Patent Publication Number: US-2006004786-A1

Title: Design mechanism for semiconductor fab-wide data warehouse application

Description:
BACKGROUND  
      The present disclosure relates generally to the field of semiconductor product manufacturing and, more particularly, to a system and method for semiconductor manufacturing data warehousing and data management.  
      The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing have been needed. For example, an IC is formed by creating one or more devices (e.g., circuit components) on a substrate using a fabrication process. As the geometry of such devices is reduced to the submicron or deep submicron level, the IC&#39;s active device density (i.e., the number of devices per IC area) and functional density (i.e., the number of interconnected devices per IC area) has become limited by the fabrication process.  
      Furthermore, as the IC industry has matured, the various operations needed to produce an IC may be performed at different locations by a single company or by different companies that specialize in a particular area. This further increases the complexity of producing ICs, as companies and their customers may be separated not only geographically, but also by time zones, making effective communication more difficult. For example, a first company (e.g., an IC design house) may design a new IC, a second company (e.g., an IC foundry) may provide the processing facilities used to fabricate the design, and a third company may assemble and test the fabricated IC. A fourth company may handle the overall manufacturing of the IC, including coordination of the design, processing, assembly, and testing operations.  
      A semiconductor fabrication facility may have many different processes occurring simultaneously on a twenty-four hour, seven days per week schedule. Complete automation of product identification, product tracking, process status, process control, equipment control, and equipment status are necessary in order to effectively run a semiconductor fabrication facility. Many problems may occur during a process flow for a semiconductor product ranging from equipment problems, process problems, and facilities problems. Simple errors such as mis-processing of a product or plurality thereof may occur due to a misjudgment or other errors in the process flow of a product line.  
      Accordingly, what is needed is a system and method to provide a semiconductor manufacturing data warehouse with efficient insertion and retrieval of data to manufacturing equipment and processes. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  depicts a semiconductor manufacturing data warehouse system with efficient retrieval and insertion of data to manufacturing equipment and processes.  
       FIG. 2  depicts an example virtual integrated circuit fabrication system for implementing one embodiment of the present disclosure.  
       FIG. 3  depicts a more detailed example of the virtual integrated circuit fabrication system of  FIG. 2 .  
       FIG. 4  depicts an example computer system that may be used in a virtual integrated circuit fabrication system such as described in  FIGS. 2 and 3 .  
       FIG. 5  is another embodiment of the semiconductor manufacturing data warehouse system of  FIG. 1 .  
       FIG. 6  illustrates a more detailed example of the system of  FIG. 5 .  
       FIG. 7  is a flowchart for query of data from the database for a specified date.  
       FIG. 8  provides sample code for executing the query of  FIG. 6 .  
    
    
     DETAILED DESCRIPTION  
      The present disclosure relates generally to the field of semiconductor manufacturing and, more particularly, to a system and method for providing a semiconductor manufacturing data warehouse with efficient retrieval and insertion of data to manufacturing equipment and processes. It is understood, however, that the following disclosure provides many different embodiments, or examples, for implementing different features of the disclosure. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.  
      Referring to  FIG. 1 , in one embodiment, a semiconductor manufacturing data warehouse system  100  with efficient insertion and retrieval of data from manufacturing equipment and processes is shown. System  100  collects data from at least one process tool  102  through data collector  104 . Process tool(s)  102  may include any type of semiconductor or industrial type of manufacturing system that may perform a specified set of tasks that may help to fabricate a product. Process tool(s)  102  may include metrology equipment that may be used to gather data from a product such as material compositions, film thickness, surface contamination, dimensional measurements, and any other variable that may be measured by a metrology tool. Process tool(s)  102  may include metrology equipment as a sub-component of a cluster tool where a plurality of processes may be executed by a single process tool.  
