List of contributors ....................................... xiv
Preface ..................................................... xv
1 Silicon LDMOS and VDMOS transistors: physics, design, and
technology ................................................... 1
Wayne Burger and Christopher P. Dragon
1.1 Technology overview ..................................... 1
1.1.1 Introduction/history ............................. 1
1.2 LDMOS and VDMOS construction ............................ 2
1.2.1 LDMOS ............................................ 2
1.2.2 VDMOS ............................................ 8
1.3 Device physics ......................................... 10
1.3.1 Current transport ............................... 10
1.3.2 Behavior of parasitic elements/models ........... 12
1.3.3 ВVDSS, RDson, HCI boundaries .................... 17
1.3.4 Snapback/ruggedness ............................. 22
1.3.5 Operating voltage considerations ................ 26
1.4 Design/layout .......................................... 27
1.4.1 Top-down finger layout .......................... 27
1.4.2 Bond pad manifolds .............................. 29
1.4.3 Metal design - electromigration ................. 30
1.4.4 Thermal ......................................... 32
1.4.5 Operating voltage considerations ................ 34
1.4.6 Frequency considerations: gate length, gate
width, resistors ................................ 36
1.4.7 HVICs ........................................... 37
References ............................................. 39
2 GaAs FETs - physics, design, and models ..................... 42
Rob Davis
2.1 Introduction ........................................... 42
2.1.1 Properties of GaAs and related compounds ........ 43
2.1.2 The Schottky barrier gate and the MESFET ........ 45
2.1.3 The Pƒ2 limit ................................... 45
2.1.4 Types of GaAs FET ............................... 46
2.2 Power device physics ................................... 51
2.2.1 The device I-V characteristic and loadline ...... 51
2.2.2 The dynamic I-Vcharacteristic ................... 53
2.2.3 The consequences of trapping effects ............ 54
2.2.4 Device breakdown ................................ 57
2.2.5 Breakdown mechanisms and optimisation ........... 58
2.2.6 Comments on GaAs FET breakdown ratings .......... 59
2.2.7 The FET equivalent circuit ...................... 60
2.2.8 Device gain and figures of merit ................ 61
2.3 Device design .......................................... 63
2.3.1 Power device design ............................. 63
2.3.2 FET channel and recess design ................... 63
2.3.3 Power cell design ............................... 67
2.3.4 Power cell combination .......................... 71
2.3.5 Thermal design .................................. 72
2.4 Device fabrication ..................................... 74
2.4.1 Overview ........................................ 74
2.4.2 Key process steps ............................... 75
2.4.3 Low-cost GaAs device fabrication ................ 81
2.4.4 Packaging ....................................... 81
2.5 Models ................................................. 84
2.5.1 Device models ................................... 84
2.5.2 Small-signal models ............................. 84
2.5.3 Large signal models ............................. 85
2.5.4 Load-pull ....................................... 89
2.6 Concluding remarks ..................................... 90
References ............................................. 91
3 Wide band gap transistors - SiC and GaN - physics,
design and models .......................................... 103
Robert J. Trew
3.1 Introduction .......................................... 103
3.2 Background ............................................ 105
3.2.1 SiC transistors ................................ 106
3.2.2 AlGaN/GaN transistors .......................... 108
3.3 Material parameters ................................... 111
3.4 Transistor amplifier operating principles ............. 115
3.5 Device design and RF performance ...................... 118
3.5.1 4H-SiC MESFET amplifier ........................ 120
3.5.2 AlGaN/GaN HFET amplifier ....................... 123
3.6 Transistor DC and large-signal RF models .............. 125
3.6.1 Equivalent circuit transistor models ........... 125
3.6.2 Physics-based large-signal transistor models ... 128
3.7 Large-signal effects .................................. 130
3.7.1 Space charge limited current transport ......... 130
3.7.2 Nonlinear source and drain resistance .......... 133
3.7.3 Gate leakage ................................... 144
3.7.4 Reliability and time-dependent performance
degradation .................................... 146
3.8 Summary ............................................... 152
References ................................................. 153
4 Amplifier classes, A-S ..................................... 159
Steve C. Cripps
4.1 Introduction .......................................... 159
4.2 Active device models .................................. 161
4.3 Class A ............................................... 162
4.4 Class AB and Class В .................................. 164
