Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Method and System for Extracting Different Elements Present in a Silicon-on-Insulator (SOI) Substrate

IP.com Disclosure Number: IPCOM000201540D
Publication Date: 2010-Nov-15
Document File: 4 page(s) / 187K

Publishing Venue

The IP.com Prior Art Database

Abstract

A method and system for extracting different elements present in a Silicon-on-Insulator (SOI) substrate is disclosed.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 51% of the total text.

Page 01 of 4

Method and System for Extracting Different Elements Present in a Silicon -on-Insulator (SOI) Substrate

Disclosed is a method and system for extracting different elements present in a Silicon-on-Insulator (SOI) substrate is disclosed.

SOI substrates are generally used for the Radio Frequency (RF) front end in cellular applications. Modeling of an SOI substrate is a challenge due to high resistivity in the SOI substrate and imperfections present in Si/SiO2 interface.

Fig. 1 illustrates a cross section of various elements present in an SOI substrate. Depending on the type of the SOI substrate used, active regions in the SOI substrate can be extracted using Shallow Trench Isolation (STI) in case of a thin film SOI substrate or by using deep Trench Isolation (TI) in case of a thick film SOI. The extracted islands of active regions are formed by STI or TI touching the Buried Oxide (BOX). The cross section shown in Fig. 1 is for a thick film SOI. The main substrate elements which play a role in the circuit applications are the lateral components above the BOX, the BOX capacitance (Cbox) and substrate models below the BOX, namely Csxw and Rsxw.

(This page contains 00 pictures or other non-text object)

Figure 1

To extract lateral capacitance above the BOX, a ring structure as shown in Fig. 2 is used. The lateral component of the coupling is enhanced since the well is enclosed by isolation on all the sides. Also, the ratio of vertical coupling to lateral coupling which is also the ratio of area of the well to the perimeter is reduced.

1


Page 02 of 4

(This page contains 00 pictures or other non-text object)

Figure 2

Four such ring structures are defined in the SOI substrate having different widths, lengths and number of fingers. Thereafter, a global optimization routine provides an equation for the lateral component of the SOI substrate. The lateral component which is the lateral TI capacitanc...