      Data collector  104  stores the data collected from process tool(s)  102  into predefined areas  106  in storage entity  108 . Data is stored in a first predefined area until the data storage is complete for such predefined area, at which time data storage for the next predefined area begins. The predefined areas may be defined by various factors. For example, the predefined areas may be associated with data collected for a period of time (for example, a day or a week), number of lots process by a tool, or a storage area size. Once the data storage for a predefined area  106  is complete, data may be accessed from such predefined area at any time by a data inquirer  110  independent from the data collection and storing conducted by data collector  104 .  
      Referring now to  FIG. 2 , a virtual IC fabrication system (a “virtual fab”)  200  is one example of a system within which the data warehousing system of  FIG. 1  may be used. The virtual fab  200  includes a plurality of entities  202 ,  204 ,  206 ,  208 ,  210 ,  212 ,  214 , . . . , N that are connected by a communications network  216 . The network  216  may be a single network or may be a variety of different networks, such as an intranet and the Internet, and may include both wireline and wireless communication channels.  
      In virtual fab  200 , the entity  202  represents a service system for service collaboration and provision, the entity  204  represents a customer, the entity  206  represents an engineer, the entity  208  represents a design/laboratory (lab) facility for IC design and testing, the entity  210  represents a fabrication (fab) facility, the entity  212  represents a process (e.g., an automated fabrication process), and the entity  214  represents another virtual fab (e.g., a virtual fab belonging to a subsidiary or a business partner). Each entity may interact with other entities and may provide services to and/or receive services from the other entities.  
      For purposes of illustration, each entity  202 - 212  may be referred to as an internal entity (e.g., the engineer  202  or the system process  212 ) that forms a portion of the virtual fab  200  or may be referred to as an external entity (e.g., the customer  204 ) that interacts with the virtual fab  200 . Some entities may be both internal and external. For example, customer  204  may provide updated mask sets (internal) and may purchase the final products/services (external) also. It is understood that the entities  202 - 212  may be concentrated at a single location or may be distributed, and that some entities may be incorporated into other entities. In addition, each entity  202 - 212  may be associated with system identification information that allows access to information within the system to be controlled based upon authority levels associated with each entities identification information.  
      The virtual fab  200  enables interaction among the entities  202 - 212  for the purpose of IC manufacturing, as well as the provision of services. In the present example, IC manufacturing includes receiving a customer&#39;s IC order and the associated operations needed to produce the ordered ICs and send them to the customer  204 , such as the design, fabrication, testing, and shipping of the ICs.  
      One of the services provided by the virtual fab  200  may enable collaboration and information access in such areas as design, engineering, and logistics. For example, in the design area, the customer  204  may be given access to information and tools related to the design of their product via the service system  202 . The tools may enable the customer  204  to perform yield enhancement analyses, view layout information, and obtain similar information. In the engineering area, the engineer  206  may collaborate with other engineers using fabrication information regarding pilot yield runs, risk analysis, quality, and reliability. The logistics area may provide the customer  204  with fabrication status, testing results, order handling, and shipping dates. It is understood that these areas are exemplary, and that more or less information may be made available via the virtual fab  200  as desired.  
      Another service provided by the virtual fab  200  may integrate systems between facilities, such as between the design/lab facility  208  and the fab facility  210 . Such integration enables facilities to coordinate their activities. For example, integrating the design/lab facility  208  and the fab facility  210  may enable design information to be incorporated more efficiently into the fabrication process, and may enable data from the fabrication process to be returned to the design/lab facility  210  for evaluation and incorporation into later versions of an IC. The process  212  may represent any process operating within the virtual fab  200 .  
      Referring now to  FIG. 3 , in another embodiment of the virtual fab  200 , the entities  202 - 212  are described in greater detail. The service system  202  provides an interface between the customer and the IC manufacturing operations. For example, the service system  202  may include customer service personnel  316 , a logistics system  318  for order handling and tracking, and a customer interface  320  for enabling a customer to directly access various aspects of an order.  
