IMPLANT

During an IMPLANT step, the statistics from the library are used to calculate the PearsonIV impurity profile of the implanted ELEMENT. If the range, standard deviation or higher moments of the desired impurity distribution are specified, these values overwrite the library values used to calculate the profile. The user can also specify an exponentially decaying tail, which begins either at BEGINTAIL or the position where the concentration is half the peak value, to account for the effects of channeling.

• ELEMENT=(s)
• DOSE=(r)
• ENERGY=(r)
• [RANGE=(r)]
• [SIGMA=(r)]
• [LAT.SIGMA=(r)]
• [SKEWNESS=(r)]
• [KURTOSIS=(r)]
• [TAIL=(r)]
• [BEGINTAIL=(r)]
• [TILT=(r)]
• [FILE=(s)]
• [DSCALE=(r)]
• [PLUSFACTOR=(r)]

The following list itemizes the valid keywords, their units, and their meaning:

ELEMENT: [string]

impurity element to be implanted. Possible values are found in the library in library/physics/implant.

DOSE: [real ( )]

dose of the implant. The dose may be trimmed using the command dbase create library/physics/silicon/boron/tom.factor rval=0.83 taking boron as an example. This will modify the boron dose to 83% of the nominal value in every subsequent implant.

ENERGY: [real (keV)]

energy of the implant.

TILT: [real (degrees)]

tilt of the beam. The model assumes no rotation, only tilt.

RANGE: [real (microns)]

range of the distribution.

SIGMA: [real (microns)]

vertical standard deviation of the distribution.

LAT.SIGMA: [real (microns)]

lateral standard deviation of the distribution.

SKEWNESS: [real]

of the profile (3rd moment).

KURTOSIS: [real]

of the profile (4th moment).

TAIL: [real (microns)]

characteristic length for the exponential tail of the profile.

BEGINTAIL: [real (microns)]

distance from the surface where the tail of the profile should begin. Default is where the concentration of the implant reaches half the maximum.

FILE: [string]

name of the file from which the 1D implant statistics is read in. The file must have two columns, separated by tabs or blank characters. The first column should give the depth in microns, and the second column the concentration in . For a 2D simulation, by default the lateral sigma is set to equal the vertical sigma value which is extracted from the 1D implant statistics given by the file. The user can also set a value for the lateral sigma using the "lat.sigma" option.

DSCALE: [real]

scaling factor to apply to a profile read from file. Default value is 1.0. Caution: does not apply to profiles specified with dose and energy, only profiles from file.

PLUSFACTOR: [real]

the implant code to implant a number of interstitials equal in distribution to the implanted species, and with dose equal to that of the implanted species multiplied by PLUSFACTOR. The implanted dose should not exceed the amorphization threshold of silicon; attempts to do so will be rejected.

Examples:
implant energy=30 dose=1.e16 elem=arsenic
implant element=boron energy=100 dose=1e15 lat.sigma=.021
implant element=arsenic file=my_arsenic lat.sigma=0.1

where file "my_arsenic" is of the form:

 
0.010  		3.0e20

0.012  		3.1e20

0.0135 		3.3e20

Less Used IMPLANT Keywords

CONCENTRATION

resulting from implant. Either DOSE or CONCENTRATION may be specified, but not both.

COLUMN.IMSIL

implant data from IMSIL.

CMODEL

keyword. Should be removed.