4.5 Class С ............................................... 171
4.6 Class F ............................................... 173
4.7 Class J ............................................... 176
4.8 Inverted modes, inverted Class F ...................... 179
4.9 Class E ............................................... 181
4.10 Class S ............................................... 183
4.11 Multimodes ............................................ 184
4.12 Conclusions ........................................... 186
References ................................................. 186
5 Computer-aided design of power amplifiers .................. 188
Stephen Maas
5.1 Introduction ........................................... 188
5.2 Methods of analysis ................................... 188
5.2.1 Linear analysis ................................ 188
5.2.2 Harmonic-balance analysis ...................... 193
5.2.3 Time-domain analysis ........................... 202
5.2.4 Applications of analytical methods ............. 205
5.3 Passive circuit structures and simulation accuracy .... 205
5.3.1 Scattering parameter models .................... 206
5.3.2 Closed-form models ............................. 208
5.3.3 Models from EM simulation ...................... 210
5.3.4 Database models ................................ 212
5.3.5 Parasitic extraction ........................... 212
5.4 Solid-state device models ............................. 213
5.4.1 Power device models ............................ 213
5.4.2 Modeling cell interconnections in large
devices ........................................ 213
5.4.3 Thermal effects in device models ............... 214
5.5 Special aspects of power-amplifier modeling ........... 216
5.5.1 Loss in circuit metalizations .................. 217
5.5.2 Loss in circuit components ..................... 219
5.5.3 Bond wires ..................................... 219
5.6 Practical aspects of nonlinear circuit simulation ..... 221
5.6.1 Convergence difficulties ....................... 221
5.6.2 SPICE models in harmonic-balance analysis ...... 226
5.6.3 Problem size minimization and solution
optimization ................................... 226
5.6.4 Numerical considerations ....................... 227
5.6.5 Design flow .................................... 228
References ................................................. 230
6 Practical HF/VHF/UHF RF power amplifier realization ........ 232
Daniel P. Myer
6.1 Introduction .......................................... 232
6.2 RF power amplifier markets ............................ 232
6.3 The realization process ............................... 233
6.3.1 RFPA qualitative specification delineation ..... 234
6.3.2 RFPA specifications, generic list and
quantification guidelines ...................... 236
6.3.3 Specification/hardware realization ............. 241
6.4 RFPA system level design overview ..................... 242
6.4.1 RF power amplifier module design overview ...... 243
6.4.2 RF power transistor device selection process
guidelines ..................................... 246
6.4.3 RF power transistor bias/thermal tracking
networks ....................................... 249
6.4.4 RF input/output coupling/decoupling networks ... 250
6.4.5 Power transistor impedance matching ............ 250
6.4.6 Feedback networks .............................. 251
6.4.7 Thermal management ............................. 251
6.5 Hypothetical amplifier design example ................. 252
6.5.1 Hypothetical application example overview ...... 252
6.5.2 Amplifier qualitative specification
delineation .................................... 252
6.5.3 Amplifier specification quantification ......... 253
6.5.4 Amplifier hardware design/realization .......... 254
6.6.1 RF transistor selection ........................ 255
6.5.1 Gate bias/temperature tracking/compensation
network ........................................ 257
6.5.2 Input/output RF/DC coupling/decoupling
networks ....................................... 259
6.5.3 Input/output impedance matching networks ....... 259
6.5.4 Feedback network ............................... 267
6.5.5 Test setup configuration/analysis .............. 268
6.5.6 Physical RFPA module construction .............. 271
6.5.7 RFPA module test results ....................... 273
6.5.8 Beyond the test data ........................... 281
References ................................................. 283
7 Microwave hybrid amplifier realization ..................... 284
Dominic FitzPatrick
7.1 Introduction .......................................... 284
7.2 Printed circuit boards ................................ 285
7.3 Housing ............................................... 293
7.3.1 Materials ...................................... 294
7.3.2 Sealing and hermeticity ........................ 294
7.3.3 Construction ................................... 299
7.3.4 Thermal issues and heat sinking ................ 305
7.3.5 RF connections ................................. 311
7.4 Components ............................................ 315
7.4.1 Passive - lumped components .................... 315
7.4.2 Passive - distributed components ............... 323
7.4.3 Transistors .................................... 331
