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LT CIRCUIT CO.,LTD. Company Profile

QC Profile

Materials Catalogue


Rogers RO3001                        RO3003                   RO3006                     RO3010                     RO3210
RO3035                        RO3206                   RO4450                     RO4003C                   RO4350B
RO5880                        RO5870                   RO6010                     RO6002                      RO6006
RO6202                        RO6035                   TMM4                        TMM6                         TMM10
TMM10i                        DiClad 527               RO4725JXR               RO4360
ISOLA Isola FR408HR                                        lsola Getek                                         lsola 620
Isola all chinese factory Type have stock and lsola factory can support in time . lsola Germany factory type need purchasing it .
Arlon Nelco POLYMIDE 35N            POLYMIDE 85N          AD255C                   AD450                         AD450L
POLYMIDE VT-901       F4B                             Nelco 4000N            Nelco 7000N               FR5
Nelco 4000-13              Arlon 25N                   Arlon 25FR               AD300                        AD350
AD10                            AD1000                        AP1000
Taconic TLY-3                             TLY-5                            CER-10                    TLA-34                      TLC-32
TLX-8                            TC350                           TLF-35                      RF30                         RF45
Panasonic Panasonic R775               Panasonic M4                PanasonicM6                         Panasonic M7
Ventec International Group4 VT4B3                            VT4B5                          VT4B7                         VT-47B
Ceramic Ceramic AlN                                 Ceramic AON 99.9%                                 Ceramic ANO 96%
Begquist Begquist 6                                             Begquist 7
TUC&EMC2 TU872                                                    TU682
Others 5G LCP RF705S                                     Kapton


PCB Manufacturing Capabilities


Maximum Number of Layers 32 layers (≥20 layers needs to review)
Max Size of Finish Panel 740*500mm (>600mm needs to review)
Minimum Finished Panel Size 5*5mm
Board Thickness 0.2~6.0mm (<0.2mm, >6mm needs to review)
Bow and Twist 0.2%
Rigid-Flex + HDI 2~12 layers (total layers> or layers of flex>6 needs to review)
Blind and Buried Holes Lamination Press Times Press with same core ≤3times (>3 times needs to review)
Board thickness tolerance (No layer structure requirement) ≤1.0mm, controlled as, ±0.075 mm
≤2.0mm, controlled as: ± 0.13 mm
2.0~3.0mm, controlled as: ± 0.15 mm
≥3.0mm, controlled as: ± 0.2 mm
Min Drill Hole 0.1mm (<0.15mm needs to review)
HDI Min Drill Hole 0.08-0.10mm
Aspect ratio 15:1 (>12:1 needs to review)

Min Space in Inner Layer(one-sided)
4~8L (included): sample: 4 mil; small volume: 4.5 mil
8~12L (included): sample: 5 mil; small volume: 5.5 mil
12~18L (included): sample: 6 mil; small volume: 6.5 mil

Copper Thickness
Inner layer≤ 6 OZ (≥5 OZ for 4L; ≥4OZ for 6L; ≥3OZ for 8L and above shall be reviewed)
Outer layer copper≤ 10 OZ (≥5 OZ needs to review)
Copper in holes≤5OZ (≥1 OZ needs to review)
Reliability Test
Circuit Peel Strength 7.8N/cm
Fire Resistance UL 94 V-0
Ionic Contamination ≤1 (unit:μg/cm2)
Min Insulation Thickness 0.05 mm (only for HOZ base copper)

