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In the following we will discuss details of the most commonly used commands in the SDF and JDF and provide example files for various types of jobs. We will start with a simple exposure without pattern alignment, i.e. a first print exposure. In JEOL terminology this is called “mask exposure mode” whereas exposure with alignment is refered to as “direct exposure mode”.
In the following we will discuss details of the most commonly used commands in the SDF and JDF and provide example files for various types of jobs. We will start with a simple exposure without pattern alignment, i.e. a first print exposure. In JEOL terminology this is called “mask exposure mode” whereas exposure with alignment is refered to as “direct exposure mode”.
Templates for SDF and JDF files can be found on the Cleanroom drive here: O:\CleanroomDrive\_JEOL9500Training\Templates


=First print - mask exposure mode=
=First print - mask exposure mode=
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ACC 100                       
ACC 100                       
CALPRM '2na_ap4'             
CALPRM '2na_ap4'             
DEFMODE 2                    
DEFMODE 2  
FFOCUS                   
RESIST 240                     
RESIST 240                     
SHOT A,16                       
SHOT A,16                       
Line 90: Line 93:


This parameter determines if the system writes in 2 deflector mode or 1 deflector mode. In 2 deflector mode the primary deflector positions the beam within the main writing field with the subdeflector positions the beam with each 4 x 4 µm subfield. Writing speed is significantly higher in 2 deflector mode and the system should always be used in mode 2.
This parameter determines if the system writes in 2 deflector mode or 1 deflector mode. In 2 deflector mode the primary deflector positions the beam within the main writing field with the subdeflector positions the beam with each 4 x 4 µm subfield. Writing speed is significantly higher in 2 deflector mode and the system should always be used in mode 2.
'''FFOCUS'''
Field Focus was added to the system in 2021. It allows the system to adjust beam focus individually for each writing field based on a sample surface height map generated with HEIMAP. If FFOCUS is omitted the HEIMAP matrix will be used to calculated a single average sample height and beam focus will be set to this value. If FFOCUS is used the HEIMAP data will be used to generate a surface map and each individual writing field will be exposed with a beam focus based on this surface map. This function can not be used with height data obtained from SETWFR or CHIPAL.


'''RESIST [dose]'''
'''RESIST [dose]'''
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Also notice that if an array element is assigned several times, it is the last assignment that will be used.
Also notice that if an array element is assigned several times, it is the last assignment that will be used.


The ASSIGN command can be used to build arrays of arrays to a depth of 9 sub arrays. For examples of sub arrays please refer to our specific page on the ASSIGN command.
The ASSIGN command can be used to build arrays of arrays to a depth of 9 sub arrays.


'''SKIP (j,k)'''
'''SKIP (j,k)'''
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The JDF is terminated with a END command.
The JDF is terminated with a END command.


=Alignment exposure - direct exposure mode=
=Alignment exposure=
As described in the pattern preparation section there is two different strategies for pattern alignment. One can expose a wafer scale layout based on two global alignment marks or one can do chip exposures where each chip is individually aligned to an individual chip mark, as illustrated below. In both cases the SDF and JDF files have to be expanded with additional features to call and define the alignment procedure. Below is two examples, one for global alignment and one for chip alignment. Only new commands relative to the above example will be commented.
As described in the pattern preparation section there is two different strategies for pattern alignment. One can expose a wafer scale layout based on two global alignment marks or one can do chip exposures where each chip is individually aligned to an individual chip mark, as illustrated below. In both cases the SDF and JDF files have to be expanded with additional features to call and define the alignment procedure. Below is two examples, one for global alignment and one for chip alignment. Only new commands relative to the above example will be commented.


