Abstract:
A multi-chip package test apparatus is for testing a plurality of semiconductor packages including a plurality of flash memories and an application specific integrated circuit (ASIC) stacked on a single substrate. The multi-chip package test apparatus includes a plurality of test sockets configured to receive the plurality of semiconductor packages, respectively, a plurality of central processing units (CPUs) mounted on a test board and each configured to execute a package test of a respective one of the semiconductor packages received by the plurality of sockets, and a plurality of multiple access dynamic random access memory (DRAM) device operatively interposed between the CPUs and test sockets, respectively, each of the multiple access DRAM devices configured with separate memory areas for access by a respective CPU and a respective ASIC of the semiconductor packages.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    A claim of priority under 35 U.S.C. §119 has been made to Korean Patent Application No. 10-2010-0122379 filed Dec. 3, 2010, the entirety of which is incorporated by reference herein. 
       BACKGROUND 
       [0002]    The inventive concepts described herein relate to a multi-chip test device, and more particularly, relate to a multi-chip package test device capable of testing a multi-chip package with an Application Specific Integrated Circuit (ASIC) plus flash format using a Central Processing Unit (CPU) and a multiple access Dynamic Random Access Memory (DRAM) device mounted on a test board. 
         [0003]    Advances in electronic engineering technology and semiconductor integrated technologies have lead to increased miniaturization and multi-functionality of electronic devices. For example, a handheld telephone terminal such as a cellular phone inevitably necessitates a mobile communication function as well as a multimedia playback function. 
         [0004]    The miniaturization and multi-functionality of electronic devices can be implemented by system-on-chip (SOC) technology, in which a plurality of functions are integrated in one chip, and/or by multi-chip package (MCP) technology in which a plurality of semiconductor chips are packaged together as a single chip configuration. 
         [0005]    A semiconductor package including memory devices, such as a flash memory, DRAM, and Static Random Access Memory (SRAM) are subjected to various quality tests such as a burn-in test, a humidity test, and so on. Generally, the semiconductor package is powered by an electrical signal from a mother board on which various electronic apparatuses are disposed. 
         [0006]    Semiconductor package testing may include a reliability test, followed by board level testing. Reliability testing generally focuses on identifying defects (e.g., short-circuits) in the semiconductor package, and can including environmental testing, such as thermal testing and physical impact testing. On the other hand, board level testing is executed to determine whether the semiconductor package operates correctly when the package is mounted at a system level (e.g., on a system board.) 
         [0007]    In the case of reliability testing, the semiconductor package may be mounted on a test board connected to a test apparatus. A socket mount type test board may be used as the test board. 
         [0008]      FIG. 1  is a diagram illustrating a typical multi-chip package test apparatus. 
         [0009]    Referring to  FIG. 1 , a multi-chip package test apparatus  100  includes a tester  110  having a CPU  111  and a DRAM  115 , and a plurality of sockets  130  to  130   n . A plurality of multi-chip packages  120  to  12   n  are inserted in the sockets  130  to  130   n , respectively. Each of the multi-chip packages  120  to  120   n  includes a respective ASIC  121  to  12   n  and a respective flash memory  125  to  125   n.    
         [0010]    During a package test, the CPU  111  reads a test algorithm and tests functions on the ASICs  121  to  12   n  and the flash memories  125  to  125   n  in the multi-chip packages  120  to  120   n  using a test pattern. The DRAM  115  stores the test algorithm and test results of the ASICs  121  to  121   n  and the flash memories  125  to  125   n , and is used as a main memory of the CPU  111 . 
       SUMMARY 
       [0011]    In an embodiment of the inventive concept, a multi-chip package test apparatus is provided for testing a plurality of semiconductor packages including a plurality of flash memories and an application specific integrated circuit (ASIC) stacked on a single substrate. The multi-chip package test apparatus includes a plurality of test sockets configured to receive the plurality of semiconductor packages, respectively, a plurality of central processing units (CPUs) mounted on a test board and each configured to execute a package test of a respective one of the semiconductor packages received by the plurality of sockets; and a plurality of multiple access dynamic random access memory (DRAM) device operatively interposed between the CPUs and test sockets, respectively, each of the multiple access DRAM devices configured with separate memory areas for access by a respective CPU and a respective ASIC of the semiconductor packages. 
