Over the past few years integrated microsystems have sparked off a deluge of innovative ideas in the microelectronics industry. The tiny all-round devices packed into the smallest of spaces can detect and process electrical, optical, acoustic or mechanical information, for example, and convert these into suitable control commands. Standard handling machines for testing ICs have been around for some time now, yet these are only capable of testing electrical microsystem functions. The great versatility of these microsystems, however, calls for a completely new approach with regard to the functionality of test handlers.
The main feature of Leonardo is its ability to enable full tests - both electrical and physical - to be performed on microsystems. This is done by standardized transportation of microsystems into and out of a product-specific test area.
Components to be tested (DUTs) can be loaded in trays, tubes or in-line. The loading system can cope with devices of up to 100 mm in height, enabling larger components or even entire systems to be transported. Two parallel conveyor belts with adjustable width permit devices to be separated off after testing, so that components which have failed a test run can be removed from the production line.
A pick-and-place robot equipped with either vacuum pick-up tools or pneumatic or electrical grippers is used to transfer all types of package to the test station. The position of the DUT can be measured en route to the test station using an alignment camera, enabling precise placement (+/- 50 µm) in the test socket.
At 700 x 550 x 950 mm (W x L x H) the test area is generous in size, providing the flexibility and adaptability needed to cater for the testing of the variety of microsystems now on the market. Leonardo provides the necessary supply terminals (low voltages, compressed air, vacuum) and programmable inputs and outputs which can also be read or switched while the DUT is being transported. This allows preparatory measures to be carried out at the test station, such as the opening and closing of the test socket, for example. With the aid of cameras the DUT can be brought into a predefined position once it has been placed in the test socket.
Leonardo can handle two test stations simultaneously which, depending on the duration of the test, can drastically reduce the effective transportation time and thus increase the throughput. While a DUT is being tested at one station, the other station can be emptied and reloaded.
The multilingual graphic user interface permits intuitive operation of the machine while allowing maximum freedom with configuration. The product-specific parameters and modules are stored in a customized project file, the possible number of which is unlimited.
The software package also includes automatic recognition of the installed modules plus system security guaranteed by three different user levels and a password-protected logon procedure.
An external tester can be connected either in binary via a TTL interface, serially via RS232 or via an Ethernet link (TCP/IP).
Results from the tester can be saved in an ASCII file or in a customized database. Leonardo comes with an uninterruptible power supply (UPS). Current results are therefore not lost but stored before the program is closed.
A label dispenser for marking the tested components is also available. This can work with up to eight different labels for the binning of components. Leonardo's modular concept also permits the customized integration of other marking systems and methods.