Title :
Modular integration of CMOS and SOI-MEMS using "plug-up" concept
Author :
Kiihamaki, J. ; Ronkainen, H. ; Pekko, Panu ; Kattelus, H. ; Theqvist, K.
Author_Institution :
Microelectron., VTT Inf. Technol., FI, Finland
Abstract :
This paper reports a novel method for monolithic integration of electronics with micromechanical devices. The fabrication sequence differs from those previously described. Even though some of the elements of CMOS and MEMS fabrication are intermixed and make use of each other, they still are modular packages, which can be sequentially fabricated in separate specialized factories if both of the technologies are not available at one site. Standard or tailored SOI wafers can be used for the substrate material. Vacuum cavities are then made at predetermined regions of the buried oxide using a special technique, "Plug-up". We have demonstrated that cavity wafers of this kind can progress through the entire bipolar enhanced CMOS cycle without complications. In the end, MOS and bipolar transistors operate almost identically to reference devices on bulk silicon wafers and MEMS membranes resonate mechanically as anticipated. The proposed modular process sequence is tabulated in Fig. 1.
Keywords :
CMOS integrated circuits; MOSFET; bipolar transistors; elemental semiconductors; micromechanical devices; monolithic integrated circuits; silicon; silicon-on-insulator; MEMS membranes; MOS transistors; SOI-MEMS; Si; bipolar enhanced CMOS; bipolar transistors; bulk silicon wafers; cavity wafers; micromechanical devices; modular integration; monolithic integration; Biomembranes; Bipolar transistors; CMOS technology; Electronics packaging; Fabrication; Micromechanical devices; Monolithic integrated circuits; Production facilities; Silicon; Vacuum technology;
Conference_Titel :
TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7731-1
DOI :
10.1109/SENSOR.2003.1217098