Patent Publication Number: US-11022437-B2

Title: Leveling sensor, load port including the same, and method of leveling a load port

Description:
PRIORITY CLAIM AND CROSS-REFERENCE 
     This application is a continuation of U.S. patent application Ser. No. 16/275,994, filed on Feb. 14, 2019, entitled “Leveling Sensor, Load Port Including the Same, and Method of Leveling a Load Port,” which claims the benefit of U.S. Provisional Application No. 62/737,606, filed on Sep. 27, 2018, entitled “Load Port Leveling Sensor and Method of Using the Same,” which application is hereby incorporated herein by reference. 
    
    
     BACKGROUND 
     Semiconductor devices are used in a variety of electronic applications, such as, for example, personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductor layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon. 
     In order to process semiconductor devices, wafers on which the semiconductor devices are formed are transferred between various processing machines. During the transfer process, the wafers are secured in transport devices or pods. The wafers are moved from the transport pods to the processing machines using load ports, which automatically remove the wafers from the transport pods into the processing machines. Thus, the wafers are protected from exposure to contaminants, which might damage the semiconductor devices formed thereon. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. 
         FIG. 1  illustrates a plan view of a semiconductor processing apparatus, in accordance with some embodiments. 
         FIGS. 2A-2C  illustrate a cross-sectional view, a perspective view, and a bottom-up view, respectively, of a semiconductor wafer transport pod, in accordance with some embodiments. 
         FIGS. 3A-3C  illustrate a front view, a side view, and a top-down view, respectively, of a load port, in accordance with some embodiments. 
         FIG. 4  illustrates a flow diagram of a method for transferring semiconductor wafers between a semiconductor wafer transport pod and a semiconductor processing apparatus using a load port, in accordance with some embodiments. 
         FIGS. 5A and 5B  illustrate a front view and a back view of a sensor, in accordance with some embodiments. 
         FIGS. 6A-6C  illustrate front views of sensors, in accordance with some embodiments. 
         FIG. 7  illustrates a block diagram of a load port computer, in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. 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. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. 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. 
     Further, spatially relative terms, such as “beneath,” “below,” “lower,” “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. 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. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly. 
     Various embodiments provide improved sensors for determining whether a load port is level and whether vibration of the load port is excessive. The sensors include accelerometers, which determine whether there is movement or vibration of the load port and determine whether the load port is level. The sensors may provide visual, audio, and other warnings if the load port becomes out of level or vibrates excessively, thus these issues with the load port may be corrected. This helps to prevent defects caused by misalignment, excessive vibration, or the like of the load port and improves device yield for semiconductor wafers processed using load ports including the sensors. 
     Semiconductor devices are fabricated on semiconductor wafers by performing various processing steps, such as deposition, removal, patterning, electrical modification, and the like, on the semiconductor wafers. Semiconductor processing apparatuses are used to perform these processing steps on the semiconductor wafers. During this fabrication process, the semiconductor wafers are transported between various semiconductor processing apparatuses, which each perform different processing steps. Any contamination of the semiconductor wafers may cause defects in the semiconductor devices formed on the semiconductor wafers and can result in a drop in semiconductor device yield. As such, the semiconductor wafers are transported between the semiconductor processing apparatuses using transport pods, which have a controlled environment therein and prevent contamination of the semiconductor wafers. The semiconductor wafers are then transferred between the transport pods and the semiconductor processing apparatuses using load ports, which provide a controlled environment between the transport pod and the semiconductor processing apparatuses and prevent contamination of the semiconductor wafers during the process of transferring the semiconductor wafers between the transport pod and the semiconductor processing apparatuses. Misalignment of the load port, caused by, for example, the load port being unlevel, can compromise seals of the load port and allow contaminants to breach the load port and harm the semiconductor wafers. 
     Additionally, the semiconductor wafers can be bumped or scraped during the transportation process between semiconductor processing apparatuses, which may also cause defects in the semiconductor wafers and a semiconductor device yield drop. Unleveling of the load port and excessive vibration of the load port can both cause the semiconductor wafers to be bumped or scraped. As such, ensuring the load port is level and minimizing vibration of the load port serve to prevent defects in semiconductor wafers and increase semiconductor device yield. 