Impedance Tolerance
±5Ω(<50Ω), ±10%(≥50Ω) needs to review if not this value
Inner Layer Track Width and Space
Base copper (OZ) Track width and space (before compensation), unit: mil
Standard Process Advanced Process
0.3 3/3mil Partial area line tracks 2.5/2.5 mil and have 2.0mil space after
0.5 4/4mil Partial area line tracks 3/3 mil and have 2.5mil space remained after compenstaion
1 5/5mil Partial area line tracks 4/4mil and have 3.5mil space remained after compensation.
2 7/7mil 6/6mil
3 9/9mil 8/8mil
4 11/11mil 10/10mil
5 13/13mil 11/11mil
6 15/15mil 13/13mil
Outer Layer Track Width and Space
Base copper (OZ) Track width and space (before compensation), unit: mil
Standard Process Advanced Process
0.3 4/4 Local tracks 3/3 mil and have 2.5mil space remained after compensation
0.5 5/5 Partial area line tracks 3/3 mil and have 2.5mil space remained after compensation
1 6/6 Partial area line tracks 4/4mil and have 3.5mil space remained after compensation
2 7/7 6/6
3 9/9 8/8
4 11/11 10/10
5 13/13 11/11
6 15/15 13/13
Etching Width and Height
Base copper (OZ) Silkscreen width before compensation (unit:mil)
Silkscreen Width Silkscreen Height
0.3 8 40
0.5 8 40
1 10 40
2 12 50
3 14 60
4 16 70
5 18 80
6 20 90
Space Between Pads and Copper in Outer and Inner layers
Base copper (OZ) Space (mil)
Standard Process Advanced Process
0.3 3 2.4
0.5 3 2.4
1 5 4
2 8 6
3 10 8
4 12 10
5 14 12
6 16 14
Space Between Holes and Tracks in Inner Layer
Base copper (OZ) Standard Process (mil) Advanced Process (mil)
4L 6L 8L ≥10L 4L 6L 8L ≥10L
0.5 5.5 6.5 7.5 8 5 6 6 6.5
1 5.5 6.5 7.5 8 5 6 6 6.5
2 5.5 6.5 7.5 8 5 6 6 6.5
3 5.5 6.5 7.5 8 5 6 6 6.5
4 5.5 6.5 7.5 8 5 6 6 6.5
5 5.5 6.5 7.5 8 5 6 6 6.5
6 5.5 6.5 7.5 8 5 6 6 6.5
Remarks: When it is less than 0.5mil of Advanced Process, the cost will be doubled.
Hole Copper Thickness
Base copper (OZ) Hole copper thickness (mm)
Standard Process Advanced Process Limit
0.33 ≥18 ≥25 ≥35
0.5 ≥18 ≥25 ≥35
1 ≥18 ≥25 ≥35
2 ≥18 ≥25 ≥35
3 ≥18 ≥25 ≥35
4 ≥18 ≥25 ≥35
Hole Size Tolerance
Types Standard Process Advanced Process Remarks
Min hole size Board thickness ≤2.0mm:
Min hole size 0.20mm
Board thickness≤0.8mm:
Min hole size 0.10mm
Special types needs to
Board thickness>2.0mm, Min hole size: aspect ratio≤10 (for drill bit) Board thickness≤1.2mm:
Min hole size: 0.15mm
Max hole size 6.0mm >6.0mm Use milling to enlarge holes
Max board thickness 1-2layers: 6.0mm 6.0mm Pressed lamination
by ourselves
Multilayer: 6.0mm 6.0mm
Hole position tolerance    

Hole size tolerance (mm)
0.00-0.31 0.31-0.8 0.81-1.6
1.61-2.49 2.5-6.0 >6.0
PTH Hole +0.08/-0.02 ±0.08 ±0.08 ±0.08 ±0.08 ±0.15
NPTH Hole ±0.05 ±0.05 ±0.05 ±0.05 ±0.05 ±0.15
PTH Slot Hole size<10mm: tolerance±0.13mm hole size≥10mm:tolerance±0.15mm
NPTH Slot Hole size<10mm: tolerance±0.15mm hole size≥10mm:tolerance± 0.20mm
Pads size
Types Standard Process Advanced Process Remarks
Annular ring of via holes 4mil 3.2mil
1.Compensation shall be made according to the base copper thickness. The copper thickness is increased by 1oz, the annular ring shall be increased by 1mil in compensation.

2.If BGA solder pads<8mil, the board’s base
copper should be less than 1oz.
Annular ring of component hole 7mil 6mil
BGA solder pads 10mil 6-8mil
Mechanical processing (1)
Types Standard Process Advanced Process Remarks
V-cut V-cut line width: 0.3-0.6mm    
Angles: 20/30/45/60 Check with engineer for special angles Need to buy V-cut knife
for special angles
Max size: 400    
Min size:50*80 Min size:50*80  
Registration tolerance: +/-0.2mm Registration tolerance:
1L min board thickness: 0.4mm 1L min board thickness: 0.4mm  
Max board thickness 1.60mm Max board thickness 2.0mm  
Max size 380mm
Min size 50mm
Max size 600mm
Min size 40mm
2L min board thickness 0.6mm 2L min board thickness 0.4mm  
Board edge routed Board thickness: 6.0mm    
Tolerance Max length*width: 500*600 Max length*width:500*1200 only for 1-2L  
L≤100mm:±0.13mm L≤100mm:±0.10mm  
100mm<L≤200mm:±0.2mm 100mm<L≤200mm:±0.13mm  
200mm<L≤300mm:±0.3mm 200mm<L≤300mm:±0.2mm  
L>300mm:±0.4mm L>300mm:±0.2mm  
Space between tracks and board edge Outline routed:0.20mm    
V-cut: 0.40mm    
Countersunk hole +/-0.3mm +/-0.2mm By hand
Half PTH holes Min hole 0.40mm ,space 0.3mm Min hole0.3mm,space 0.2mm 180±40°(Not apply for
gold plating)
Routing stepped hole Max hole size 13mm Min hole size 0.8mm  

Gold finger chamfer angles and tolerance 20°、25°、30°、45°
 LT CIRCUIT CO.,LTD. quality control 0
Gold finger chamfer residual
thickness tolerance
±5 mil
Minimum Angle radius 0.4 mm
Beveling height 35~600 mm