Line 225: Line 232:
|-  
|-  
| colspan="1" style="text-align:center;|
| colspan="1" style="text-align:center;|
Illustration of wafer scale pattern alignment and chip array alignment for two designs, L1 and L2.
Illustration of wafer scale pattern alignment and chip array alignment for two designs, L1 and L2. The goal is to align the L2 pattern to the L1 pattern.  
|}
|}


==Global alignment - schedule file==
==Global alignment==
The following file has additional features for global alignment.
The following files set up a single pattern for exposure with global alignment. To execute global alignment a few extra commands are used compared to the previous example. Only new commands are explained below.


===Global alignment SDF===
<pre>
<pre>
MAGAZIN    'THOPE'
MAGAZIN    'ELELOP'


#8                             
#8                             
% 4A                         
% 4A                         
JDF    '21031L2',1
JDF    'elelop230401',1
ACC 100                         
ACC 100                         
CALPRM '6na_ap5'     
CALPRM '6na_ap5'     
Line 243: Line 251:
GLMDET A
GLMDET A
CHIPAL 0
CHIPAL 0
HSWITCH OFF,OFF
HSWITCH ON,OFF


RESIST 152                   
RESIST 152                   
SHOT A,32                   
SHOT A,32                   
OFFSET(0,0)                   
OFFSET(-150,233)                   


END 8
END 8
</pre>
</pre>


Compared to the first print exposure the SDF file has three extra commands, '''GLMDET''', '''CHIPAL''' and '''HSWITCH'''.
Compared to the first print exposure the SDF file has three extra commands, '''GLMDET''', '''CHIPAL''' and '''HSWITCH'''. Additionally, the '''OFFSET''' command serves a somewhat different purpose now as explained below.
 
'''GLMDET [mode]'''
 
'''GLMDET''' (GLobal Mark DETect) has four modes
 
*A - for automatic alignment
*S - for semi automatic alignment
*M - for manual alignment
*C - for cancel, i.e. no alignment
 
In automatic mode the system will execute the '''SETWFR''' subprogram to find the global alignment marks (P and Q) by beam scans. '''SETWFR''' will execute mark detection at the P and Q mark locations defined in the JDF file. If alignment fails the system will continue to the next sequence in the SDF file. In semi automatic mode the system will carry out the same alignment procedure as automatic mode but if the mark scan fails the system will ask the user to use SEM mode to manually find the mark. When the mark is found in SEM mode the user can choose to designate the position as the true mark position or request another beam scan at the found location. Thus, semi automatic is somewhat more versatile at it allows the user to manually find the mark upon failure. Manual alignment allows the user to use SEM mode and manually find and identify the location of the center of the mark. Cancel mode skips global alignment. In the example above automatic alignment is used.
 
 
'''CHIPAL [mode]'''
 
'''CHIPAL''' has six modes and is explained in the section below on chip alignment. Even though chip alignment is not used during global alignment it is necessary to include the command and set it to either 0, V1 or V4, as explained below. In the example above '''CHIPAL''' is disregarded by setting it to 0.
 
 
'''HSWITCH [swg,swc]'''
 
'''HSWITHC''' specifies the substrate height detection mode for aligned exposure. It takes two parameters '''swg''' and '''swc''' which are merely two ON/OFF switches for global mark and chip marks, respectively. If '''swg''' is set to ON the system will carry out substrate height measurement at the global mark positions. If '''swc''' is set to ON the system will carry out substrate height measurement at the chip mark positions. Thus this is a convenient way to have the system measure substrate height and adjust beam focus to chip placement positions. In the example above the global mark positions are used for height detection of the substrate.
 
 
'''OFFSET[x,y]'''
 
For aligned exposures the '''OFFSET''' command must be used to state the offset of the P mark as determined by the optical pre-aligner. This offset will be applied to the entire content of the JDF file, i.e. the offset is used to shift the mark scan detection position. In the example above the pre-aligner was used to determine the P mark is shifted -150 µm in x and 233 µm in y relative to the center of the exposure/cassette slot.