       FIG. 1  schematically illustrates a semiconductor processing apparatus  101  in accordance with an embodiment. The semiconductor processing apparatus  101  includes a first process chamber  103 , a second process chamber  105 , and a third process chamber  107  interconnected via a buffer chamber  109 . One or more load lock chambers  111  are connected to the buffer chamber  109 . The buffer chamber  109  and the load lock chambers  111  permit semiconductor wafers to be transferred between the first process chamber  103 , the second process chamber  105 , and the third process chamber  107  without breaking a vacuum between processes or chambers. 
     The semiconductor processing apparatus  101  may also include a transfer module  113  and load ports  115 . The load ports  115 , the transfer module  113 , and the load lock chambers  111  allow semiconductor wafers to be loaded and unloaded from the semiconductor processing apparatus  101  without exposing the transfer module  113 , the first process chamber  103 , the second process chamber  105 , or the third process chamber  107  to the ambient environment. The pressure of the load ports  115  may be about 1 atm, whereas the pressure of the buffer chamber  109  may be under a vacuum and may be much lower, such as less than about 10 Torr. 
     In operation, the semiconductor wafers are transferred into and out of the semiconductor processing apparatus  101 , either individually or in batches, via the load ports  115 . The semiconductor wafers are transferred from the load ports  115  to the load lock chambers  111  via the transfer module  113 . Once transferred into the load lock chambers  111 , the semiconductor wafers are isolated from the ambient environment. Typically, an inert gas such as nitrogen is purged through the load lock chamber  111 , and the load lock chamber  111  is pumped down to a low pressure or a vacuum. The load lock chamber  111  may be pumped to a pressure ranging from about 1.5 Torr to about 7.5 Torr to remove any air from the load lock chamber  111 . The semiconductor wafers are then transferred from the load lock chamber  111  to one or more of the first process chamber  103 , the second process chamber  105 , and the third process chamber  107 , which may be pumped down to a similar pressure as that of the load lock chambers  111  such that the pressure of the first process chamber  103 , the second process chamber  105 , and the third process chamber  107  are in equilibrium with the pressure of the load lock chambers  111  through the transfer module  113 . 
     The semiconductor wafers may be transferred from the load lock chambers  111  into a processing chamber, e.g., the first process chamber  103 , the second process chamber  105 , or the third process chamber  107 , using a belt, a robotic arm, or another transfer mechanism (not separately illustrated). The first process chamber  103 , the second process chamber  105 , and the third process chamber  107  may be equipped with heating elements, gas flow orifices, radio frequency coils, and other equipment (not separately illustrated) necessary to affect the desired processing steps. Each of the first process chamber  103 , the second process chamber  105 , and the third process chamber  107  may be configured for the same process or different processes as desired. It should be noted that  FIG. 1  illustrates a semiconductor processing apparatus  101  having three process chambers for illustrative purposes only. Other embodiments may include fewer or more process chambers. 
     In an embodiment, the semiconductor wafer is a semiconductor substrate. The semiconductor substrate may be a bulk silicon substrate, although it may include other semiconductor materials such as group III, group IV, and/or group V elements. In another embodiment, the semiconductor wafer is a semiconductor substrate on a carrier with a release layer between the semiconductor substrate and the carrier. The carrier may be a glass carrier, a ceramic carrier, or the like. The release layer may be formed of a polymer-based thermal release or thermosetting material, which can be removed to detach the semiconductor substrate from the carrier. In an embodiment, the release layer is formed of a polymer-based material such as epoxy, polyimide, ultraviolet (UV) light glue, or the like. The release layer may be applied as a liquid and cured. In alternative embodiments, the release layer is a laminate film that is laminated onto the carrier. In some embodiments, the semiconductor wafer includes passive and/or active devices, such as resistors and transistors. For example, the semiconductor wafer may be silicon substrate on a glass carrier with a release layer made from epoxy. 
     The semiconductor wafers are transported between the semiconductor processing apparatus  101  and other semiconductor processing apparatuses using transport pods. For example,  FIGS. 2A-2C  illustrate a cross-sectional view, a perspective view, and a bottom-up view, respectively, of a transport pod  201 , which may be a front opening unified pod (FOUP), a front opening shipping box (FOSB), a cassette, or the like. The transport pod  201  is configured to store a plurality of semiconductor wafers  209  at the same time in an airtight environment such that the semiconductor wafers  209  may be transferred between the various semiconductor processing apparatuses. 