      The logistics system  318  may include a work-in-process (WIP) inventory system  324 , a product data management system  326 , a lot control system  328 , and a manufacturing execution system (MES)  330 . The WIP inventory system  324  may track working lots using a database. The product data management system  326  may manage product data and maintain product information in a product database. The product database could include product categories (e.g., part, part numbers, and associated information), as well as a set of process stages that are associated with each category of products. The lot control system  328  may convert a process stage to its corresponding process steps.  
      The MES  330  may be an integrated computer system representing the methods and tools used to accomplish production. In the present example, the primary functions of the MES  330  may include collecting data in real time, organizing and storing the data in a centralized database, work order management, workstation management, process management, inventory tracking, and document control. The MES  330  may be connected to other systems both within the service system  202  and outside of the service system  302 . Examples of the MES  330  include Promis (Brooks Automation Inc. of Massachusetts), Workstream (Applied Materials, Inc. of California), Poseidon (IBM Corporation of New York), and Mirl-MES (Mechanical Industry Research Laboratories of Taiwan). Each MES may have a different application area. For example, Mirl-MES may be used in applications involving packaging, liquid crystal displays (LCDs), and printed circuit boards (PCBs), while Promis, Workstream, and Poseidon may be used for IC fabrication and thin film transistor LCD (TFT-LCD) applications. The MES  330  may include such information as a process step sequence for each product.  
      The customer interface  320  may include an online system  332  and an order management system  334 . The online system  332  may function as an interface to communicate with the customer  204 , other systems within the service system  202 , supporting databases (not shown), and other entities  306 - 312 . The order management system  334  may manage client orders and may be associated with a supporting database (not shown) to maintain client information and associated order information.  
      Portions of the service system  202 , such as the customer interface  320  and order management system  334  may be associated with a computer system  322 . In some embodiments, the computer system  322  may include multiple computers, some of which may operate as servers to provide services to the customer  204  or other entities. The service system  202  may also provide such services as identification validation and access control, both to prevent unauthorized users from accessing data and to ensure that an authorized customer may access only their own data.  
      The customer  204  may obtain information about the manufacturing of its ICs via the virtual fab  300  using a computer system  336 . In the present example, the customer  204  may access the various entities  202 ,  204 - 212 , of the virtual fab  200  through the customer interface  320  provided by the service system  202 . However, in some situations, it may be desirable to enable the customer  204  to access other entities without going through the customer interface  320 . For example, the customer  204  may directly access the fab facility  210  to obtain fabrication related data.  
      The engineer  206  may collaborate in the IC manufacturing process with other entities of the virtual fab  200  using a computer system  338 . The virtual fab  200  enables the engineer  206  to collaborate with other engineers and the design/lab facility  208  in IC design and testing, to monitor fabrication processes at the fab facility  210 , and to obtain information regarding test runs, yields, etc. In some embodiments, the engineer  206  may communicate directly with the customer  204  via the virtual fab  200  to address design issues and other concerns.  
      The design/lab facility  208  provides IC design and testing services that may be accessed by other entities via the virtual fab  200 . The design/lab facility  208  may include a computer system  340  and various IC design and testing tools  102 . The IC design and testing tools  102  may include both software and hardware.  
      The fab facility  210  enables the fabrication of ICs. Control of various aspects of the fabrication process, as well as data collected during the fabrication process, may be accessed via the virtual fab  200 . The fab facility  210  may include a computer system  344  and various fabrication hardware and software tools and equipment  102 . For example, the fab facility  210  may include an ion implantation tool, a chemical vapor deposition tool, a thermal oxidation tool, a sputtering tool, and various optical imaging systems, as well as the software needed to control these components.  
      The process  212  may represent any process or operation that occurs within the virtual fab  200 . For example, the process  212  may be an order process that receives an IC order from the customer  204  via the service system  202 , a fabrication process that runs within the fab facility  210 , a design process executed by the engineer  206  using the design/lab facility  208 , or a communications protocol that facilities communications between the various entities  202 - 212 .  
