2.2 Micro manufacture

Question 1

Screen Printing Advantages

Answer 1

⚫ Thick ink film (up to 75μm)
⚫ Wide range of printable
viscosities
⚫ Low printing pressure
⚫ Large format relatively easy
⚫ Flexibility and ease of use
⚫ Industrial scale up

Question 2

Screen Printing Disadvantages

Answer 2

⚫ Thin films difficult
⚫ Resolution (25μm)
⚫ Register
⚫ Interactions between
films in multi layer
printing

Question 3

Ink Jet Advantages

Answer 3

⚫ Master-less
⚫ Dynamic register
⚫ Non contact
⚫ Small sealed volume of liquid
⚫ High material utilization
⚫ Medium resolution
⚫ Features down to 20 μm (typical 50 μm)
⚫ Large scientific knowledge base

Question 4

Ink Jet Disadvantages

Answer 4

⚫ Deposition of droplets
⚫ Thin film
⚫ Flight trajectory
⚫ Production rate – slow
⚫ Speed can be increased at
the expense of resolution
⚫ Careful control of ink properties
and print settings are required
⚫ Limited Rheology window

Question 5

Aerosol Jet Deposition Summary

Answer 5

✓High resolution
▪ Features down to 10 μm
▪ Registration at ±2 microns
✓Direct fabrication from a digital file
▪ No image carrier required
✓Good for prototyping
▪ Rapid evaluation of design and materials
▪ Minimal material usage
✓Transfer is not limited by viscosity or wetting
▪ Can simply dilute to get right viscosity for atomising
▪ Coffee ring effect eliminated – droplets are very small
and evaporate rapidly

X Less suited to mass production
X Comparatively slow but
scalable
X Optimisation is complex
X Large number of process
parameters
X Ink Specific