         [0012]    In another example embodiment of the inventive concept, a multi-chip package test method is provided which include inserting multi-chip packages each formed of an application specific integrated circuit (ASIC) and a flash memory into respective test sockets, testing functions on the multi-chip packages inserted into the respective test sockets, the testing executed by respective central processing units (CPUs), storing test results in an ASIC access areas of respective multiple access dynamic random access memory (DRAM) devices, comparing the test results with a reference value, the comparing executed by the respective CPUs, and evaluating and storing a pass/fail status of each of the multi-chip packages. 
         [0013]    In yet another embodiment of the inventive concept, a multi-chip package test apparatus is provided which includes a plurality of test sockets each configured to receive a package for testing, a plurality of multiple access dynamic access memory (DRAM) devices respectively connected to the plurality of test sockets by at least one first channel, and a plurality of central processing units (CPUs) respectively connected to the plurality of multiple access DRAM devices by at least one second channel. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0014]    The above and other objects and features will become apparent from the following description with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures unless otherwise specified, and wherein 
           [0015]      FIG. 1  is a diagram illustrating a typical multi-chip package test apparatus; 
           [0016]      FIG. 2  is a diagram illustrating a package solution in which packages are independently formed to have different package formats in a memory link architecture; 
           [0017]      FIG. 3  is a diagram illustrating a multi-chip package test apparatus according to an embodiment of the inventive concept; and 
           [0018]      FIG. 4  is a flowchart illustrating a multi-chip package test method according to an embodiment of the inventive concept. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The inventive concept is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the inventive concept are shown. This inventive concept may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout. 
         [0020]    It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the inventive concept. 
         [0021]    Spatially relative terms, such as “beneath”, “below”, “lower”, “under”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” or “under” other elements or features would then be oriented “above” the other elements or features. Thus, the terms “below” and “under” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. 
         [0022]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the inventive concept. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
         [0023]    It will be understood that when an element or layer is referred to as being “on”, “connected to”, “coupled to”, or “adjacent to” another element or layer, it can be directly on, connected, coupled, or adjacent to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to”, “directly coupled to”, or “immediately adjacent to” another element or layer, there are no intervening elements or layers present. 
         [0024]    Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present specification and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
         [0025]    In the typical multi-chip package test apparatus  100  of previously described  FIG. 1 , the apparatus  100  tests functions on the ASICs  121  to  121   n  and the flash memories  125  to  125   n  in the multi-chip packages  120  to  120   n  using a single CPU  111  and a single DRAM  115 . This however may however result in inefficient memory use and extended test time. That is, the CPU  111  and the DRAM  115  constituting the typical tester  110  are used to perform processes other than the package test, which can result inefficient memory use. Further, testing is performed sequentially with respect to the multi-chip packages  120  to  120   n , which can result in a relatively long test period. 
         [0026]      FIG. 2  is a diagram illustrating a package solution in which packages are independently formed of different package structures in a memory link architecture. 
         [0027]    Referring to  FIG. 2 , the first package  200   a  has a package-on-package (POP) structure and the second package  200   b  has a multi-chip package (MCP) structure. That is, the first and second packages  200   a  and  200   b  are formed independently to of different package structures in a memory link architecture. 
         [0028]    The memory link architecture includes one chip structure in which a multiple access DRAM memory device (e.g., OneDRAM®), an ASIC, and a flash memory are integrated. In the example of  FIG. 2 , the first package  200   a  has the POP structure formed by mounting a OneDRAM® 221 and a DRAM  223  on a package including a CPU  210 . 
         [0029]    As will be appreciated by those skilled in the art, the OneDRAM® 320 is a particular type of fusion memory including a fast, volatile memory (e.g., a DRAM) capable of enabling multiple access paths (e.g., by a CPU via one port and by an ASIC of a memory system via another port) to at least one shared memory area and at least one dedicated memory area. Hereafter, this type of memory—as best exemplified by the OneDRAM®—will be referred to as a “multiple access DRAM memory”. In the embodiments that follow, the OneDRAM® is adopted by way of example as the multiple access DRAM memory utilized in accordance with the inventive concept. 
         [0030]    Still referring to  FIG. 2 , the second package  200   b  has an MCP structure formed by stacking a plurality of flash memories  241  to  244  and an ASIC  230  on a single substrate, respectively. The plurality of flash memories  241  to  244  may be formed of NAND flash memory and/or NOR flash memory.  FIG. 2  shown an example in which there are four (4) flash memories, but the inventive concept is not limited in this manner. 
