Reliability Engineering in Rf Cmos

Dit proefschrift is goedgekeurd door de promotoren: Summary 125 Samenvatting 127 List of publications 129 Dankwoord 131 Chapter 1 Introduction 1.1 RF CMOS The use of mobile wireless communication systems is rapidly increasing. Electronics involved in these systems are typically referred to as RF electronics. RF stands for radio frequencies, a term covering all frequencies of the electromagnetic spectrum used for transmitting radio signals. It spans from a few Hz to 100's of GHz. When dealing with present-day mobile applications the frequencies involved typically range between ∼500 MHz and ∼ 5 GHz. For example the four frequency bands used for GSM communication throughout the world are located around 850, 900, 1800 and 1900 MHz. In electronics design the term RF is often used to describe only those frequencies at which design and measurement issues start to arise that are typical for the high frequencies used in mobile wireless communication systems. Throughout this thesis the term RF also reflects only these high frequencies; in chapter 2 the precise definition of RF as used in this thesis will be explained. The IC technologies involved in wireless systems operating at such high frequencies include GaAs, SiGe, Bipolar, BiCMOS and CMOS. In earlier years CMOS was not applicable for RF electronics, but through the efforts made in scaling CMOS technology, the RF performance of CMOS has increased significantly [1]. As a consequence CMOS has become the dominating technology used for mobile wireless applications, like it has already dominated logic applications, such as CPU's, for decades. When used in RF electronics, CMOS is often referred to as RF CMOS. The only part of mobile applications in which CMOS still does not dominate is the Power Amplifier (PA). This module is used in the transmitting end of a wireless communication system. In the PA an electromagnetic wave is generated carrying all information, such as speech or data, which is fed to an antenna. The information this wave carries must be read at the receiver end, such as the base-station of a GSM network, of the wireless communication system. For the information to be available at the receiver end, the power of this electromagnetic 1 2 1 Introduction