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Example 002

Question:

Identify the packaging schemes of the following types of commercial devices.  Identify the scheme for both circuit-mechanical integration and for encapsulation.

* InvenSense gyro (ITG-3200) (Link)

* STMicroelectronics gyro L3G4200 D (Link)

* Texas Instrument digital micro mirror (DMD)

Answer:

  Circuit-mechanical integration Encapsulation
ITG 3200 (Link to review) circuits and mechanical elements are contained on two chips, but placed in one package.(Fig. 1 below) Vacuum wafer bonding, Nasiri process. (Fig. 2) 
L3G4200D (Link to Chipworks review) Circuit and mechanical elements are bonded together to form a single chip; (see Fig. 2 below). vacuum wafer bonding encapsulation
Texas Instruments DLP Monolithic integration, mechanical on top of MOS electronics; low temperature process and materials for mechanical parts (Al as mirror and photoresist as sacrificial wafer) (see Fig. 4 below) package level vacuum encapsulation (see Fig. 5 below)

Fig. 1: Side view of ITG3200.

Fig. 2: The Nasiri process for making ITG3200.

Fig. 3: L3G4200D chip

Fig. 4: Scanning electronics micrograph of TI DLP Chip.

Fig. 5. A picture of the TI DLP package.