      It is understood that the entities  202 - 212  of the virtual fab  200 , as well as their described interconnections, are for purposes of illustration only. For example, it is envisioned that more or fewer entities, both internal and external, may exist within the virtual fab  300 , and that some entities may be incorporated into other entities or distributed. For example, the service system  202  may be distributed among the various entities  206 - 210 .  
      Referring now to  FIG. 4 , an exemplary computer  400  may be used to implement one or more portions of the embodiments, including the implementation of the semiconductor manufacturing data warehousing system  100  through MES  330  in virtual fab  200 . The computer  400  may include a central processing unit (CPU)  402 , a memory unit  404 , an input/output (I/O) device  406 , and a network interface  408 . The network interface may be, for example, one or more network interface cards (NICs). The components  402 ,  404 ,  406 , and  408  are interconnected by a bus system  410 . It is understood that the computer may be differently configured and that each of the listed components may actually represent several different components. For example, the CPU  402  may actually represent a multi-processor or a distributed processing system; the memory unit  404  may include different levels of cache memory, main memory, hard disks, and remote storage locations; and the I/O device  406  may include monitors, keyboards, and the like.  
      The computer  400  may be connected to a network  412 , which may be connected to the networks  216  ( FIGS. 2, 3 ). The network  412  may be, for example, a complete network or a subnet of a local area network, a company wide intranet, and/or the Internet. The computer  400  may be identified on the network  412  by an address or a combination of addresses, such as a media control access (MAC) address associated with the network interface  408  and an internet protocol (IP) address. Because the computer  400  may be connected to the network  412 , certain components may, at times, be shared with other devices  414 ,  416 . Therefore, a wide range of flexibility is anticipated in the configuration of the computer. Furthermore, it is understood that, in some implementations, the computer  400  may act as a server to other devices  414 ,  416 . The devices  414 ,  416  may be computers, personal data assistants, wired or cellular telephones, or any other device able to communicate with the computer  400 .  
      Referring now to  FIG. 5 , a system  500  is a more detailed embodiment of data warrehouse system  100  for collecting data from any location in virtual fab  200 , which utilizes computer integrated manufacturing (CIM). CIM is the term used to describe the automation of a semiconductor manufacturing facility, with all processes functioning under computer control and digital information tying them together. An example CIM implementation may include computer-aided design/computer-aided manufacturing equipment, computer-aided process planning capabilities, computer numerical control machine tools, direct numerical control machine tools, flexible machining systems, automated storage and retrieval systems, automated guided vehicles, use of robotics and automated conveyance, computerized scheduling and production control business systems and an MES.  
      In the present embodiment, storage entity  108  may include a MES  330  database  502 . Database  502  may be configured to receive enormous amounts of data, such as data from process tool(s)  102 , product information, process information, product test information, user input information, and any other information or data that may be recorded. Database  502  may be configured to be continually being updated.  
      Process tool(s)  102  may include any type of semiconductor or industrial type of manufacturing system that may perform a specified set of tasks that may help to fabricate a product. For example, a process tool  102  may be a tool in design/lab facility  208  or a fab facility  210 . Therefore, in the case of semiconductor fabrication where many different material layers are stacked upon each other, a plurality of layers along with a plurality of measurements may be executed by a process tool(s)  102 .  
      Generally, there may be three major considerations for CIM system design, which may include the reduction of cross-influence of data inquiry and data insertion into a database  502 , the efficiency of the response time for data insertion, and the efficiency of the response time for data inquiry. The present embodiment employs a relational database as database  502  utilizing sequential query language (SQL) to communicate with a database  502 . According to ANSI (American National Standards Institute), SQL is the standard language for relational database management systems. SQL statements are used to perform tasks such as update data on a database, or retrieve data from a database. Some common relational database management systems that use SQL are produced or distributed by several companies, such as Oracle Corporation of Redwood Shores, California, Sybase Inc. of California, IBM Corporation of New York, and Microsoft Corporation of Washington. Database  502  may be implement on any hardware with sufficient capacity. Some example platforms capable of being used with the systems that use SQL mentioned above are Window NT, Unix platforms or OpenVMS platforms, all available from Hewlett-Packard Company of California.  
