John C. Bean WeCanFigureThisOut.org Podcasts

John C. Bean WeCanFigureThisOut.org openbaar

Meer

show episodes

Artwork

1
Making an Integrated Circuit

John C. Bean - WeCanFigureThisOut.org

7y ago7y ago

Dagelijks+

… continue reading

Artwork

1
How Van de Graaff Generators Work

John C. Bean - WeCanFigureThisOut.org

7y ago7y ago

Dagelijks+

This podcast is drawn from the "Virtual Lab" of WeCanFigureThisOut.org. This Virtual Lab uses 3D virtual reality animations to explain electronics, microelectronics and nanotechnology. This podcast explains how Van de Graaff generators work by using a motor to separate charges.

… continue reading

show series

Artwork

1
Let's go inside an Intel 4004 microprocessor to see an individual transistor 0:13

7y ago0:13

0:13

-

… continue reading

Artwork

1
Do you know how Van de Graaff generators work? Let's turn it on. 0:14

7y ago0:14

0:14

-

… continue reading

Artwork

1
Turn it off and the charge stays on the dome. 0:03

7y ago0:03

0:03

-

… continue reading

Artwork

1
To make this transistor, first oxide then nitride layers are grown 0:11

7y ago0:11

0:11

-

… continue reading

Artwork

1
To understand what is going on, let's look inside. 0:11

7y ago0:11

0:11

-

… continue reading

Artwork

1
A shadow mask then exposes a photographic emulsion 0:12

7y ago0:12

0:12

-

… continue reading

Artwork

1
There is only a motor, powering a pulley, connected to a belt, almost touched by a copper comb. 0:21

7y ago0:21

0:21

-

… continue reading

Artwork

1
Exposed nitride is then etched away 0:07

7y ago0:07

0:07

-

… continue reading

Artwork

1
Oxygen reacts with the Si to grow more oxide 0:12

7y ago0:12

0:12

-

… continue reading

Artwork

1
The pulley is made of a special plastic. Let's fade away all but a few (exaggerated) plastic atoms. 0:15

7y ago0:15

0:15

-

… continue reading

Artwork

1
The pulley's plastic atoms will transfer electrons to the inside of the belt (it's just "static electricity"). 0:16

7y ago0:16

0:16

-

… continue reading

Artwork

1
By heating in silane, polycrystal Si is then grown 0:04

7y ago0:04

0:04

-

… continue reading

Artwork

1
A stripe is exposed in a second photographic emulsion 0:10

7y ago0:10

0:10

-

… continue reading

Artwork

1
The inside of the belt becomes more and more negative. 0:16

7y ago0:16

0:16

-

… continue reading

Artwork

1
Exposed polycrystal Si is etched away leaving the transistor gate 0:09

7y ago0:09

0:09

-

… continue reading

Artwork

1
But now let's go back and figure out what the bottom copper comb does. 0:09

7y ago0:09

0:09

-

… continue reading

Artwork

1
Phosphorus ions then penetrate thin oxide to create the source and drain 0:12

7y ago0:12

0:12

-

… continue reading

Artwork

1
Electrons jump from the comb trying to reach the increasingly positive pulley. 0:14

7y ago0:14

0:14

-

… continue reading

Artwork

1
Heating in oxygen grows an insulating coat on the gate 0:06

7y ago0:06

0:06

-

… continue reading

Artwork

1
But these electrons cannot penetrate the belt and are carried away. 0:11

7y ago0:11

0:11

-

… continue reading

Artwork

1
This is an electron's worst nightmare as both sides of the belt are now negative! 0:19

7y ago0:19

0:19

-

… continue reading

Artwork

1
A third photographic emulsion defines windows above the source and drain 0:10

7y ago0:10

0:10

-

… continue reading

Artwork

1
But as they reach the top, the outer electrons can jump onto a second comb ... 0:18

7y ago0:18

0:18

-

… continue reading

Artwork

1
Openings are then etched in the exposed oxide 0:07

7y ago0:07

0:07

-

… continue reading

Artwork

1
and then spread out on the metal dome. 0:18

7y ago0:18

0:18

-

… continue reading

Artwork

1
Metal is sprayed on to the surface 0:03

7y ago0:03

0:03

-

… continue reading

Artwork

1
A fourth photographic emulsion is patterned 0:10

7y ago0:10

0:10

-

… continue reading

Artwork

1
So the Van de Graaff uses the motor's work pushing electrons upward to build up "electrostatic energy." 0:30

7y ago0:30

0:30

-

… continue reading

Artwork

1
Unwanted metal is etched away completing the transistor 0:09

7y ago0:09

0:09

-

… continue reading

Artwork

1
And finally, here is the circuit symbol for the transistor 0:08

7y ago0:08

0:08

-

… continue reading

Artwork

1
This podcast is drawn from the Virtual Lab presentations of WeCanFigureThisOut.org. The copyrighted material of this site was developed under funding from National Science Foundation CCLI, NIRT, MRSEC ... 0:33

7y ago0:33

0:33

-

… continue reading

Artwork

1
This podcast is drawn from the Virtual Lab presentations of WeCanFigureThisOut.org. The copyrighted material of this site was developed under funding from National Science Foundation CCLI, NIRT, MRSEC ... 0:33

7y ago0:33

0:33

-

… continue reading

Artwork

1
All of the scenes together 4:18

7y ago4:18

4:18

-

… continue reading

Artwork

1
All of the scenes together 3:09

7y ago3:09

3:09

-

… continue reading