==Global alignment - jobdeck file==
===Global alignment JDF===
<pre>
<pre>
JOB/W    'ELELOP',4
JOB/W    'ELELOP',4
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PATH DRF5M
PATH DRF5M
   ARRAY (0,1,0)/(0,1,0) ;
   ARRAY (0,1,0)/(0,1,0) ;
ASSIGN P(1) -> ((*,*),MOD001) ;
ASSIGN P(1) -> (*,*) ;
   AEND
   AEND
PEND
PEND
Line 275: Line 309:
END
END
</pre>
</pre>
The JDF file has two additional commands, '''GLMPOS''' and '''GLMP'''.
'''GLMPOS [P=(x1,y1), Q=(x2,y2)]'''
'''GLMPPOS''' defines the global alignment mark coordinates in the substrate coordinate system and hence where '''SETWFR''' will perform beam scans for mark detection, unit is µm. In the example file the global marks are located at x = ±36000 µm and y = 0.
'''GLMP [w,l,t,f]'''
'''GLMP''' allows the user to add dimension information about the alignment mark and toggle between a cross and an L mark. The first parameter, '''w''', defines the width of the mark, unit is µm. The second parameter, '''l''', defines the length of the mark, unit is µm. For a cross this is the length of a single leg of the cross. The third parameter, '''t''' allows the user to toggle between a cross (0) and an L (1). The last parameter, '''f''', defines the rotation of the mark in case an L mark is used. It is most advisable to use a cross, i.e. keep the last two parameters at 0. In the example above a 2 µm line width cross with a length of 450 µm is used.
==Chip alignment==
Chip alignment requires a global alignment to be made first to establish the wafer coordinate system. Hence a global alignment using '''GLMDET''' is used initially as in the example above. To further illustrate chip alignment we will look at a particular layout shown below. The layout also illustrates a commonly used feature on the JEOL system to create arrays of arrays. In the layout below there is main 2x2 array and into each of these is a 5x5 subarray. Each element of the subarray is a single chip with four chip alignment marks. Notice that array placement is given in the substrate coordinate system and so is the global mark positions. Chip alignment marks (M1-M4) are however given in the local chip coordinate system. In the example files below we assume L1 is already defined on the substrate and we wish to align L2 to it.
Since a pattern (V30 file) is placed at the center of the bounding box it is essential to control the bounding box of the chip design. The design in this case appears symmetric around (0,0) but in order to force it to be symmetric it is common to place corner marks at equidistance points from (0,0). The corner marks can be 1 nm boxes that will not show up in the resist when developed.
{| style="border: none; border-spacing: 0; margin: 1em auto; text-align: center;"
|-
| [[image:EBLChipAlignExample.png|1200px]]
|-
| colspan="1" style="text-align:center;|
Illustration of chip alignment using a chip array instanced into another array. Notice in the right most illustration how four corner marks are used to force symmetry around (0,0) such that the pattern is placed correctly.
|}
===Chip alignment SDF ===
<pre>
MAGAZIN 'THOPE'
#8
%4C   
JDF 'thope230126',1
ACC 100
CALPRM '6na_ap5'
DEFMODE 2     
GLMDET S
CHIPAL 1
HSWITCH OFF,ON
RESIST 250
SHOT A,6
OFFSET(-44,-139)
END 8
</pre>
'''CHIPAL [mode]'''
'''CHIPAL''' has six modes
*0 - Cancels chip alignment
*S - SEM mode. The user is prompted to use SEM mode to manually find M1
*1 - One mark is used for position correction
*4 - Four marks are used for position, rotation and gain correction