     In order to load and unload the semiconductor wafers  209  from the transport pod  201 , a frame  205  of the transport pod  201  is sealed to a frame of a load port. Once the frame  205  is sealed to the load port, a transport pod door  203  of the transport pod  201 , such as a front-opening door, is robotically opened and the semiconductor wafers  209  are loaded or unloaded from the transport pod  201 . Once this process is complete, the transport pod door  203  is once again closed and sealed. 
     In accordance with some embodiments, the transport pod  201  may be sealed while storing the semiconductor wafers  209 , in order to prevent any contamination of the semiconductor wafers  209  contained therein. The transport pod  201  may be filled with ambient air while storing the semiconductor wafers  209 , which may be clean air at the pressure of one atmosphere. In accordance with alternative embodiments of the present disclosure, the transport pod  201  may be purged with nitrogen (N 2 ), which is substantially free from oxygen and moisture (for example, less than 1 volume percent, less than 0.1 percent, 0.01 percent, 0.001 percent, or lower). The transport pod  201  may be filled with nitrogen during the transportation of the transport pod  201  and while the semiconductor wafers  209  are stored therein. As illustrated in  FIG. 2C , the transport pod  201  may include ports  207 , which may be used to purge the transport pod  201  and/or fill the transport pod  201  with a gas, such as air, nitrogen, or the like. Purging the transport pod  201  with nitrogen gas or the like may be used to reduce humidity in the transport pod  201  and to increase Q-time (e.g., the maximum allowable time between semiconductor processes). 
       FIGS. 3A-3C  illustrate a front-view and a side view of a load port  301  and a top-down view of a pod transport plate  305  on a support  307 , respectively. The load port  301  is used to transfer the semiconductor wafers  209  between the transport pod  201  and the transfer module  113 . The load port  301  includes a load port door  303 , the pod transport plate  305 , and the support  307 . The load port door  303  is a movable door through which the semiconductor wafers  209  pass between the transport pod  201  and the transfer module  113 . The pod transport plate  305  is movably mounted on the support  307 . The pod transport plate  305  is a movable support on which the transport pod  201  is placed. The pod transport plate  305  may be movable between a first position and a second position in a first direction (indicated by the arrows  315  in  FIGS. 3B and 3C ). In some embodiments, the first position may be a position in which the transport pod  201  may be placed on or removed from the pod transport plate  305 . The second position may be a position in which the transport pod  201  is sealed to the load port  301 . The second position may be closer to the load port door  303  and the first position may be further from the load port door  303 . 
     The pod transport plate  305  may include nozzles  309 , a sensor  311 , and registration pins  313 . The nozzles  309  are connected to the ports  207  of a transport pod  201  placed on the pod transport plate  305  and may be used, for example, to purge the transport pod  201  using nitrogen gas or the like, as discussed above. The registration pins  313  interface with recesses (not separately illustrated) provided in the transport pod  201 , and may be used to align the transport pod  201  on the pod transport plate  305 . The registration pins  313  and/or other sensors (not separately illustrated) on the pod transport plate  305  may detect the position of the transport pod  201  on the pod transport plate  305  to ensure the transport pod  201  is properly aligned with the pod transport plate  305  before the pod transport plate  305  is moved from the first position to the second position. The pod transport plate  305  may further include clamps or locks (not separately illustrated) which maintain the position of the transport pod  201  on the pod transport plate  305  while the transport pod  201  is positioned on the pod transport plate  305 . 
