semi合集-English.pdf - 第5048页
SEMI M18-0704 © SEMI 1990, 2004 34 NOTICE: SEMI makes no warranties or representations as to the su itability of the standard set fo rth herein for any particular application . The determinati on of the suitability o f t…
SEMI M18-0704 © SEMI 1990, 2004 33
Line Item EDI Code ID Sub Param ID
25.12 SOI Etch Pit 100238
25.13 Threading Dislocation 100239
25.14 HF Defect 100240
25.15 Void 100241
25.16 Roughness (Si surface)
rms @ 2 × 2µm
100242
Roughness (Si surface)
rms @ 10 × 10µm
100243
Roughness (Si surface)
rms @ [ ] × [ ]µm
100244
Roughness (Si surface)
rms @ [ ] × [ ]µm
100245
25.17 Surface Metal Contamination (Fe) 100246
Surface Metal Contamination (Cr) 100247
Surface Metal Contamination (Ni) 100248
Surface Metal Contamination (Cu) 100249
Surface Metal Contamination [ ] 100250
Surface Metal Contamination [ ] 100251
Surface Metal Contamination [ ] 100252
Surface Metal Contamination [ ] 100253
Surface Metal Contamination [ ] 100254
Surface Metal Contamination [ ] 100255
26.1 BOX Thickness 100256
26.2 BOX Thickness Variation 100267
26.3 Bonded Interface Location 100258
26.4 BOX Pinholes 100259
26.5 Dielectric Breakdown 100260
27.1 Warp 100261
27.2 Flatness-site 100262
28.1 Scratch 100263
28.2 Haze 100264
28.3 LLS
@particle size
100265
100266
28.4 Slip 100267
28.5 Edge Chip 100268
28.6 Edge Crack 100269
28.7 Foreign Matter 100270
29.1 Backside Metal Contamination (Fe) 100271
Backside Metal Contamination (Cr) 100272
Backside Metal Contamination (Ni) 100273
Backside Metal Contamination (Cu) 100274
Backside Metal Contamination [ ] 100275
Backside Metal Contamination [ ] 100276
Backside Metal Contamination [ ] 100277
Backside Metal Contamination [ ] 100278
Backside Metal Contamination [ ] 100279
Backside Metal Contamination [ ] 100280
SEMI M18-0704 © SEMI 1990, 2004 34
NOTICE: SEMI makes no warranties or representations as to the suitability of the standard set forth herein for any
particular application. The determination of the suitability of the standard is solely the responsibility of the user.
Users are cautioned to refer to manufacturer’s instructions, product labels, product data sheets, and other relevant
literature respecting any materials mentioned herein. These standards are subject to change without notice.
The user’s attention is called to the possibility that compliance with this standard may require use of copyrighted
material or of an invention covered by patent rights. By publication of this standard, SEMI takes no position
respecting the validity of any patent rights or copyrights asserted in connection with any item mentioned in this
standard. Users of this standard are expressly advised that determination of any such patent rights or copyrights, and
the risk of infringement of such rights, are entirely their own responsibility.
Copyright by SEMI® (Semiconductor Equipment and Materials
International), 3081 Zanker Road, San Jose, CA 95134. Reproduction o
f
the contents in whole or in part is forbidden without express written
consent of SEMI.
SEMI M19-91 © SEMI 1991, 19961
SEMI M19-91
SPECIFICATION FOR ELECTRICAL PROPERTIES OF BULK GALLIUM
ARSENIDE SINGLE CRYSTAL SUBSTRATES
1 Introduction
For the specification, three principal types of material
were identified: semi-insulating, n-type, and p-type.
This encompasses the full range of conductivity
characteristics for Gallium Arsenide (GaAs). Section 3
considers subclasses of these characteristics defining
the species which may be used for producing the
conductivity type. For semi-insulating material, special
cases have been isolated.
Undoped, Grade A1 represents those materials which
are of high resistivity and stable following growth,
without necessitating any additional annealing or
processing. The Grade A2 material, “high purity”,
requires additional thermal processing following
growth to bring the resistivity to a level > 10
7
Ω-cm. At
this time, most producers have indicated that the
majority of the Grade A2 ingots have resistivity
characteristics which rise into the acceptable range after
an appropriate thermal cycle. However, this
phenomenon is sensitive to the details of the time-
temperature cycle, and thus, such an increase cannot be
guaranteed in every application. Thus, the label “Grade
A2” is used to denote this material.
Chromium doping produces a high resistivity material.
However, due to the rapid diffusion of Cr during
processing and the propensity for surface accumulation,
it is not as well suited to processing as grades 3.A.1 and
3.A.2, thus we assign this material “grade A”.
Iso-electric dopant additions do not appear to affect the
resistivity significantly, but rather, permit the reduction
of dislocation generation in the final product. Thus, this
material is classified Grade A. While In is the most
effective hardening agent, Al, P, and Sb are also viable
species. They are included for completeness and to
reduce the likelihood of document revision at a later
date. The Grade B specification encompasses those
materials where the impurity and point defect densities
are not quite in the proper balance, but the resistivity is
suitable for less-stringent applications.
For conducting material, the best characterized, non-
transition metal species have been included as n-type
dopants; for p-type, a broader range of species has been
included, as transition metals are useful acceptor
impurities.
Section 4 defines the resistivity and stability of semi-
insulating material as specified in Section 3. A stringent
limit was placed on the Grade A2 material to minimize
the likelihood that this material converts to low
resistivity upon annealing. The issue of surface
conversion in Cr-doped material was dealt with by
eliminating a requirement for n-type characteristics
following annealing.
The resistivity ranges for n-type conducting material
were determined from the carrier concentration table
(Section 5) and mobility values, using the analysis of
Walukiewicz et al, J. Appl. Phys. 50 (1979) 899. This
places a constraint on the permissible compensation
ratio, selected to be in the range of approximately 0.0 to
0.7. The specification was designed then to exclude
abnormally poor crystals. As limited data and demand
exist for p-type material, there are no ranges specified
at this writing. Should a significant body of data evolve,
this specification may be designed and balloted as
appropriate.
Section 5 deals with impurity concentrations, net
electron yields and implicitly, with point defect
concentrations. For semi-insulating material of high
quality, the impurities are, at the present time, not
reliably measurable (carbon is the notable exception).
Thus the “unspecified” nomenclature. For types A-3
and A-4, the determination of the amount of the
relevant impurity species is given to the appropriate
party, the user, and producer, respectively.
For n-type materials, the ranges were selected to define
a high purity regime (n ≤ 4 × 10
16
cm
-3
), an intermediate
regime where donor density is not more than ~10 times
the typical deep level density; the transition region
wherein deep levels are suppressed (range B-3); a
highly doped range (> 10 ppm net electron
concentration yield); and “saturation” doping range
where the crystal growth process and thermodynamics
determine the limits of impurity incorporation and
electron yield.
In Section 6, the electron mobility values and ranges are
stated. For semi-insulating materials, the values that
have been determined by consensus are 5000 cm
2
/V-s
for Grade A1 and 6000 cm
2
/V-s. In the interest of
harmony, and to prevent further debilitating
discussions, the authors and participants at the SEMI
meetings, and responses from producers have been used
to set this value at 5000 cm
2
/V-s. The producers
indicated that the Grade A2 material nearly always
exceeds 6000 cm
2
/V-s, and thus this value was adopted.
For chromium doped materials, the mobility is less
predictable and, therefore, is negotiated between the
user and producer. In-doped materials have consistently
lower mobilities, resulting from strain-effects,