Abstract:
A data collector control system for semiconductor manufacturing comprises a data collector and a automatic communication port switch control circuit. The control system is placed between an equipment and an equipment automation programming (EAP) system. The data collector processes and transmits communication messages between the equipment and the EAP system while the data collector operates normally. The communication messages between the equipment and the EAP system are transmitted through the control circuit instead of the data collector while the data collector operates abnormally.

Description:
[0001]    This application is a continuation application of and claims priority to application Ser. No. 11/433,448, filed May 15, 2006, and the disclosure of which is incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    (A) Field of the Invention 
         [0003]    The present invention is related to a data collector control system, and more specifically to a data collector control system with an automatic communication port switch. 
         [0004]    (B) Description of the Related Art 
         [0005]      FIG. 1  illustrates a schematic diagram of an equipment automation system for semiconductor manufacturing. A data collector  102  is placed between an equipment  101  and an equipment automation programming (EAP) system  103 . When the software or hardware of the data collector  102  is out of order, or power of the data collector is unexpectedly shut down, communication between the equipment  101  and the EAP system  103  is interrupted because the data collector  102  cannot switch its transmission path. Therefore, error rates of equipment automation increase, and yield rates of semiconductor products decrease. 
       SUMMARY OF THE INVENTION 
       [0006]    The objective of the present invention is to provide a data collector control system with an automatic communication port switch, so as to keep signals between an equipment and an equipment automation programming (EAP) system from disconnecting when a data collector is out of order or an unexpected power-off occurs. 
         [0007]    The data collector control system of the present invention is placed between the equipment and the EAP system and comprises a data collector and an automatic communication port switch control circuit. The data collector can be an industrial personal computer (IPC) and comprises a main board and a data collector program thereon. The data collector program is used for managing communication messages between the equipment and the EAP system. The automatic communication port switch control circuit comprises a first communication port, a second communication port, an active IC, a passive IC and a switch control circuit. The switch control circuit comprises a half wave rectification circuit, a delay circuit, a first relay and a second relay. The half wave rectification circuit, the delay circuit, the second relay and the first relay connect in order. 
         [0008]    The switch control circuit selects the active IC as a transmission path of communication messages between the equipment and the EAP system while the data collector operates normally. The communication messages can be sent from the equipment to the first communication port, then through the active IC to the main board of the data collector and be processed by the data collector program. Subsequently, the communication messages are sent to the EAP system through the second communication port. The communication messages can also be sent from the EAP system to the second communication port, then to the main board of the data collector and be processed by the data collector program. Subsequently, the communication messages are sent to the active IC and then to the equipment through the first communication port. 
         [0009]    The switch control circuit selects the passive IC as a transmission path of communication messages between the equipment and the EAP system when the software or hardware of the data collector is out of order. In other words, the transmission path of communication messages between the equipment and the EAP system bypasses the main board of the data collector when the data collector operates abnormally, and this prevents the communication between the equipment and the EAP system from disconnecting. 
         [0010]    The automatic communication port switch control circuit further comprises a normal LED indicator, an abnormal LED indicator and a status switch. The status switch comprises a normal position and an abnormal position, which are used for selecting operation modes of the data collector. The communication status between the equipment and the EAP system can be tested by switching the status switch to the abnormal position. When the communication status test is finished, the status switch is moved to the normal position. The normal LED indicator and abnormal LED indicator are used for indicating the status of the data collector control system. 
         [0011]    The automatic communication port switch control circuit further comprises a third relay with two switches. When power of the data collector is unexpectedly shut down during normal operation, common points of the two switches are connected from the normal open point to the normal close point simultaneously such that the equipment and the EAP system are connected through the third relay. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0012]      FIG. 1  illustrates a known schematic diagram of an equipment automation system for semiconductor manufacturing; 
           [0013]      FIG. 2(   a ) shows a block diagram of a data collector control system with an automatic communication port switch in accordance with one embodiment of the present invention; 
           [0014]      FIG. 2(   b ) shows detail components and circuits regarding the data collector control system of the present invention; 
           [0015]      FIG. 2(   c ) shows detail circuit operations of the first relay and the second relay of the present invention; and 
           [0016]      FIG. 2(   d ) shows a detail circuit operation of the third relay of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]      FIG. 2(   a ) shows a block diagram of a data collector control system  20  with automatic communication port switch in accordance with one embodiment of the present invention. The data collector control system  20  comprises a data collector  290  and an automatic communication port switch automatic communication port switch control circuit  200 . The data collector  290  can be an industrial personal computer (IPC) and comprises a main board  291  which can perform a data collector program  295 . The data collector program  295  is used for managing communication messages between an equipment  230  and an EAP system  240 . The automatic communication port switch control circuit  200  for automatic communication ports switching comprises a first communication port  201   a , a second communication port  201   b , an active IC  202 , a passive IC  203  and a switch control circuit  210 . The automatic communication port switch control circuit  200  connects the equipment  230  and the EAP system  240  through the first communication port  201   a  and the second communication port  201   b , respectively. The first communication port  201   a  and the second communication port  201   b  are both serial ports. 
