3. Photomicrographs of typical tungsten carbide probe tips 10 10 2. Ratio of spreading resistance, Rsp, to resistivity, p, as a function of 4. 5. 6. 1. 8. 9. 10. 11. 12. 13. Resistivity as a function of temperature for seven phosphorus-doped silicon slices Resistivity of phosphorus-doped silicon at 300 K as a function of total donor density . Thermally controlled chuck and automatic wafer prober Thermally stimulated current response of gold-doped n-MOS capacitor with an Capacitance-voltage characteristics of various oxides on n-type silicon with aluminum gate electrodes . . 14. Capacitance-voltage characteristics of four MOS capacitors on each of four 25 26 LIST OF FIGURES PAGE 15. 16. Specular reflection data for four bulk silicon substrates polished with different polishing grits and for six silicon-on-sapphire composites Scanning electron micrographs of silicon-on-sapphire surfaces. 17. Schematic of experimental conditions for ion sputter etching and Auger electron spectroscopy . 19. Additional broadening of an interface at a depth of 100 nm due to flux inhomogeneity in rastered ion beams of normal and defective ion guns Oxygen KLL profiles showing effects of electron-beam enhancement of sputtering rate . . 33 21. Geometry for crater-edge profiling using Auger electron spectroscopy 22. 34 Line scans for oxygen, phosphorus, and elemental silicon across the interface between the points C and C1 on the x-axis 23. Sodium density in the atmosphere of a fused silica oxidation tube as a function of water vapor content at temperatures from 1200 to 1400 K 35 37 24. 25. 26. Total ionizing dose deposited in the oxide layer as a function of electron- 27. Absorbance of x-ray energy in nylon film dosimeter as a function of the electron charge incident on aluminum in an e-gun evaporator 28. Typical target configuration for characterizing the ion beam before ion implantation . Target current densities as a function of scanner voltage for an 84-keV boron ion beam 31. 32. Schematic representation of corona charging with positive ions Schematic representation of the reverse decoration of defects with negative ions following corona charging with positive ions 33. Photomicrograph of reverse decorated device showing high contrast which renders microscopic evaluation fast and sensitive . 34. Photomicrograph of portion of reverse decorated device aluminum-etched at 50°C for 5 min without removing carbon black Schematic representation of microscope modified to obtain image of source field stop at the photocell to measure the integrated light reflected from defective areas . 36. Sketch of the single-lens coherent optical system, showing the locations of various planes and coordinate systems . . 38. 37. Calculated images of clear lines in opaque backgrounds for coherent illumination of wavelength 500 nm, and a 0.95 numerical aperture objective lens Sketch of a possible configuration for a microscope system with spatial filtering 39. Diagram of optical research microscope as modified for line-width measurement LIST OF FIGURES 40. 41. Calculated and experimentally determined line-image profiles for clear lines in opaque backgrounds . . . Photomicrograph of chromium-on-glass artifact, viewed under bright-field transmitted light at a magnification of about 85x . . . PACE 52 53 42. Photomicrograph of four 1-um wide clear spaces each separated by 1 um in 53 43. 44. Schematic representation of optical system for diffraction pattern analysis Arrangement of a square four-probe array on the diagonals of a thin, square specimen 63 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. Normalized sheet resistance error resulting from shorting contacts on the periphery of a square test structure Normalized sheet resistance error resulting from shorting contacts at the ends of the arms of a Greek cross test structure Distribution of p-channel saturation current in heavy inversion along the Apparatus for applying upward or downward force on beam-lead devices and Acoustic emission signals from individual beams subjected to downward force on the horizontal portion of the beam . . Beam-lead bonding tool modified to apply force to the beams without contacting the chip. Typical signatures of ultrasonic aluminum-aluminum wire bonds made with different power settings... Photoresponse of a typical 2N4431 UHF transistor to 0.633- and 1.15-um radiation as a function of temperature . Temperature profile of hot spots in typical 2N4431 UHF transistors as measured with a laser scanner and an infrared microradiometer Photograph of the reflected light plus photoresponse image obtained when the 0.633-μm laser beam scans the back side of a silicon-on-sapphire C-MOS 4007 inverter Photograph of the reflected light image obtained when the 1.15-um laser beam scans the back side of a flip-chip C-MOS 4007 inverter . . Photographs of the reflected light plus photoresponse image obtained when the 1.15-um laser beam scans the back side of a flip-chip 709 operational amplifier 63. Comparison of operating modes of the scanning acoustic microscope . 64. 