         [0031]    The first package  200   a  and the second package  200   b  are spaced apart from each other on a substrate or board. In the case of this inventive concept, a package test is made with respect to the ASIC  230  and the flash memories  241  to  244  constituting the second package  200   b  where the OneDRAM®  221  is separated there from in the memory link architecture. 
         [0032]      FIG. 3  is a diagram illustrating a multi-chip package test apparatus according to an embodiment of the inventive concept. 
         [0033]    Referring to  FIG. 3 , a multi-chip package test apparatus  300  according to an embodiment of the inventive concept includes a plurality of CPUs  310  to  310   n  mounted on a test board, a plurality of OneDRAM® devices  320  to  320   n , and a plurality of test sockets  360  to  360   n.    
         [0034]    During a package test, the CPUs  310  to  310   n  generate a test pattern using a test algorithm, and test functions on the ASICs  330  to  330   n  and the flash memories  340  to  340   n  mounted in the multi-chip packages  350  to  350   n.    
         [0035]    By using the OneDRAM® devices  320  to  320   n , data is routed between processors within a mobile device via a single chip, so that a need for two memory buffers is removed. Further, a data processing speed between a communication processor and a media processor within the mobile device is improved by taking a dual port approach. 
         [0036]    The OneDRAM® devices  320  to  320   n  include CPU access areas  321  to  321   n  only accessed by the CPUs  310  to  310   n , ASIC access areas only accessed by the ASICs  330  to  330   n , and shared areas exclusively accessed by respective ones of the CPUs  310  to  310   n  and the ASICs  330  to  330   n.    
         [0037]    During a package test, the OneDRAM® devices  320  to  320   n  may be disposed on channels CH 1  to CHn formed between the CPUs  310  to  310   n  and the test sockets  360  to  360   n , respectively. 
         [0038]    Accordingly, each CPU tests functions on an ASIC and a flash memory as the memory link architecture (refer to a dotted box) via a respective OneDRAM®. For example, a CPU  310  tests functions on an ASIC  330  and a flash memory  340  via OneDRAM  320 ®, and a CPU  310   n  tests functions on an ASIC  330   n  and a flash memory  340   n  via OneDRAM®  320   n.    
         [0039]    The test sockets  360  to  360   n  may be configured such that the multi-chip packages  350  to  350   n  with an ASIC plus flash memory format are inserted therein. 
         [0040]      FIG. 4  is a flowchart illustrating a multi-chip package test method according to an embodiment of the inventive concept. 
         [0041]    Below, an operation of a multi-chip package test apparatus according to an embodiment of the inventive concept will be more fully described with reference to accompanying drawings. 
         [0042]    In step S 10 , to prepare a package test, multi-chip packages  350  to  350   n  with an ASIC plus flash memory format are inserted into test sockets  360  to  360   n , respectively. 
         [0043]    In step S 20 , CPUs  310  to  310   n  test functions on the multi-chip packages  350  to  350   n  using a test pattern. Herein, the test pattern may be generated using a test algorithm. Each multi-chip package is formed of an ASIC and a flash memory as illustrated in  FIG. 3 . 
         [0044]    In an embodiment, the test algorithm may be stored in CPU access areas  321  to  321   n  of OneDRAM® devices  320  to  320   n . That is, the CPU access areas  321  to  321   n  of the OneDRAM® devices  320  to  320   n  are used as memories of the CPUs  310  to  310   n , so that test speed is increased because of the efficient use of memory during a package test. 
         [0045]    In step S 30 , after functions of the multi-chip packages  350  to  350   n  are tested, test results are stored in ASIC access areas  323  to  323   n  of the OneDRAM® devices  320  to  320   n , respectively. 
         [0046]    In step S 40 , the CPUs  310  to  310   n  read the test results from the ASIC access areas  323  to  323   n  and judge whether a test is performed exactly or correct, based upon a comparison result between the test results and a reference value. 
         [0047]    In the event that a test is made exactly, the multi-chip package test is judged to be passed. If a test is erroneous, the multi-chip package test is judged to be failed. In the latter case, failure information is stored to correct defects. The operation may be made in step S 50 . 
         [0048]    Accordingly, a package test is made in parallel using a plurality of CPUs  310  to  310   n  corresponding to packages, respectively. This means that a package test is performed with rapid speed as compared with the case that a plurality of packages are tested using one CPU. 
         [0049]    The above-disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments, which fall within the true spirit and scope. Thus, to the maximum extent allowed by law, the scope is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.