Patent Application
20050192690
1. Field of Invention
This invention relates generally to wafer testing in a semiconductor manufacturing facility and, more particularly, to integration of the Manufacturing Execution System (MES) with test equipment to improve the configuration and relationship between the wafer product and the test equipment.
2. Description of Related Art
Correct test programs are very important to maximum yield and customer satisfaction. Many methods and in-house systems are implemented to address this issue, but they do not perform well or are complicated to maintain and are manpower intensive. Current equipment and recipe modeling can not specify the exact test program and equipment configuration for all current products. Complex, high-maintenance extra systems and tables outside the MES are used to specify a test recipe, but some test recipes can not be specified exactly due to modeling limitation. Engineers now maintain the complex relationship between the product and capable testers.
The product, sort type, and probe card are all factors of test program selection but currently are not in the MES infrastructure. Current Chip Probing (CP) Manufacturing Execution System (MES) infrastructures include Poseidon (IBM's factory automation programming system) and PROMIS and their extra table or systems. PROMIS is an IBM product that provides an MES for batch, semi-batch and discrete manufacturing. PROMIS' manufacturing execution software gives visibility and control over the plant floor. Poseidon does not include the test program (test recipe) in the MES infrastructure. Only one tool group can be mapped to one product-sort, and one tool group may include many testers (test groups) that belong to different tester types (equipment). Thus, the relation between tool group and equipment is very complicated, and any change of tester configuration will impact many tool groups. There are many equipment types and tool groups currently, and one change of tester configuration can require the need to revise a large number of tool groups concurrently at considerable cost and time.
Poseidon has an extra table called a “traveler sheet” that maintains the test recipe information outside the MES, but only one product-sort can map to one test program. Since the test program is not embedded in the MES, the information cannot be applied to operation flow directly. Moreover, this model is not enough to specify the correct test program because the device under test (dut) property of a probe card will impact the test program selection.
In another infrastructure model type in PROMIS, alternative recipe and capability concepts are applied to the infrastructure to simplify the complicated relationship between the tool group and the equipment. This allows one product-sort to map several capabilities and one capability only includes the testers with same equipment type. This model reduces the quantity of capability (tool groups) resulting in easier maintenance of equipment configuration and uses product parameter to maintain the relation in test program version control.
Neither model covers the factor of the probe card's dut for test recipe control, and they cannot be applied to operation flow directly in the MES because they cannot be modeled into MES's infrastructure. Moreover, even when alternative recipe and capability concepts are applied to PROMIS' infrastructure for simplification, the tester capability model remains complex, not native, and has many extra routes created for the products with same flow due to the different capabilities. Thus a new model infrastructure system and method is needed to resolve problems of the current models. This invention provides the solution.
In U.S. Pat. No. 6,334,215 (Barker et al.) a methodology for migration of legacy application to new product architectures is discussed. In U.S. Pat. No. 6,263,255 (Tan et al.) a process control method for semiconductor manufacturing is discussed. In U.S. Pat. No. 5,867,389 (Hamada et al.) a substrate processing management system with recipe copying is discussed.
This invention's overall objective is to provide a method for relating the test recipe, product, and test equipment. It is a more specific objective to include the test recipe and test material model within the Manufacturing Execution System (MES) infrastructure. Another objective is to be able to set the exact test recipe according to the product class, sort stage, and test data within the MES. Still other objectives are to provide the capability to set the test equipment's configuration so that the correct tester is always used and to provide the capability to request the required test equipment's configuration for each product. A final objective is to provide for the test equipment's capability status. The satisfaction of these objectives will enhance quality control and simplify system maintenance.
This invention will be described with reference to the accompanying drawings, wherein:
The product, sort type, and probe card are all factors of test program selection. In the prior art, the current Chip Probing (CP) software programs used in the Manufacturing Execution System (MES) infrastructure are software products Poseidon, IBM's factory automation programming system, and PROMIS, IBM's programming product that provides an MES for batch, semi-batch and discrete manufacturing, and manufacturing execution software that gives visibility and control over the plant floor.
Poseidon does not include test program (test recipe) in its infrastructure.
In the Poseidon model an extra table called “traveler sheet” is used to maintain the test recipe information outside the MES and is shown in
In the PROMIS program, the “alternative recipe” and “capability” concepts are applied to PROMIS' infrastructure to simplify the complicated relation between tool group and equipment. Seen in
Neither model covers the factor of the probe card's dut for test recipe control nor can they be applied to operation flow directly in the MES because they cannot be modeled into MES's infrastructure. A new model infrastructure system and method are needed to solve the current problems. This invention provides that new infrastructure design solution. It sets the exact test recipe according to product class, sort stage, and test data within the MES as well as provides the capability to set the test equipment's configuration.
For the new implementation, the Silicon View program called SiView, an off the shelf MES program by IBM that controls the production process at the wafer level, is the 300 mm Chip Probing (CP) MES of choice. SiView is compatible with many current systems and is extendable for this implementation and other functions. It allows for using an off-the-shelf product that requires minimal coding and reduced maintenance for the MES. This reduces overall cost greatly. A simplified model to implement the initial version of SiView to make it compatible with current systems I-EDA and PCMS is shown in
An understanding of the class architecture of SiView's infrastructure of
For example:
The equipment list of this Equipment Recipe depends on the NameSpace —Tester Type (HP93K).
The Equipment Recipe ID is:
Now let us look at the equipment model. The Request Capability is defined in the upper/lower limit of recipe parameter inside Logic Recipe class. Present capability status is kept in a new status table. For example:
Equipment class is:
In a simplified model where other systems such as I-EDA and PCMS are supporting, the Bin definition ID/content is not defined in the SM. Instead, Bin Def ID is stated inside raw test file which is provided by the tester. The content is centrally defined in I-EDA and replicated into SiView. TSpec is also not defined in SiView and provided by central SBC/SBL languages project in I-EDA. The probe card and probe card group are not modeled in SiView but instead the present PCMS system information is used. This model can be used with the supporting systems until conversion is complete.
The method of the invention provides advantages over the prior art including eliminating significant wafer or yield loss due to an incorrect test recipe or having a wafer run on an incorrect tester, modeling actual behavior, modeling test program, product file and probe card into MES infrastructure, embedding recipe management directly into production routing including building tester configuration into product class so that real-time lot dispatching can run according to this tester configuration, providing the capability to set equipment configuration and to set the required equipment configuration for each product, modeling capability status into the properties of the equipment, and setting exact test recipe according to product, sort stage, and test material. The old equipment modeling did not specify exact test program and equipment configuration. Wrong test programs or testers might be selected due to limitation of the model or complexity of extra systems, and huge maintenance manpower spent on these extra tables beside MES. The new model will eliminate need for extra tables and systems, enhance quality control, simplify system maintenance, and improve throughput with the result of efficiency, improved yields, money saved, and enhanced customer satisfaction.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.