65. Acoustic images showing differences between cw and pulsed operation. Comparison between 940-MHz acoustic images of a bipolar microwave transistor with 2-um wide metal fingers and a photomicrograph taken with interference contrast .. LIST OF FIGURES PAGE Frequency dependence of attenuation of acoustic waves in water at various temperatures Acoustic images, reflection mode at 940 MHz, of an integrated circuit showing the effect of non-normal incidence Frequency response of return and transmission loss of two sputtered glass acoustic anti-reflection coatings (AARC). Change in threshold voltage, AVTh, of a p-channel MOS transistor as the result of exposure to an electron flux of 5.2 x 1010 cm-2.s-1 at energies of 17.5 and 30 keV in a scanning electron microscope Electron-beam-induced-current response of a copper-doped silicon p-n diode Portion of a quad 2-input NAND gate including a functional gate on the left Portions of a low-power, four-bit shift register LIST OF TABLES Results of Four-Probe Pilot Study on Thin Layers Equilibrium Partial Pressures and Sodium Densities in Fused Silica Oxidation Apparent Widths of Lines and Spaces Measured in Bright-Field Transmitted Effect of Focal Position on the Apparent Width of a Clear Space Measured with an Image-Shearing Eyepiece in Bright-Field Transmitted Illumination Apparent Widths of Clear Lines in an Opaque Field . Representative Data for Line-Width Measurements Repeated on the Same Line Representative Response Frequencies of Metal Spheres Impacting a Steel PREFACE The Semiconductor Technology Program serves to focus NBS efforts to enhance the performance, interchangeability, and reliability of discrete semiconductor devices and integrated circuits through improvements in measurement technology for use in specifying materials and devices in national and international commerce and for use by industry in controlling device fabrication processes. Its major thrusts are the development of carefully evaluated and well documented test procedures and associated technology and the dissemination of such information to the electronics community. Application of the output by industry will contribute to higher yields, lower cost, and higher reliability of semiconductor devices. The output provides a common basis for the purchase specifications of government agencies which will lead to greater economy in government procurement. In addition, improved measurement technology will provide a basis for controlled improvements in fabrication processes and in essential device characteristics. The The Program receives direct financial support principally from two major sponsors: the Defense Advanced Research Projects Agency (ARPA)* and the National Bureau of Standards (NBS).† In addition, the Program receives support from the Defense Nuclear Agency (DNA), the Air Force Space and Missiles Systems Organization, the Navy Strategic # Systems Project Office, and the Energy Research and Development Administration.* ARPA-supported portion of the Program, Advancement of Reliability, Processing, and Automation for Integrated Circuits with the National Bureau of Standards (ARPA/IC/NBS), addresses critical Defense Department problems in the yield, reliability, and availability of digital monolithic integrated circuits. Other portions of the Program emphasize aspects of the work which relate to the specific needs of the supporting agency. Measurement oriented activity appropriate to the mission of NBS is an essential aspect in all parts of the Program. Essential assistance to the Program is also received from the semiconductor industry through cooperative experiments and technical exchanges. NBS interacts with industrial users and suppliers of semiconductor devices through participation in standardizing organizations; through direct consultations with device and material suppliers, government agencies, and other users; and through periodically scheduled symposia and workshops. In addition, progress reports, such as this one, are regularly prepared for issuance in the NBS Special Publication 400 sub-series. More detailed reports such as state-of-the-art reviews, literature compilations, and summaries of technical efforts conducted within the Program are issued as these activities are completed. Reports of this type which are published by NBS also appear in the Special Publication 400- sub-series. Announcements of availability of all publications in this subseries are sent by the Government Printing Office to those who have requested this service. A request form for this purpose may be found at the end of this report. Another means of interaction with the electronics community is by direct contact. In particular, comments from readers regarding the usefulness of the results reported herein or relating to directions of future activity in the Program are always welcome. Disclaimer Certain commercially available materials or instruments are identified in this publication for the purpose of providing a complete description of the work performed. The experiments reported do not constitute a complete evaluation of the performance characteristics of the products so identified. In no case does such identification imply recommendation or endorsement by the National Bureau of Standards nor does it imply that the items identified are necessarily the best available for the purpose. * Through ARPA Order 2397, Program Code 6D10 (NBS Cost Center 4257555). All contract work was funded from this source. + Principally through the Electronic Technology Program (Cost Center 4257100). Additional funding through the Dimensional Metrology Program (Cost Center 2131119) and the Nondestructive Evaluation Program (Cost Center 4253130). § Through Inter-Agency Cost Reimbursement Order 76-806 (NBS Cost Center 4259522). ¶ Through MIPR FY76 167600366 (NBS Cost Center 4259560). # Code SP-23, through project order N0016475P070030 administered by Naval Weapons Support Center, Crane, Indiana (NBS Cost Center 4251533). × Division of Electric Energy Systems, through ERDA Contract No. E(49-1)-3300, Modification 3 (NBS Cost Center 4259561). |