Beveling length


30~360 mm  LT CIRCUIT CO.,LTD. quality control 1


Beveling depth tolerance


±0.25 mm
Slots ±0.15 ±0.13m Gold Finger,Board Edge
  ±0.1(Optronics products) Outsource
Routing inner slots Tolerance ±0.2mm Tolerance±0.15mm  
Conical holes angles Larger hole 82º、90º、120º Diameter ≤6.5 mm(>6.5 mm
need to review)
Stepped holes PTH and NPTH, larger hole angle 130º Diameter ≤10mm need to review  
Back Drilling holes Tolerance ±0.05mm    
Mechanical processing (2)
Min values Min slot width:
CNC rout: 0.8mm
CNC drill: 0.6 mm
CNC rout 0.5mm
CNC drill 0.5mm
Need Purchase
Outline rout knife and positioning dowel Knife diameter: 3.175/Φ0.8/Φ
Knife diameter: Φ0.5mm Need Purchase
Min positioning hole: Φ1.0mm    
Max positioning hole: Φ5.0mm    

V-cut details(as below): 

LT CIRCUIT CO.,LTD. quality control 2


Types Standard Process Advanced Process Remarks
Min board thickness 4L:0.4mm;
For Advanced Process ,only can do
HOZ for inner layer.
Multilayer (4-12) 450x550mm 550x810mm This is the max unit size.
Layers 3-20L >20L  
Lamination thickness tolerance ±8% ±5%  
Inner layer copper thickness 0.5/1/2/3/4/5oz 4/5/6oz should be completed with
self-pressing material or electroplate
to strength the copper thickness.
Inner layer mixed
copper thickness
18/35μm ,35/70μm  
Base Material Types
Types Standard Process Advanced Process Remarks
1-2L Refer to Main Material List 0.06/0.10/0.2mm  
Material Types FR-4    
Rogers all series    
High TG and thick copper   TG170OC, 4OZ
Samsung, TUC   1/2 layer
BT material    
PTFE   All PTFE types
Special Requirements
Types Standard Process Advanced Process Remarks
Blind and Buried Vias Meet Standard Process requirement. For asymmetrically buried
and blind via boards, the bow
and twist can’t be guaranteed within 1%.
Immersion Sn   Outsource  
Immersion silver   Outsource  
Board Edge Plated Single side or double sides, if plated 4 edges, there must have joints.
ENIG+OSP Peelable mask should be more than 2mm on LF HASL boards.And should be more than 1mm on ENIG or OSP boards.
Gold finger+OSP

Special material and process
Coil boards
Must meet Standard Process requirements.
Inner layer hollowed out
Outer layer hollowed out
Rogers series
Free-issued materials
Arlon series
Via in pads  
Special shaped hole/slot Countersunk hole,half hole,stepped hole,depth
slot,board edge plated etc.
Impedance boards +/-10% (≤+/-5% need to review)
FR4+microwave material+metal core Need to review
Partial thick gold Local gold thickness: 40U"
Partial mixed material laminating FR4+Ceramic Filled Hydrocarbon
Partial higher pads Need to review
Surface finish
Surface Plating Thickness (U") Leaded HASL
Lead Free: ENIG, LF HASL, Immersion Sn, Immersion Silver, OSP
Process Surface Min Max Advanced Process
ENIG on whole panel Ni 150 600 1200
Au 1 3 Special requirement could reach 50um
ENIG Ni 80 150 Up to 400um without solder mask
Au 1 5 Need to review for gold thickness 5-20U"
Gold fingers Ni 100 400  
Au 5 30 Up to 50um
Immersion Sn Sn 30 50  
Immersion silver Ag 5 15  
LF HASL Sn 50 400  

Surface Plating Thickness (U")
HASL Sn 50 400 Non RoHS product
OSP Oxidation film 0.2-0.5um  
Thickness On tracks 10-20um Can repeat print several times to increase the thickness
On base material
Will add as per copper thickness
7-15um This is for single legend thickness, could do repeat printing for large size legends.
Peelable mask thickness(um) 500-1000um
Holes Covered by Peelable Mask PTH hole ≤1.6mm Please advice on spec. if it is out of the requirement.
HASL Boards
Board thickness ≤ 0.6mm,do not apply for HASL surface.
Selective Surface Finish ENIG+OSP, ENIG+gold finger, Immersion silver+gold finger,Immersion TIN+gold finger, LF
HASL+gold finger
Plating in Holes
Process Types Min thickness Max thickness Advanced Process
PTH Plating thickness in holes 18-20um 25um 35-50um
Base Copper Thickness Copper thickness of inner and outer layer 0.3/0.5 3 4-6
Finish Copper Thickness Outer layer 1 4 5-8
Inner layer 0.5 3 4-6
Insulation Thickness 0.08 N/A 0.06
Finish Board Thickness Tolerance
Finish Board Thickness Standard Process Advanced Process Remarks
≦1.0mm ±0.10mm    
1.0mm~1.6mm(included) ±0.14mm    
1.6mm~2.0mm(included) ±0.18mm    
2.0mm~2.4mm(included) ±0.22mm    
2.4mm~3.0mm(included) ±0.25mm    
>3.0 ±10%    
Solder Mask
Color Green, matt green, blue, matt blue, black, matt black, yellow, red, and white etc.
Min solder mask bridge width Green 4mil, other colours 4.8mil
Solder Mask Thickness Standard 15-20um Advanced: 35um
Solder Mask Filling Holes 0.1-0.5mm  

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