7.5 Amplifier design ...................................... 333
7.5.1 Topologies ..................................... 333
7.5.2 Matching and stability ......................... 336
7.5.3 Internally matched device amplifiers ........... 343
7.5.4 Combining ...................................... 344
7.5.5 Module size/system integration ................. 344
7.6 Biasing and control ................................... 345
7.6.1 Control and interfacing ........................ 352
7.7 Tuning techniques ..................................... 353
References ................................................. 355
8 Monolithic power amplifiers ................................ 357
Inder J. Bahl
8.1 Overview of MMIC power amplifiers ..................... 357
8.1.1 Brief history of MMIC power amplifiers ......... 357
8.1.2 Advantages of monolithic power amplifiers ...... 358
8.2 Monolithic 1С technology .............................. 359
8.2.1 MMIC fabrication ............................... 360
8.2.2 MMIC substrates ................................ 361
8.2.3 MMIC active devices ............................ 361
8.2.4 MMIC matching elements ......................... 362
8.3 MMIC design methodology ............................... 370
8.3.1 CAD tools ...................................... 370
8.3.2 Design procedure ............................... 371
8.3.3 EM simulators .................................. 372
8.4 MMIC PA summary and examples .......................... 372
8.4.1 Narrowband power amplifier ..................... 374
8.4.2 Broadband power amplifiers ..................... 376
8.4.3 Ultra broadband power amplifiers ............... 377
8.4.4 High-power amplifiers .......................... 381
8.4.5 Millimeter-wave 2.4W PA ........................ 386
8.4.6 Wireless 3W power amplifier .................... 386
8.4.7 High-voltage monolithic PAs .................... 387
8.5 Packaging of MMIC PAs ................................. 389
8.5.1 Ceramic packages ............................... 390
8.5.2 Plastic packages ............................... 394
8.5.3 Package assembly ............................... 396
8.6 MMIC power amplifier characterization ................. 401
References ................................................. 406
9 RF power amplifier thermal design .......................... 411
Mali Mahalingam
9.1 Why thermal design deserves careful attention? ........ 411
9.2 RFPA thermal design - basics .......................... 413
9.2.1 RFPA thermal design in a typical portable
product ........................................ 413
9.2.2 RFPA thermal design in a typical radio base
station ........................................ 416
9.2.3 Basic heat transfer processes and their role
in an RFPA thermal performance ................. 419
9.3 Thermo-physical properties of materials in an RFPA .... 423
9.4 Tools to characterize and predict the thermal
performance of RFPAs .................................. 427
9.5 RFPA thermal design and management - advanced ......... 432
9.6 RFPA thermal design - trends and prognostication ...... 440
References ................................................. 442
10 Reliability ................................................ 446
Bill Roesch
10.1 Introduction .......................................... 446
10.2 Vocabulary and definitions (units, goals, and
strategy) ............................................. 447
10.2.1 Reliability goals .............................. 448
10.2.2 Semiconductor reliability strategy ............. 448
10.3 Failure criteria ...................................... 449
10.4 Failure modes ......................................... 450
10.5 Failure mechanisms .................................... 451
10.5.1 Metalization ................................... 451
10.5.2 Dielectric ..................................... 453
10.5.3 Bulk substrate material ........................ 454
10.5.4 Schottky gate FET failure causes ............... 454
10.6 Failure distributions ................................. 455
10.7 Acceleration factors .................................. 458
10.7.1 Thermal acceleration ........................... 458
10.7.2 Current acceleration ........................... 462
10.7.3 Voltage acceleration factors ................... 465
10.7.4 RF bias acceleration ........................... 472
10.8 Reliability predictions (MTBF, MTTF, FITs, etc.) ...... 473
10.9 Wear-out versus defects (acceleration versus real
life) ................................................. 475
10.9.1 Thermal excursion example no. 1. Interconnect
vias ........................................... 475
10.9.2 Thermal excursion example no. 2. Copper bump ... 478
10.9.3 Defect amplification and К factors ............. 482
10.9.4 Environmental example - humidity activation
energy ......................................... 488
10.10 Process effects and influence ........................ 492
10.11 Design for reliability ............................... 495
10.12 Historical trends and technology comparisons ......... 501
10.13 Summary .............................................. 502
References ................................................. 505
11 Power amplifier applications ............................... 508