      The present embodiment may provide separate database channels coupled to database  502  for data insertion and data inquiry; data inquirer  514  or a plurality thereof and data insertion channel  516  or a plurality thereof. In one embodiment, the data collectors  104  may build a plurality of sequential query language (SQL) commands by employing a bind variables technique. Bind variables improves performance, wherein a SQL command (An SQL command included: query, insert and update) may be prepared once and executed multiple times, without loosing data associated with the SQL command. The bind variables technique may join together a plurality of associated variables, files, and other clusters of information. For example, bind variables techniques may provide a lookup table and/or cache wherein all associated entities of a variable may reside closely linked to a variable, file, query, and/or any other clusters of information. The use of bind variables improves the cache-hit rate of SQL command for database  502 , which may have a cache prepared prior to the creation of the queries. Database  502 , which supports the bind variables may parse the SQL command by substituting input bind variables into parsed code created at a prior time. If the same SQL command executes a plurality of times, then even with different values for the input bind variables, database  502  may have the code cached. Therefore, further parsing of the SQL command may not be required. However, if the input bind variables are not employed, then database  502  may parse the SQL command each time wherein every access of the database may be slightly different each time. Furthermore, the code for every interaction with the database  502  may be slightly different for each SQL command which may result in congestion of the cache.  
      A plurality of smaller tables or caches with links to various variables may be employed to enhance the loading rate of SQL parsing information and the execution of a SQL command. The plurality of data collectors  104  and lookup data tables may effectively increase data insertion due to the small file size and linkage to various variables. In addition, in the present embodiment, the data table are divided into data groups. The data may be grouped by time (for example, for a fixed interval of time) or by some other characteristic (for example storage size, lot number, etc.).  
      Of course, it is understood that the use of the SQL command is not limited, and that other commands, queries, and/or other information manipulation commands may be employed associated with the data collectors  104 , the database  502 , and/or other entities.  
      The data collectors  104  may collect process data from a plurality of tool controller(s)  510  connected to process tool(s)  102  or collect process data directly from a plurality of process tool(s)  102  (stand-alone or clusters). For example, a parent data collector  104  may be assigned to a plurality of etch process, diffusion, thin film, or lithography process tool(s)  102 . Other data collectors  104  may be assigned to electrical probing and test systems. Data collectors  104  may be assigned to specific time intervals for data collection to a specific process tool  102 . Alternatively, the data collectors  104  may be assigned for each process tool  102  and may be coupled to a database  502  for a plurality of process tool(s)  102  through the virtual fab.  
      The tool controller  510  may be implemented in many forms. For example, tool controller  510  may be a system that resides in a computer integrated into a process tool  102  or may exist as a sub-component of a system providing supporting control for the process tool  102 . Data from the tool controller  510  may be sent to the data collectors  104  at a specified time or after a specified number of product pieces or semiconductor wafers have been processed by a process tool(s)  102 . Data collection by the tool controller(s)  510  and the data collectors  104  may occur sequentially, in parallel, and may be distributed asymmetrically throughout the virtual fab.  