*V1 - Virtual mode 1. A single mark position is used for height detection of the substrate, no position correction
*V4 - Virtual mode 4. Four mark positions are used for height detection of the substrate, no position correction
In addition to position correction mode 1 and 4 also detects substrate height. The virtual modes are only used to detect substrate height since no mark detection is done. Mode S obviously very time consuming for a high number of chips.
If set up properly on good quality marks mode 1 or mode 4 chip alignment can usually execute in about 1-2 seconds per mark. The time estimate at compilation will account for the time spend on chip alignment at the current settings of the '''CHIPAL''' subprogram.
===Chip alignment JDF ===
In addition to the use of '''CHMPOS''' for chip mark position definition the example below illustrate making arrays of an array. The first array is set up as a 2x2 array assigning array '''A1'''. '''A1''' is defined below as '''1:''', since '''1''' is defined as an array it can be referenced as '''A1'''. '''A''' then defines a 5x5 array assigning pattern '''P(1)''' to each element. The chip mark position command must be used in the same array that assigns the corresponding pattern.
<pre>
JOB/W    'THOPE',4  ; 4inch wafer
GLMPOS    P=(-30000,0),Q=(30000,0)
PATH FT01
  ARRAY (-15000,2,30000)/(10000,2,20000)
ASSIGN A(1) -> ((1,1))
1: ARRAY (-4000,5,2000)/(4000,5,2000)
CHMPOS M1=(-450,450),M2=(450,450),M3=(450,-450),M4=(-450,-450)
ASSIGN P(1) -> (*,*)
  AEND
PEND
LAYER 1
        P(1)  'thope230126.v30'
        SPPRM 4.0,,,,1.0,1
        STDCUR  6
END
</pre>
'''CHMPOS [M1=(x1,y1){,M2=(x2,y2),M3=(x3,y3),M4=(x4,y4)}]'''
'''CHMPOS''' defines the chip alignment marks in the local chip coordinate system, unit is µm. M1 is mandatory while M2-M4 are optional in one mark mode. In four mark mode all marks must be defined. The order of the marks is important, M1 must be top left with M2-M4 placed clockwise around the center. In the given example the four marks are placed symmetrically at ±450 µm in x and ±450 µm in y.
It V1 mode it is customary to set M1 = (0,0) such that substrate height is detected at the center of the chip. In this way V1 mode can be used to exactly read out substrate height where the chip pattern will be written.
=Beam current and condition files=
The beam current can in principle be changed in very fine steps, it however requires recalibration of the Dynamic Focus and Dynamic Stigmation table. Hence, only a limited number of beam currents are available. The available beam currents and condition file name are listed below.
{| class="wikitable"
|+  Condition files and beam current
|-
! Beam current [nA] !! Aperture !! Condition file
|-
| 0.12 || 4 || 0.12na_ap4
|-
| 0.16 || 4 || 0.16na_ap4
|-
| 0.22 || 4 || 0.22na_ap4
|-
| 0.4 || 4 || 0.4na_ap4
|-
| 0.5 || 4 || 0.5na_ap4
|-
| 0.8 || 4 || 0.8na_ap4
|-
| 1.4 || 4 || 1.4na_ap4
|-
| 1.6 || 4 || 1.6na_ap4
|-
| 2 || 4 || 2na_ap4
|-
| 2.7 || 4 || 2.7na_ap4
|-
| 3.8 || 5 || 3.8na_ap5
|-
| 4 || 4 || 4na_ap4
|-
| 5 || 5 || 5na_ap5
|-
| 6 || 5 || 6na_ap5
|-
| 10 || 6 || 10na_ap6
|-
| 12 || 5 || 12na_ap5
|-
| 14 || 8 || 14na_ap8
|-
| 19 || 7 || 19na_ap7
|-
| 21 || 7 || 21na_ap7
|-
| 22 || 7 || 22na_ap7
|-
| 25 || 7 || 25na_ap7
|-
| 27 || 7 || 27na_ap7
|-
| 29 || 7 || 29na_ap7
|-
| 30 || 8 || 30na_ap8
|-
| 36 || 8 || 36na_ap8
|-
| 41 || 8 || 41na_ap8
|-
| 44 || 8 || 44na_ap8
|-
| 54 || 7 || 54na_ap7
|-
| 60 || 8 || 60na_ap8
|}
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