Mustafa Akkul and Wolfgang Bösch
11.1 Introduction .......................................... 508
11.2 System design parameter tradeoffs ..................... 509
11.2.1 Output power-efficiency tradeoff ............... 509
11.2.2 Linearity, modulation scheme, and crest
factor ......................................... 512
11.3 System level linearization techniques ................. 514
11.3.1 Introduction to linearization techniques ....... 514
11.3.2 Digital baseband predistortion ................. 514
11.3.3 Memory effect compensation ..................... 517
11.3.4 Impact on power efficiency ..................... 517
11.4 Wireless communication power amplifiers ............... 519
11.4.1 Mobile radio communication today ............... 519
11.4.2 System level and power amplifier
requirements ................................... 522
11.4.3 Power amplifier design outline ................. 523
11.4.4 Doherty amplifier for efficient base stations .. 527
11.5 Military power amplifiers ............................. 530
11.5.1 Radar Tx/Rx modules ............................ 530
11.5.2 EW applications ................................ 534
11.5.3 Anti-IED applications .......................... 538
11.6 In-phase power combining techniques ................... 538
11.6.1 Wilkinson power combiners ...................... 538
11.6.2 Gysel combiner ................................. 542
11.7 Quadrature-phase power combining - balanced
amplifiers ............................................ 544
11.7.1 Branch-line quadrature hybrid [19] ............. 547
11.7.2 Lange coupler .................................. 549
11.8 Anti-phase power combining - push-pull amplifiers ..... 552
11.8.1 Coupled coil transformers ...................... 553
11.8.2 Transmission line transformers ................. 554
11.8.3 RF/microwave push-pull amplifier ............... 557
11.9 Doherty combining ..................................... 559
11.10 Conclusions .......................................... 567
References ................................................. 568
12 Amplifier measurements ..................................... 570
Michael G. Hiebel
12.1 Introduction .......................................... 570
12.2 Power measurements .................................... 570
12.2.1 Typical power sensor principles ................ 570
12.2.2 Typical sources of measurement uncertainties ... 574
12.2.3 High-power RF measurements and directional
power .......................................... 576
12.2.4 Power measurements using a spectrum analyzer ... 579
12.3 S-parameter measurements .............................. 580
12.3.1 The concept of S-parameters .................... 580
12.3.2 Scalar network analyzers and their
limitations .................................... 582
12.3.3 Vector network analyzers ....................... 586
12.3.4 Introduction to system error correction ........ 588
12.3.5 Calibration with different connector types ..... 589
12.3.6 Calibration with PCBs, test fixtures, and
wafer probers .................................. 593
12.3.7 Calibration consideration for high-power
setups ......................................... 596
12.3.8 Residual errors and measurement uncertainties .. 598
12.4 Further linear measurements ........................... 599
12.4.1 Amplifier gain definitions ..................... 599
12.4.2 Efficiency factor .............................. 602
12.4.3 Linear distortion, phase and group delay
measurement .................................... 603
12.4.4 Linear stability considerations ................ 605
12.4.5 Mixed-mode S-parameters ........................ 608
12.5 Nonlinear measurements ................................ 611
12.5.1 Inter modulation distortion (IMD) and
harmonic distortion (HMD) ...................... 611
12.5.2 Compression point .............................. 615
12.5.3 Large-signal network analysis .................. 616
12.5.4 Load- and source-pull measurements ............. 619
12.5.5 Hot 5-parameters ............................... 622
12.6 Modulated measurements ................................ 623
12.6.1 Crest factor and CCDF .......................... 624
12.6.2 Adjacent channel power ratio (ACPR) ............ 625
12.6.3 Noise-power ratio (NPR) ........................ 630
12.6.4 Error vector magnitude (EVM) and
constellation diagram .......................... 630
12.6.5 AM/AM and AM/PM measurements ................... 632
12.6.6 Memory effects ................................. 632
12.6.7 Pulsed measurements ............................ 633
12.6.8 Bit error ratio (BER) and symbol error ratio
(SER) .......................................... 635
12.7 Noise measurements .................................... 636
12.7.1 Amplifier noise factor and noise figure ........ 637
12.7.2 Noise figure measurement ....................... 637
12.7.3 Noise parameters ............................... 640
12.8 Conclusions ........................................... 641
References ................................................. 642
About the authors .......................................... 644
Index ...................................................... 651
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