     The sensor  311  may include an accelerometer (also referred to as a G sensor or a gravity sensor) or the like and may be used to detect the leveling of the load port  301 , vibration of the load port  301 , and the like. Although the sensor  311  is illustrated as being disposed on a top surface of the pod transport plate  305  in  FIGS. 3A-3C , in various embodiments, the sensor  311  may be disposed on a side surface of the pod transport plate  305 , on a surface of the support  307 , or in any other suitable position on the load port  301 . The sensor  311  detects the leveling and vibration of the load port  301  and provides a warning if either the leveling or the vibration of the load port  301  are outside of a prescribed range. The warning may include an audible alarm, a visual alarm, a phone call, or the like. Data from the sensor  311  may be sent to a computer (not separately illustrated) connected to the load port  301 , which may monitor the sensor  311  as well as other sensors included in the load port  301 . The load port  301  being unlevel or experiencing excessive vibration can cause damage to and defects in the semiconductor wafers  209  and can result in a drop in device yield. The defects or damage can be caused by contamination of the semiconductor wafers  209  due to improper sealing between the load port  301  and the transport pod  201  or the transfer module  113 ; bumping of the semiconductor wafers  209  with the transport pod  201 , a robotic arm or another transfer mechanism of the semiconductor processing apparatus due to vibration or misalignment, or the like. Including the sensor  311  in the load port  301  can prevent damage and defects to the semiconductor wafers  209  by detecting unleveling and vibration of the load port  301 , increasing device yield. 
     In some embodiments, the sensor  311  may be configured to be directly coupled to the load port  301 . For example, the load port  301  may include a socket or a USB cord, which may interface with an edge connector or a USB connector, respectively, of the sensor  311  (each of which is discussed in greater detail below with respect to  FIGS. 5A and 5B ). The load port  301  may further include a housing (not separately illustrated) configured to hold and protect the sensor  311 . 
     As illustrated in  FIG. 3B , the sensor  311  may be positioned on the load port  301  such that indicator lights (discussed in further detail below with respect to  FIGS. 5A-6C ) on the sensor  311  are visible and are not covered by the transport pod  201  or the like. In embodiments in which the load port  301  includes a housing for the sensor  311 , the housing may be configured such that the indicator lights of the sensor are not covered. As such, the indicator lights may be easily visible and may be used to aid in leveling the load port  301 . 
     In some embodiments, the load port  301  may further include a leveling mechanism (not separately illustrated). The leveling mechanism may level the load port  301  or the pod transport plate  305 . The leveling mechanism may include leveling jacks, leveling screws, or the like and may be manually actuated or electronically actuated (e.g., actuated through one or more motors). In embodiments in which the leveling mechanism is electronically actuated, the leveling mechanism may be controlled by a load port computer (discussed in greater detail below with respect to  FIG. 7 ) or the sensor  311  based on a level measurement of the sensor  311 . Accordingly, the load port  301  may be automatically leveled using the leveling mechanism in conjunction with the sensor  311  and/or the load port computer. 
       FIG. 4  illustrates a flow chart of a method of transferring semiconductor wafers between a transport pod and a semiconductor processing apparatus using a load port. In step  401 , the transport pod is placed on a pod transport plate of the load port. The transport pod may be aligned on the pod transport plate using a plurality of registration pins or the like. The transport pod may be held in position on the pod transport plate using a plurality of clamps. The transport pod may include a plurality of semiconductor wafers, or the semiconductor wafers may be disposed within the semiconductor processing apparatus. In step  403 , the pod transport plate is moved from a first position distal a load port door of the load port to a second position proximal the load port door. In step  405 , the transport pod is optionally purged. An inert gas, such as nitrogen gas or the like may be used to purge the transport pod. In step  407 , once the pod transport plate reaches the second position, a frame of the transport pod is sealed to the load port. In step  409 , the load port door and a transport pod door of the transport pod are opened, allowing access between the interior of the transport pod and a transfer module of the semiconductor processing apparatus. 
     In step  411 , semiconductor wafers are transferred between the transport pod and the transfer module. In some embodiments, the semiconductor wafers may be transferred from the transport pod to the transfer module. The semiconductor wafers may then be transferred between various chambers of the semiconductor processing apparatus and various semiconductor processing steps may be performed on the semiconductor wafers. In some embodiments, the load port door and the transport pod door may be closed after the semiconductor wafers are transferred to the transfer module, while the semiconductor processing steps are performed on the semiconductor wafers. Once the semiconductor processing steps are completed, the semiconductor wafers may be transferred back to the transport pod from the transfer module. In step  413 , the transport pod door and the load port door are closed. 
     In step  415 , the transport pod is optionally purged. The purge process may decrease humidity and oxygen in the transport pod, increasing Q-time. In step  417 , the pod transport plate is moved from the second position back to the first position. The transport pod is unclamped from the pod transport plate. In step  419 , the transport pod is removed from the pod transport plate. The transport pod may then be moved to other semiconductor processing apparatuses for additional processing. 
