly technique of bringing a number of elements of equipments collectively in a fabrication cell. Nevertheless in HSMS, there’s often impartial connection for a number of elements of kit. SECS/GEM additionally enable every machine identification to have a modulated message when sharing a connection however that is often discovered on methods with older RS-322 variations and never advisable for use on new deployments. Messages might be exchanged between host and tools as soon as a connection is established between the 2 of them and the connection can final for a really very long time, in some instances connections should not minimize besides it’s interrupted.
Communication in SECS/GEM Protocol
Usually within the implementation of SECS/GEM protocol communication, there are two events concerned; the tools and the host.
With a view to run GEM interface software program on its computer systems, any tools should comply and implement the SEMI requirements. Institution of communication on interface of SECS/GEM equipments is finished by the producer (manufacturing facility) which runs GEM host software program.
A number additionally known as line supervisor or station controller is a division or member of the Manufacturing Execution System (MES) of the manufacturing facility. A direct communication might be arrange by the host system on a single or amongst many GEM interfaces tools on the similar time utilizing SEMI E37.1 HSMS-SS normal (TCP/IP primarily based community communication) or SEMI E4 SECS-I normal (RS-232 primarily based serial communication) Though in most fashionable factories, the HSMS-SS normal is broadly adopted due to its comfort in such industries. Implementation of host-side communication have to be allowed for the host to have the ability to use the SECS/Gem interface however it isn’t vital for the host to adjust to the SEC/Gem requirements, since the usual is simply required for the expectation of the tools. To find out identification of software program/ tools, an internet recognition system is put in place to have the ability to confirm the identification of equipments.
Communication in SECS/GEM protocol is platform impartial i.e. it could actually make use of varied programming languages or working system and it’s completed by way of a serial cable connection or a community connection. For trade of knowledge, a connection on the host aspect is often arrange on a pc system which is made accessible by the manufacturing facility and connection on the tools aspect is often via laptop controller which is offered by the producer of the tools
Management in SECS/GEM Protocol
With a view to outline the extent of collaboration between the tools operator and the host, a management state mannequin is outlined for the SECS/GEM normal. To regulate the tools processing, instructions like EXIT, BEGIN and RETURN might be outlined for distant management to permit the host ship instructions. Many instructions might be outlined for equipments with their particular conduct when referred to as.
The static characteristic of equipments permits setting tools fixed, retrieving tools fixed and tools’s conduct to be monitored by the host. Gear static configuration is required for SECS/GEM state machines. Extra tools static variables might be configured by the host by way of the conduct of the equipments.
Operation Notification in SECS/GEM Protocol
With a view to monitor particular equipments operation, alarms on the Gear assortment have to be set by the host, this offers notification on vital, irregular actions/occasions and even when harmful occasions are detected and brought care of. A notification is distributed to the host by the tools for occasions which have been enabled for notification alone; any occasion not enabled for notification will be unable to ship a notification to the host. With a view to ship the notification and likewise to scale back community site visitors, a SECS-II messages format/normal is used to ship the notification. Additionally to watch sure actions by the tools the host can outline further occasions that are wanted by the SEC/GEM normal.
Knowledge Gathering in SECS/GEM Protocol
Six totally different strategies of knowledge assortment are outlined by SECS/GEM. Right here, there’s a mounted method of knowledge gathering the place potential to collect info from the host by tools is just not enabled however the potential to collect info by the host from the tools is allowed. The six strategies are described under;
Request of standing variable values which might be completed at any time.
Request of kit fixed values which might be completed at any time.
Request of report which comprises the variables of collected information, fixed tools values and the variable standing which might be completed at any time.
Transmission of Messages. The report information along with a group of occasions might be transmitted on the similar time if the host defines the experiences in the identical SECS-II message; this reduces the duty of the host throughout info ballot as a result of the characteristic permits information associated to every occasion to be despatched to the host to turn into accessible.
Ballot standing of kit. Gear every now and then/ ceaselessly transmits the standing variable values outlined by the host at a set interval, which permits the tools standing to be polled by the host at every interval without having for permission.
Configuration of limits monitoring. This permits a notification to be despatched to the host by the tools every time a specified variable worth strikes throughout a host-defined boundary, with this there will probably be no want for the host to ballot harmful values. A definition of many restrict boundaries may also be made.
Course of Program (Recipe) Administration in SECS/GEM Protocol
A course of program “is the set of directions, settings, and parameters beneath management of the tools that decide the processing surroundings seen by the manufactured object (SEMI E30, four.2.6.1)” . The options of the Course of program administration embrace the next:
Downloading of course of program to the tools by host for storage on the tools.
Question of course of program for storage by host from the tools.
Deleting of course of program on the tools by host.
Request of obtainable course of packages by host.
Sending of course of program to the host by tools operator.
Request of course of program from the host by the tools operator.
Collection of course of program for execution by host utilizing a distant command PP-SELECT
Notification of host by tools operator on creation, edit, deletion and choice of course of program on tools.
Spooling in SECS/GEM Protocol
This permits info meant for the tools to queue throughout break in communication or communication failure; the queued information might be purged by the host when communication is restored. Configuration of queued info is finished by the host together with the queue dimension, queue info and restoration of queue info and switching of spooling options on or off.
When contemplating the efficiency of previous and new SECS/GEM requirements, the brand new normal permits the setup of collected information with specification of the message price in milliseconds by the host. Little community bandwidth can be utilized to switch a whole lot of information within the SECS-II and HSMS normal as a result of their message format could be very environment friendly. There are lots of components that have an effect on the precise information charges similar to SEC/GEM software program within the host and tools methods, community, and the for the pc. By way of efficiency, there was a limitation of 1 Hz hint for collected information in earlier variations of the SECS/GEM normal.