      The time in which data may be sent from the tool controller  510  to the data collectors  104  may be event driven. For example, data could be sent from the tool controller  510  to the data collectors  104  after a process is complete for a single wafer or after a lot of wafers. In the case of a cluster of process tool(s)  102  where a plurality of processes may be combined into a single process equipment platform, data may be sent to the data collectors  104  from the tool controller  510  partitioned by process chamber on the cluster of process tool(s)  102  and/or the data maybe grouped according to all processes that may be combined in a cluster of process tool(s)  102 . The tool controller  510  and plurality thereof may collect and store process and equipment data for each lot, semiconductor wafer, or process piece. After each process in a process tool  102 , the data controller  510  may send data to the data collectors  104 . The tool controller  510  may record any and all information from a process tool  102  at any specified interval of time. The data uploaded from the tool controller  510  may be automatically and continuously grouped according to time by the data collectors  104 . The tool controller  510  may buffer or store any data from any process tool(s)  102  until an event triggers the tool controller  510  to transmit or download the data to the data collectors  104 . Buffering the data is useful, but not essential. The tool controller  510  may normalize any data collected from the process tool(s)  102  until all data from a lot, wafer, or processing piece may be completely processed by the process tool(s)  102 . Normalizing the data with respect to a plurality of baseline data may help to reduce the size of the data and, therefore, further speedup the ability to access the data from the tool controllers  510  to the data collectors  104 . Normalized data may be of smaller size and, therefore, allows for quick read and write operations between the tool controller  510  and the process tool(s)  102 .  
      Still referring to  FIG. 5 , access to the database  502  may be accomplished through the data inquirer  110 , which may be accessed by a controller  508 , either of which may be accomplished via remote access. A plurality of data inquirers  110  may be utilized. The at least two separate database channels  514  and  516 , one for data collection and one for data inquiry, allow for simultaneous, continuous parallel processing of process tool(s)  102  data collection and data inquirer  110 .  
      Tool controller  510  and process tool(s)  102  may be connected or linked by a tool link  514 . The tool link  514  may include a standard communication protocol known as the Semiconductor Equipment Communication Standard (SECS) or may be linked by any other suitable communications method. Other methods of communication between process tool(s)  102 , the tool controllers  510 , and the data collectors  104  may be through wireless protocols such as Bluetooth™ and IEEE 902.11 b, for example. Wireless communication protocols may be also employed by all components of the database  500  system, including database  502 , data collectors  104 , the data inquirer  110  and the remote server  508 .  
      Referring now to  FIG. 6 , system  600  illustrates the partitioning of database  502  into plurality of data tables  602 ,  604 ,  606 ,  608 , and  610 . Data inquirer  110  may access the data tables  602 - 610 . The data tables  602 - 610  may be grouped in numerous ways, including a specified time period. Partitioning collected data into a plurality of small data tables  602 - 610  may significantly increase the speed at which data may be accessed for analysis. All data during a specified time period that may correspond to specified data tables  602 - 610  may be saved in the same data tables  602 - 610  for a specified time.  
      In systems  500  and  600 , data inquirer  110  may process in parallel with the data collectors  104 . The finite amount of storage space in the database, organized in data groups, reduces the impact of backing up data in database  502 , because backing up and/or purging the data may be executed on a data group basis instead of on the entire database. For example, the table group storing the oldest data may be backed up and/or purged to prepare it for storing data during the next period. Therefore, a data group may be backed up and/or purged instead of backing up and/or purging all the data in the database to get free space. Also, the small data tables  602 - 610  allow for all operations including those in data collectors  104  and data inquirers  110  to be processed at very fast speeds, since small files are generally quicker and easier to process.  
      Referring now to  FIG. 7 , flowchart  700  provides an example process for determining the location of data associated with a specific date. For purpose of example only, it is assumed that data is being stored for a period of forty (40) days. Collected data is stored in a database in data tables, which are arranged into table groups. The variable “GroupNo” represents the number of table groups. In this example, there are four (4) table groups; “Table Group 0”  710 , “Table Group 1”  712 , “Table Group 2”  714  and “Table Group 3”  716 . Each table group includes ten (10) days worth of data organized in ten (10) data tables, one for each day. The number of days per table group is represents by the “Interval” variable. In this example the Interval is ten (10)).  