       FIGS. 5A and 5B  illustrate a front view and a back view of a sensor  311 . The sensor  311  may include an accelerometer  501 , indicator lights  503 , programmable buttons  505 , a reset button  507 , an edge connector  509 , a compass  513 , a processor  515 , an antenna  517 , a USB connector  519 , a battery socket  521 , and the like. The accelerometer  501  measures movement of the sensor  311  along three axes (e.g., an X-axis, a Y-axis, and a Z-axis) and can measure movement of the sensor  311  along any of the three axes, tilting of the sensor  311  in a latitudinal direction, and tilting of the sensor in a longitudinal direction. The accelerometer  501  may be used to determine a tilt angle of the sensor  311  between 0 and 90 degrees. The accelerometer  501  may also be used to determine the speed and frequency of any movement of the sensor  311  and may thereby be used to track any vibration of the sensor  311 . The processor  515  may be used to process data obtained by the accelerometer  501  and other sensors on the sensor  311 . 
     The indicator lights  503  may be used to display the direction and the severity of any unleveling or vibration of the sensor  311  detected by the sensor  311 . As such, the indicator lights  503  may be used to adjust the leveling of the load port by showing a user which direction the load port needs to be moved and illustrating when the load port is level. The indicator lights  503  may be LEDs or the like. The indicator lights  503  may be configured to display a warning if the unleveling or the vibration of the sensor  311  exceeds a threshold value. The sensor  311  may further include a speaker, which may also be programmed to sound a warning if the unleveling or the vibration of the sensor  311  exceeds the threshold value. In some embodiments, the sensor  311  may be connected to a laser, and may be programmed to control the laser to provide a warning if the unleveling or the vibration of the sensor  311  exceeds the threshold value. The programmable buttons  505  may be used to turn the sensor  311  on and off, to change between different modes, to set an initial position of the sensor  311 , or the like. For example, in one embodiment, the sensor  311  may be placed on the load port  301 , then the programmable buttons  505  may be used to set an initial position of the sensor  311 . The reset button  507  may reset the sensor  311 . 
     The edge connector  509  may include large pins, which are connected to holes  511  passing through the sensor  311 , and small pins. The large pins may be compatible with crocodile clips, banana plugs, and the like. In some embodiments, the edge connector may include about 5 large pins and about 20 small pins; however, any suitable number of pins may be included. The antenna  517  may be configured to communicate via radio, Bluetooth, and the like. For example, the antenna  517  may be configured to communicate with other sensors  311  by radio and with Bluetooth devices by Bluetooth. A battery (not separately illustrated) may be connected to the battery socket  521  to power the various components of the sensor  311 . The sensor  311  may also be powered through the edge connector  509  or the USB connector  519 . The edge connector  509 , the antenna  517 , and the USB connector  519  may be configured to provide communication between the processor and external devices, such as a load port computer, a cell phone, and the like. The edge connector  509 , the antenna  517 , and the USB connector  519  may be collectively referred to as communication modules. In an embodiment, the communication modules may be configured to provide data indicating the leveling and the vibration of the sensor  311  to the load port computer. The communication modules may be further configured to send a warning to a cell phone or the like if the unleveling or the vibration of the sensor  311  exceeds the threshold value. 
     In various embodiments, a load port computer may be configured to communicate with the sensor  311 . The load port computer may be connected to the sensor  311  using the USB connector  519 . The load port computer may be used to code and control the sensor  311  using a coding language such as Javascript, Python, Scratch, or the like. The load port computer may be provided with a graphical user interface (GUI) used to control the sensor  311 . 
     In some embodiments, data from the sensor  311  may be sent to a fault detection and classification device (not separately illustrated). The fault detection and classification device may transform data from the sensor  311  into summary statistics and models. The fault detection may analyze the statistics and models against defined limits and provide a warning if the leveling or the vibration of the sensor are outside of the defined limits. For example, if the leveling or vibration of the sensor  311  are outside of the defined limits, the fault detection and classification device may send out a phone call alert, produce an audible alarm, produce visual alarms, combinations thereof, or the like. 
