semi合集-English.pdf - 第7340页

SEMI MF1389-0704 © 2004 8 NOTICE: SEMI makes no warranties or representations as to the suitability o f the standards set forth herei n for any pa rticular application. The determination of the suitability o f the standa…

at the minimum near 8840 cm

−1

. For the TO region

impurity lines, draw a line from (b) to (c) or (d): the

minimum near 8785 cm

−1

or 8768 cm

−1

, whichever is

lower.

12.2 Measure peak heights or areas. Use TO lines for B

and P. Use NP lines for Al and As. If the P

(BE) is

not usable, also use NP lines for P.

See Figure 4 for

identification of bands in the NP region.

12.3 Correct for the P

′) line underlying the

(BE) line by subtracting one-tenth of the intensity

of the P

(BE) line from the B

(BE) line intensity.

13 Calculation

13.1 Calculate the ratio of the extrinsic line intensity to

the I

(FE) line intensity for each impurity present.

13.2 Using the adjusted calibration curves obtained in

Section 10.1.3 find the point on the calibration curve

corresponding to the ratio (or log of the ratio, as

appropriate) obtained in Section 13.1 by graphical or

numerical methods.

13.3 Record the corresponding value of dopant density

in atoms/cm

14 Report

14.1 Report the following each time the instrument is

calibrated using primary or secondary standard

samples:

14.1.1 Standard sample ratios obtained in Section

10.1.2, and

14.1.2 Square Root of Mean Square, (RMS) precision

data obtained in Section 10.2.3

14.2 Report the following each time a load of samples

is run:

14.2.1 Audit specimen dopant density results,

14.2.2 Unknown ample dopant density results,

14.2.3 Sample lot number, number of samples, operator

name, and date of analysis, and

14.2.4 Test Method used (A or B).

15 Precision

15.1 A single laboratory investigation of the precision

of measurement of phosphorus and boron by photolu-

minescence was conducted on a Fourier transform

instrument. Two samples were analyzed once a day

12 Tajima, M., Masui, T., Itoh, D., and Nishino, T.,“ Calibration of

the Photoluminescence Method for Determining As and Al

Concentrations in Si,” Journal of Electrochemical Society, Vol 137,

1990, pp. 3544–3551.

over a period of several weeks (45 measurement values

were taken on each sample). The first sample contained

a nominal 70 ppta phosphorus and a nominal 30 ppta

boron; and the second sample contained a nominal 20

ppta phosphorus and a nominal 15 ppta boron. From

this multiple-day, two-operator, two-sample investiga-

tion, values of single laboratory standard deviation and

relative standard deviation based on the average

measured value were obtained and are tabulated in

Table 3.

Table 3 Standard Deviation Values for a Single

Laboratory Study of Variation of

Photoluminescence Measurements of Phosphorus

and Boron

Sample Dopant 1s, ppta R1s, percent

1 Phosphorus 2.43 3.4

1 Boron 1.69 6.2

2 Phosphorus 1.13 5.6

2 Boron 1.00 7.0

16 Bias

16.1 The bias of this test method cannot be evaluated

because there are no available reference standards

suitable for evaluating bias.

17 Keywords

17.1 aluminum; arsenic; boron; dopant; impurities;

impurity analysis; phosphorus; photoluminescence;

silicon.

NOTICE: SEMI makes no warranties or

representations as to the suitability of the standards 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 or equipment mentioned

herein. These standards are subject to change without

notice.

By publication of this standard, Semiconductor

Equipment and Materials International (SEMI) takes no

position respecting the validity of any patent rights or

copyrights asserted in connection with any items

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.

International), 3081 Zanker Road, San Jose, CA 95134. Reproduction o

the contents in whole or in part is forbidden without express written

consent of SEMI.

SEMI MF1390-1104 © SEMI 2004 1

SEMI MF1390-1104

TEST METHOD FOR MEASURING WARP ON SILICON WAFERS BY

AUTOMATED NON-CONTACT SCANNING

This test method was technically approved by the Global Silicon Wafer Committee and is the direct

responsibility of the North American Silicon Wafer Committee. Current edition approved for publication by

the North American Regional Standards Committee on August 16, 2004. Initially available at

www.semi.org

September 2004; to be published November 2004. Original edition published by ASTM International as

ASTM F 1390-92. Last previous edition SEMI MF1390-0704.

1 Purpose

1.1 Warp can significantly affect the yield of

semiconductor device processing.

1.2 Knowledge of this characteristic can help the

producer and consumer determine if the dimensional

characteristics of a specimen wafer satisfy given

geometrical requirements.

1.3 Changes in wafer warp during processing can

adversely affect subsequent handling and processing

steps. These changes can also provide an important

process monitoring function.

1.4 This test method is suitable for measuring the warp

of wafers used in semiconductor device processing in

the as-sliced, lapped, etched, polished, epitaxial or other

layer condition and for monitoring thermal and

mechanical effects on the warp of wafers during device

processing.

2 Scope

2.1 This test method covers a non-contacting,

nondestructive procedure to determine the warp of

clean, dry semiconductor wafers.

2.2 This test method employs a two-probe system that

examines both external surfaces of the wafer

simultaneously.

2.3 The test method is applicable to wafers 50 mm or

larger in diameter, and approximately 100 m and

larger in thickness, independent of thickness variation

and surface finish, and of gravitationally induced wafer

distortion.

2.4 This test method is not intended to measure the

flatness of either exposed silicon surface. Warp is a

measure of the distortion of the median surface of the

wafer.

2.5 This test method measures warp of a wafer

corrected for mechanical forces applied during the test.

Therefore, the procedure described gives the

unconstrained value of warp.

NOTE 1: This warp is indicated by the acronym

“GMLYMER” in Appendix 2, Shape Decision Tree, of SEMI

M1.

NOTE 2: SEMI MF657 measures median surface warp using

a three-point back-surface reference plane. The back-surface

reference results in thickness variation being included in the

recorded warp value. The use (in this test method) of a

median surface reference plane eliminates this effect. The use

(in this test method) of a least-squares fit reference plane

reduces the variability introduced in three-point plane

calculations by choice of reference point location. The use (in

this test method) of special calibration or compensating

techniques minimizes the effects of gravity-induced distortion

of the wafer.

2.6 This test method includes several methods for

canceling gravity-induced deflection which could

otherwise alter the shape of the wafer.

NOTE 3: One of these methods, the Representative Wafer

Inversion Method, is covered by a patent held by ADE

Corporation, 80 Wilson Way, Westwood, MA 02090-1806.

NOTICE: This standard does not purport to address

safety issues, if any, associated with its use. It is the

responsibility of the user of this standard to establish

appropriate safety and health practices and determine

the applicability of regulatory or other limitations prior

to use.

3 Limitations

3.1 Any relative motion along the probe measuring axis

between the probes and the wafer holding device during

scanning will produce error in the measurement data.

Vibration of the test specimen relative to the probe-

measuring axis will introduce error. Such errors are

minimized by system signature analysis and correction

algorithms. Internal system monitoring may also be

used to correct non-repetitive and repetitive system

mechanical translations. Failure to provide such

corrections may cause errors.

3.2 If a measured wafer differs substantially in

diameter, thickness, fiducials, or crystal orientation

from that used for the gravitational compensation

procedure, the results may be incorrect. Estimates of

the errors in gravity induced deflection for differences

1 Poduje, N., “Eliminating Gravitational Effect in Wafer Shape

Measurements,” NIST/ASTM/SEMI/SEMATECH Technology Confe-

rence, Dallas, TX. Technology for Advanced Materials/Process

Characterization, February 1, 1990.