         [0018]    The main board  291  comprises serial ports  291   a ,  291   b , and  291   c . The active IC  202  is placed between the serial port  291   a  and the first communication port  201   a . The serial port  291   b  connects the second communication port  201   b , whereas the serial port  291   c  connects the switch control circuit  210 . All serial ports mentioned above can be implemented by a data interface RS232. 
         [0019]    The switch control circuit  210  selects the active IC  202  as a transmission path of communication messages between the equipment  230  and the EAP system  240  when the data collector  290  operates normally. The communication messages can be sent from the equipment  230  to the first communication port  201   a , then through the active IC  202  to the main board  291  of the data collector  290 . Then the communication messages are processed by the data collector program  295  and subsequently are sent to the EAP system  240  through the second communication port  201   b . The communication messages can also be sent from the EAP system  240  to the second communication port  201   b , then to the main board  291 . Then the communication messages are processed by the data collector program  295  and subsequently are sent to the active IC  202 . Then the communication messages are sent to the equipment  230  through the first communication port  201   a.    
         [0020]    Once the software or hardware of the data collector  290  is out of order, the switch control circuit  210  enables the passive IC  203 . The communication messages can be sent from the equipment  230  to the first communication port  201   a , then to the passive IC  203 . Then the communication messages are sent to the EAP system  240  through the second communication port  201   b.    
         [0021]      FIG. 2(   b ) shows detail components and circuits regarding the data collector control system  20 . In addition, the automatic communication port switch control circuit  200  further comprises a third relay  205 , a normal LED indicator  206 , an abnormal LED indicator  207  and a status switch  208 . The normal LED indicator  206  and abnormal LED indicator  207  are used for indicating the status of the data collector control system  20 . The status switch  208  comprises a normal position and an abnormal position, which are used for selecting operation modes of the data collector  290 . The communication status between the equipment  230  and the EAP system  240  can be tested by moving the status switch  208  to the abnormal position. When the communication status test is finished, the status switch  208  is switched to the normal position. 
         [0022]    The switch control circuit  210  comprises a half wave rectification circuit  211 , a delay circuit  212 , a first relay  214  and a second relay  213 . The half wave rectification circuit  211 , the delay circuit  212 , the second relay  213  and the first relay  214  connect in order. 
         [0023]      FIG. 2(   c ) shows detail circuit operations of the first relay  214  and the second relay  213 . Each of the first relay  214  and the second relay  213  comprises a switch, two input points  2  and  3 , a common point  1 , a normal close point  4 , a normal open point  5  and an input point  3  connected to ground. The common point  1  of the second relay  213  is connected to the output end of the delay circuit  212 , the input point  2  of the second relay  213  is connected to the normal position of the status switch  208 . The common point  1  of the first relay  214  is connected to a 5V power supply, the input point  2  of the first relay  214  is connected to the normal close point  4  of the second relay  213 . The normal close point  4  of the first relay  214  is connected to the passive IC  203 , and the normal open point  5  of the first relay  214  is connected to the active IC  202 . 
         [0024]      FIG. 2(   d ) shows a detail circuit operation of the third relay  205 . The third relay  205  comprises two switches  205   a  and  205   b . The switches  205   a  and  205   b  switch simultaneously such that the equipment  230  and the EAP system  240  are connected through the third relay  205  when power of the data collector system  20  is unexpectedly shut down. 
         [0025]    A periodic control signal with −10V to +10V voltage is generated by the data collector program  295  and is outputted from the serial port  291   c  of the main board  291  to the half wave rectification circuit  211 . After the negative voltage has been filtered out by the half wave rectification circuit  211 , then delayed by the delay circuit  212 , a 10V control signal is generated and inputted to the common point  1  of the second relay  213 . 
         [0026]    Once the software or hardware of the data collector  290  is out of order, a −10V control signal is generated by the data collector program  295  and is outputted from the serial port  291   c  of the main board  291  to the half wave rectification circuit  211 . After the negative voltage has been filtered out by the half wave rectification circuit  211 , then delayed by the delay circuit  212 , a 0V control signal is generated and inputted to the common point  1  of the second relay  213 . 
         [0027]    The anode of the normal LED indicator  206  is connected to the abnormal position of the status switch  208 . The normal LED indicator  206  is off when the status switch  208  is in the abnormal position, whereas the normal LED indicator  206  is on when the status switch  208  is in the normal position. The anode of the abnormal LED indicator  207  is connected to the normal close point  4  of the first relay  214 , and the status (on or off) of the abnormal LED indicator  207  is determined by the voltage level of the normal close point  4  of the first relay  214 . 
