Radius of Rolled-Up Trilayer

ε

1

-0.002

ε

2

0

ε

3

0

d

1

[nm]

10

d

2

[nm]

10

d

3

[nm]

0

Y

1

[GPa]

80

Y

2

[GPa]

80

Y

3

[GPa]

80

ν

1

0.3

ν

2

0.3

ν

3

0.3

Using the principle of a bimetal strip on the nanoscale, rolled-up tubes with equilibrium radius

R

can be fabricated by etching the layer below a prestrained multilayer. Here, we use three layers that are stacked on top of one other, with different eigenstrains

ε

i

, thicknesses

d

i

, Young's modulus

Y

i

, and Poisson's ratio

ν

i

. Assuming mechanical equilibrium of bending forces and moments, the equilibrium radius

R

can be determined.