       FIGS. 6A-6C  illustrate various configurations for the indicator lights  503  on the sensors  311 . As illustrated in  FIG. 6A , indicator lights  503 A may have a circular shape and may be arranged in a 5 by 5 square, and sensor  311 A may have a square shape. As illustrated in  FIG. 6B , indicator lights  503 B may have a rectangular shape and may be arranged in a 5 by 5 rectangle, and sensor  311 B may have an oval shape. As illustrated in  FIG. 5C , indicator lights  503 C may have a diamond shape and may be arranged in a cross with 7 indicator lights arranged along an X-axis and 7 indicator lights arranged along a Y-axis, and sensor  311 C may have a circular shape. Any other shape may be used for the indicator lights  503  and the sensor  311  and the indicator lights  503  may be arranged in any suitable shape. For example, the indicator lights  503  may have a circular shape, an oval shape, a square shape, a diamond shape, a rhomboid shape, or the like, and the indicator lights  503  may be points, lines, balls, or the like. The indicator lights  503  may be arranged in a square, a rectangle, a circle, an oval, a diamond, a cross, a T, a line, multiple lines, combinations thereof, or the like. The sensor  311  may have a circular shape, an oval shape, a square shape, a diamond shape, a rhomboid shape, or the like. Any number of indicator lights  503  may be included on the sensor  311 . For example, a number of indicator lights  503  arranged along an X-axis of the sensor  311  may range from 1 to 1,000 and a number of indicator lights  503  arranged along a Y-axis of the sensor  311  may range from about 1 to 1,000. The indicator lights  503  may each be separated from neighboring indicator lights  503  by a distance ranging from about 1 mm to about 100 mm. The indicator lights  503  may be arranged between about 1 mm and about 100 mm from side surfaces of the sensor  311 . The sensor  311  may have a length of less than about 100 mm or from about 1 mm to about 100 mm, such as about 42 mm; a width of less than about 100 mm or from about 1 mm to about 100 mm, such as about 52 mm; and a height of from about 6 mm to about 18 mm, such as about 12 mm. 
     The sensor  311  may be configured to detect leveling of the load port  301  in real time. As such, including the sensor  311  on the load port  301  helps to quickly detect any unleveling or excessive vibration of the load port  301  and provide warnings of such conditions. As such, the leveling of the load port  301  can be corrected quickly. Moreover, the sensor  311  may indicate the direction and severity of any unleveling of the load port  301 ; therefore, the sensor  311  may be used to correct the leveling of the load port  301 . Correcting unleveling and excessive vibration of the load port  301  helps to prevent defects in the semiconductor wafers, which may be caused by the excessive vibration, misalignment of the load port, exposure to contamination, and the like, and, thereby, helps to increase device yield. 
       FIG. 7  illustrates a block diagram of a load port computer  701  that may be used for implementing the previously described methods and embodiments, in accordance with a representative embodiment. In some embodiments, the load port computer may utilize all of the components shown, or only a subset of the components, and levels of integration may vary from embodiment to embodiment. Furthermore, the load port computer  701  may contain multiple instances of a component, such as multiple processing units, processors, memories, transmitters, receivers, etc. 
     The load port computer  701  may include a central processing unit (CPU)  703 , a storage device  705 , a network interface  707 , a memory  709 , a video adapter  711 , and an input/output (I/O) interface  713 . The CPU  703 , the storage device  705 , the network interface  707 , the memory  709 , the video adapter  711 , and the input/output interface  713  may be connected to a bus  715 . 
     The bus  715  may be one or more of any type of several bus architectures including a memory bus or memory controller, a peripheral bus, a video bus, or the like. The CPU  703  may include any type of electronic data processor. The memory  709  may include any type of system memory such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), read-only memory (ROM), a combination thereof, or the like. In an embodiment, the memory  709  may include ROM for use at boot-up, and DRAM for program and data storage for use while executing programs. 
     The storage device  705  may include any type of storage device configured to store data, programs, and other information and to make the data, programs, and other information accessible via the bus  715 . In various embodiments, the storage device  705  may include, for example, one or more of a solid state drive, a hard disk drive, a magnetic disk drive, an optical disk drive, or the like. 