         [0028]    Operation cases of the data collector control system  20  can be classified in the following 7 cases. 
         [0029]    Case 1: In the beginning, the data collector program  295  has not yet started, the status switch  208  is in the abnormal position, the abnormal LED indicator  207  is on and the normal LED indicator  206  is off. After starting and running the data collector program  295  for a period of time, the status switch  208  is switched to the normal position and the normal LED indicator  206  turns on. Simultaneously, the input voltage of the input point  2  of the second relay  213  drops from 5V to 0V, the common point  1  of the second relay  213  is connected to the normal close point  4  such that the input voltage of the input point  2  of the first relay  214  rises from 0V to 10V. Subsequently, the common point  1  of the first relay  214  is connected from the normal close point  4  to the normal open point  5 , the abnormal LED indicator  207  turns off and the active IC  202  starts operating. 
         [0030]    Case 2: In the beginning, the data collector program  295  has not yet started, the status switch  208  is in the normal position, the common point  1  of the second relay  213  is connected to the normal close point  4 , and the abnormal LED indicator  207  and the normal LED indicator  206  are on. After starting and running the data collector program  295  for a period of time, a 10V signal is generated by the delay circuit  212 . As the common point  1  of the second relay  213  is connected to the normal close point  4 , the input voltage of the input point  2  of the first relay  214  rises from 0V to 10V. Subsequently, the common point  1  of the first relay  214  is connected from the normal close point  4  to the normal open point  5 , the abnormal LED indicator  207  turns off and the active IC  202  starts operating. 
         [0031]    Case 3: In the beginning, the data collector  290  operates normally, the status switch  208  is in the normal position, the common point  1  of the second relay  213  is connected to the normal close point  4 , the abnormal LED indicator  207  is off and the normal LED indicator  206  is on. After the operating system (OS) of the main board  291  or the data collector program  295  crashes, or the hardware of the data collector system  20  is out of order, the output signal of the delay circuit  212  drops from 10V to 0V for a period of time and the input voltage of the input point  2  of the first relay  214  drops from 10V to 0V. Subsequently, the common point  1  of the first relay  214  is connected from the normal open point  5  to the normal close point  4 , the abnormal LED indicator  207  turns on and the passive IC  202  starts operating. 
         [0032]    Case 4: The status switch  208  is switched from the normal position to the abnormal position to test communication status between the equipment  230  and the EAP system  240  when the data collector  290  operates normally. Then the normal LED indicator  206  turns off immediately and the input voltage of the input point  2  of the second relay  213  rises from 0V to 5V, the common point  1  of the second relay  213  is connected from the normal close point  4  to the normal close point  5  such that the input voltage of the input point  2  of the second relay  214  drops from 10V to 0V. Subsequently, the common point  1  of the first relay  214  is connected from the normal open point  5  to the normal close point  4 , and the abnormal LED indicator  207  turns on and the passive IC  203  starts operating. 
         [0033]    Case 5: When the power of the data collector system  20  is not yet turned on or is unexpectedly shut down, referring to  FIG. 2(   d ), the common points  1  of the switches  205   a  and  205   b  of the third relay  205  are connected to the normal close point  4  simultaneously such that the equipment  230  and the EAP system  240  are connected through the third relay  205 . 
         [0034]    Case 6: When the power of the data collector system  20  is turned on, the common points  1  of the switches  205   a  and  205   b  of the third relay  205  are connected from the normal close point  4  to the normal open point  5  simultaneously so as to break the connection between the equipment  230  and the EAP system  240  through the third relay  205 . 
         [0035]    Case 7: If the power of the data collector  290  is unexpectedly shut down while the data collector  290  operates normally, then the common points  1  of the switches  205   a  and  205   b  of the third relay  205  are connected from the normal open point  5  to the normal close point  4  simultaneously such that the equipment  230  and the EAP system  240  are connected through the third relay  205 . 
         [0036]    As mentioned above, the switch control circuit  210  selects the passive IC  203  as a transmission path of communication messages between the equipment  230  and the EAP system  240  when the software or hardware of the data collector  290  is out of order, or if power of the data collector is unexpectedly shut down. In other words, the transmission path of communication messages between the equipment  230  and the EAP system  240  bypasses the main board  291  of the data collector  290  when the data collector  290  operates abnormally, and this prevents communication between the equipment  230  and the EAP system  240  from disconnecting. 
         [0037]    The above-described embodiments of the present invention are intended to be illustrative only. Numerous alternative embodiments may be devised by those skilled in the art without departing from the scope of the following claims.