      To illustrate the process for determining the table group associated with data collected for a specific date (“Data Date”), the Data Date is Jan. 12, 2003 and the data collection initiation date is Jan. 1, 2003 (“Start Date”). Step  702  defines a “TotalDay” variable as the total number of days of data stored in database  502  since the Start Date. In the example, TotalDay is twelve (12) days. Decision  704  determines whether any data corresponding to the Data Date exists in the table groups by comparing the value of the TotalDay variable to the Interval multiplied by the GroupNo. If the value of the TotalDay variable is greater than the Interval multiplied by the GroupNo and, thus, the no corresponding data exists in the table groups, then the user may be notified of such and may access back-up data or take any other action in step  708 .  
      If the value of the TotalDay variable is less than or equal to the Interval multiplied by the GroupNo, then data is available for access and step  706  is executed to determine the table group associated with the Data Date. Step  706  utilizes the following: (1) the MOD or modulus function that returns the remainder when one number is divided by another; and (2) INT function that rounds a number down to the nearest integer. In the current example, in the MOD function, the devisor is the GroupNo variable and the numerator is the result of the INT function on TotalDay variable divided by the Interval variable. In this example, the result of the MOD function calculation is “1” representing “Table Group 1”  712 . If data from another date is desired, the process shown in flowchart  700  may be repeated.  
       FIG. 8  provides an example routine  800  for executing the process determining the table group associated with data for a specific date shown in steps  702 ,  704 ,  706  and  708  of flowchart  700 .  
       FIGS. 7 and 8  are representative example embodiments. Depending on the type and volume of data, the number of tables may vary and the existence or number of table groups may vary as well. The process shown in  FIG. 7  may be modified to accommodate the storing of data in certain data table or data groups.  
      Thus, the present disclosure provides a method for collecting, storing and accessing semiconductor manufacturing data in a storage entity. The method may include the collection of semiconductor manufacturing data from at least one process tool, storing it in a first predefined area of the storage entity until the storing of semiconductor manufacturing data in the first predefined area is complete. Then additional semiconductor manufacturing data may be stored in a second predefined area of the storage entity after the storing of semiconductor manufacturing data in the first predefined area is complete. After the storing of semiconductor manufacturing data in the first predefined area, the semiconductor manufacturing data in the first predefined area of in the storage entity may be accessed without interfering with the storing of the additional data.  
      In another embodiment, the present disclosure provides a computer-readable medium having stored thereon sequences of instruction for responding to a request for collecting, storing and accessing semiconductor manufacturing data in a storage entity is disclosed. The sequence of instructions may include instructions for performing the steps of collecting the semiconductor manufacturing data from at least one process tool and storing it in a first predetermined area in the storage entity until the storing of semiconductor manufacturing data in the first predefined area. Additional semiconductor manufacturing data may be stored in a second predefined area of the storage entity after the completion of storing of semiconductor manufacturing data in the first predefined area. After the completion of the storing of semiconductor manufacturing data in the first predefined area, the semiconductor manufacturing data in the first predefined area of in the storage entity may be accessed without interfering with the storing of the additional data in the second predetermined area.  
      The present disclosure also provides a system for collecting, storing and accessing semiconductor manufacturing data from at least one process tool in a storage entity is disclosed. The system may include a storage entity having at least two predetermined areas for storing data. The system may also include a data collector connected to the storage entity, and configured to receive semiconductor manufacturing data from at least one process tool, and to store the data in the at least two predetermined areas. The system may further include a data inquirer connected to the storage entity to access the semiconductor manufacturing data in each predetermined area in the storage entity after the storing of semiconductor manufacturing data each predefined area is complete.  
      The present disclosure has been described relative to a preferred embodiment. Improvements or modifications that become apparent to persons of ordinary skill in the art only after reading this disclosure are deemed within the spirit and scope of the application. It is understood that several modifications, changes and substitutions are intended in the foregoing disclosure and in some instances some features of the disclosure will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the disclosure.