On - Wafer 3 - port S - parameter Calibration October 1997

Preface The objective of the present work is to establish methods for dealing with on-wafer 3-port S-parameter measurements. Error correction methods including calibration and deembedding 1 are discussed and verified experimentally. Chapter 1 presents two basically different methods for making 3-port S-parameter measurements using a 2-port network analyzer. The methods are termed the renormalization and the iterative method. Both methods require three sets of 2-port S-parameters and additional 1-port S-parameter measurements to calculate the wanted set of 3-port S-parameters. Also, a method for deembedding measured 3-port S-parameters denoted renormalization is presented. Chapter 2 presents and discusses commonly used 2-port calibration methods which can be used together with the presented method for 3-port measurements. Chapter 3 discusses on-wafer issues, i.e. which measurement difficulties exist, and what can be done to overcome these problems. Also, accuracy enhancements are suggested. Implementations and specifications of two calibration kits (SOLT and TRL) are presented in Chapter 4. In Chapter 5 a general conclusion is drawn to give an overall impression of the results obtained. All experiments use devices build of a 0.5µm GaAs process (F20), supplied by GEC-Marconi [GEC]. In the present work the F20 design manual from GEC-Marconi is frequently used, but this material is not avail-1 Deembedding is the process of removing effects from embedding circuits. able to others, as it is only made available to the author through a confidential agreement. Unfortunately this means that fabrication spread and other figure of merits can not be stated in the present work, even when used as the basis of choices and in analyses. All chips are manufactured by support of EUROPRACTICE 2 , a project supported by the European Commission (EC). The aim of EUROPRAC-TICE is to stimulate European industry to a " wider application of state-of-the-art microelectronics technologies ". Several different services are available from EUROPRACTICE of which the Multi-Project Wafer (MPW) prototyping service is used in the present work. By letting several customers sharing fabrication costs to a wafer, the costs are reduced. Customers are industry as well as academic institutions. The price per square millimeter chip area for the GEC F20 process is currently 480 ECU for educational use only, whereas industry must pay 795 ECU per square millimeter. In danish kroners DKK this correspond to approximately DKK 3,580 and DKK 5,930, respectively. Also, note that the effective area of e.g. a 2x2mm 2 chip is only 1.785x1.785mm 2 due the …