Title :
A post processing method for reducing substrate coupling in mixed-signal integrated circuits
Author :
Basedau, Philipp ; Huang, Qiuting
Author_Institution :
Integrated Syst. Lab., Swiss Federal Inst. of Technol., Zurich, Switzerland
Abstract :
Due to the heavily doped substrate material in modern MOS technologies, digital interference couples to sensitive analog nodes much more easily than in technologies with p/sup -/ substrates. The guard ring method of isolating sensitive nodes is no longer as effective as before. In this contribution we investigate the isolation of analog circuits by etching a gap between analog and digital circuits from the back of the wafer. Experiments show that interference coupling 35 dB above noise floor is completely removed when a gap is etched around the analog circuit.
Keywords :
MOS integrated circuits; etching; integrated circuit noise; integrated circuit technology; mixed analogue-digital integrated circuits; MOS technologies; digital interference; etching; heavily doped substrate material; interference coupling; mixed-signal integrated circuits; noise floor; sensitive analog nodes; substrate coupling; Analog circuits; CMOS technology; Circuit noise; Coupling circuits; Digital circuits; Integrated circuit technology; Isolation technology; Mixed analog digital integrated circuits; RLC circuits; Silicon on insulator technology;
Conference_Titel :
VLSI Circuits, 1995. Digest of Technical Papers., 1995 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
0-7800-2599-0
DOI :
10.1109/VLSIC.1995.520679
