ABSTRACT
CMP and Its Application Process ............................ 350 7.2 Basic Concept of Planarization CMP ................................................ 354
Toshiro K. Doi
7.2.1 Basics of CMP-Progress of Ultraprecision Polishing and Its Applications ................................................................ 356
7.2.2 Requirements and Points to Be Noted for Planarization CMP .................................................................. 357
7.2.3 Basic Design Concept of CMP System.................................. 359 7.2.4 Works to Be Polished by CMP and Defects Caused
by Polishing ............................................................................ 359 7.3 Basic Technology of Planarization CMP........................................... 363
7.3.1 CMP Machine System ............................................................ 363
Toshiro K. Doi
7.3.1.1 Polishing Station....................................................... 365 7.3.1.2 Cleaning Station ....................................................... 369
7.3.2 Slurries for CMP..................................................................... 370
Masaharu Kinoshita
7.3.2.1 Basis of CMP Slurries .............................................. 370 7.3.2.2 ILD CMP Slurry....................................................... 371 7.3.2.3 STI CMP Slurry........................................................ 373 7.3.2.4 W-CMP Slurry.......................................................... 381 7.3.2.5 Cu CMP Slurry......................................................... 386
7.3.3 Pads for Planarization CMP ................................................... 396
Masanobu Hanazono and Masaharu Kinoshita
7.3.3.1 Basic Properties of the CMP Polishing Pad ............ 396 7.3.3.2 Pad Conditioning and Polishing Performance ......... 404 7.3.3.3 Improvement for New Pads ..................................... 411
7.3.4 Modeling and Simulation of CMP Processes......................... 414
Masaharu Kinoshita
7.3.4.1 Purpose of Modeling ................................................ 414 7.3.4.2 Modeling of Planarization Process .......................... 415 7.3.4.3 Modeling of the Polishing Pad
and Planarization ...................................................... 424 7.3.4.4 Modeling of Slurry Behavior ................................... 431
7.4 The Study Case of Device Wafer ...................................................... 436
Keisuke Suzuki
7.4.1 Introduction of CMP Technology .......................................... 437 7.4.2 History of CMP Technology .................................................. 439 7.4.3 Device Integration and CMP .................................................. 443
7.4.3.1 Device Fabrication ................................................... 443 7.4.3.2 Problems in Integration ............................................ 444
7.4.4 Present State of the CMP Development................................. 449 7.4.4.1 STI-CMP.................................................................. 449 7.4.4.2 Tungsten CMP.......................................................... 452 7.4.4.3 Cu and Low-k CMP ................................................. 452
7.4.5 Development of Endpoint Detection Method ........................ 458 7.4.6 Future Prospects...................................................................... 459
7.5 Thin Film Magnetic Recording Heads............................................... 460
Masanobu Hanazono
7.5.1 Structure and Read and Write Mechanism of Thin Film Magnetic Head ............................................................... 460
7.5.2 CMP Process for Thin Film Magnetic Heads ........................ 463 7.5.2.1 Smoothing of Alumina Basecoat
Film Surface ............................................................. 463 7.5.2.2 Bottom Shield CMP ................................................. 464 7.5.2.3 Bottom Pole and Top Shield CMP .......................... 465 7.5.2.4 Cu Damascene Process............................................. 466 7.5.2.5 Overcoat CMP .......................................................... 467
7.6 CMP of Compound Semiconductor Wafers ...................................... 468
Toshiro K. Doi
7.6.1 Polishing Characteristics of GaAs Crystal Wafers ................ 469 7.6.2 Polishing Characteristics of CdTe Crystal Wafers ................ 471
References.................................................................................................... 473
Taking a general view of the development of ultralarge-scale integration
(ULSI) devices, the background that requires chemical mechanical polishing
(CMP) as a processing method of multilevel interconnections and planariza-
tion is clarified. Requirements for CMP, system construction method, and key
element technologies are discussed here while reviewing the latest trends of
ULSI devices and the needs of planarization CMP with its process. Moreover,
case examples of the actual planarization CMP of device wafers are intro-
duced here, referring also to the application cases to other fields.