     The video adapter  711  and the I/O interface  713  provide interfaces to couple external input and output devices to the load port computer  701 . In various embodiments, the input and output devices may include a display coupled to the video adapter  711  and a mouse, a keyboard, a speaker, a microphone, a touchscreen, a keypad, a printer, combinations thereof, or the like coupled to the I/O interface  713 . In various embodiments, the sensor  311  may be coupled to the I/O interface  713 . Other devices may be coupled to the load port computer  701  and additional or fewer interface cards may be utilized. For example, a serial interface card (not separately illustrated) may be used to provide a serial interface for a printer. 
     The load port computer  701  also includes a network interface  707 , which may comprise wired links, such as an Ethernet cable or the like, and/or wireless links to access nodes or different networks. The network interface  707  allows the load port computer  701  to communicate with remote units via the networks. For example, the network interface may provide wireless communication via one or more transmitters/transmit antennas and one or more receivers/receive antennas. In an embodiment, the processing unit is coupled to a local-area network or a wide-area network for data processing and communications with remote devices, such as other processing units, the Internet, remote storage facilities, or the like. In some embodiments, the load port computer  701  may be coupled to the sensor  311  wirelessly through the network interface  707 . 
     The load port computer  701  may be used in conjunction with the sensor  311  to level the load port  301 . For example, the sensor  311  may detect an acceleration of the load port using the accelerometer  501 . Either the sensor  311  or the load port computer  701  may determine a level measurement of the load port  301  based on the detected acceleration and determine whether the level measurement is within an allowance of level. The load port  301  may then be leveled if the level measurement is outside the allowance. 
     In accordance with an embodiment, a sensor includes an accelerometer configured to detect leveling and vibration of a load port and produce a plurality of data; a plurality of indicator lights configured to display a level measurement and a level direction based on the leveling of the load port; a processor configured to process the data produced by the accelerometer; and a wired connection configured to connect the processor to an external device. In an embodiment, the indicator lights are arranged in a cross pattern. In an embodiment, the wired connection includes a USB port. In an embodiment, the wired connection includes an edge connector. In an embodiment, the sensor further includes a plurality of programmable buttons configured to program the sensor. 
     In accordance with another embodiment, a load port includes a pod support configured to hold a semiconductor wafer transport pod; a load port door through which semiconductor wafers are transported; and a load port leveling sensor, the load port leveling sensor configured to measure the leveling of the load port, the load port leveling sensor including a plurality of indicator lights indicating the leveling of the load port, the load port leveling sensor being disposed directly on the pod support. In an embodiment, the pod support is configured to hold a semiconductor wafer transport pod on an uppermost surface thereof, and the load port leveling sensor is disposed on the uppermost surface of the pod support. In an embodiment, the pod support is configured to hold a semiconductor wafer transport pod on an uppermost surface thereof, and the load port leveling sensor is disposed on a side surface of the pod support. In an embodiment, the load port further includes a load port computer, the load port computer being connected to the load port leveling sensor, the load port computer being configured to receive feedback data from the load port leveling sensor indicating the leveling of the load port. In an embodiment, the load port computer is configured to communicate with the load port leveling sensor using Javascript. In an embodiment, the load port computer is connected to the load port leveling sensor using a wired connection. In an embodiment, the load port leveling sensor has a rectangular shape, and a length and a width of the load port leveling sensor are less than 100 mm. 
     In accordance with yet another embodiment, a method includes detecting an acceleration of a sensor on a load port using an accelerometer; determining a level measurement of the load port based on the detected acceleration; determining whether the level measurement is within an allowance of level; and leveling the load port if the level measurement is outside the allowance using indicator lights on the sensor as a guide. In an embodiment, the sensor determines the level measurement and determines whether the level measurement is within the allowance. In an embodiment, a computer external to the sensor determines the level measurement and determines whether the level measurement is within the allowance. In an embodiment, the method further includes automatically leveling the load port if the level measurement is outside the allowance using a leveling mechanism. In an embodiment, the method further includes determining a vibration of the load port based on the detected acceleration and leveling the load port if the calculated vibration is greater than a threshold value. In an embodiment, the method further includes sending feedback data from the sensor to a load port computer using a wired connection. In an embodiment, the method further includes sending a phone call alert if the level measurement is outside the tolerance. In an embodiment, the method further includes providing an auditory alarm if the level measurement is outside the tolerance. 
     The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.