Construction of Prototype

After some discussions regarding the anatomy of the integrated circuit has been discussed between jin yang and mushtak, the construction of the prototype of the integrated circuit has already began.

Items were bought from Vision Art &
3x 1kg Plaster of Paris
1x Uhu Glue
1x Paper Clay
1x Black Spray Can
2x Sand Paper

After that the we started the contruction of the main build of the integrated circuit.


Plaster of Paris (POP) with the mould which is actually a shoe box.


The mixture of POP is inserted into the mould.


The mould for the smaller parts of the Integrated Circuit.


After leaving the POP in the mould for a few hours, the mould is torn apart and this is what we get. The surface was rough so an extra layer was applied and it will be sand papered as well to get the texture that is equilavent to a read Integrated Circuit.


The finish product! Sand paper hasn't been used on it yet. The construction of the prototype will resume tomorrow.

Suprisingly today went pretty smoothly as there were not major setbacks in our construction other than chipped edges and the leakage of POP due to the mould not being airtight. The chipped edges was due to the extra POP that leaked through the mould that breaks the edges away as the mould was removed.

Design Change Request

This is the new Design Change Request that has been approved by Mr.Mushtak.

How it all began. The manufacturing of Integrated Circuit.

The first ever transistor was created by William Shockley, John Bardeen, and Walter Brattain from the Bell Labs at around 1947.

The first ever transistor. Big and ugly.


This is how a wafer filled with transistors look like today.

Now I'll give a brief graphical explanation on how an IC is manufactured.

The integrated circuit is based mostly on pure silicon. Silicon is used as it's wafer which can keep thousands of transistors, resistors, diodes and such. Integrated Circuits are made by the hundreds at once time where a single large slice of silicon of wafer is made and then cut into individual IC Chips. The manufacturing has to be made in a clean room where the air is filtered from dust and foreign particles.

The melting process of a silicon.


Vacuum Chamber

The silicon is kept in a vacuum chamber where it is heated to about 1400C which is it's melting point. As the silicon mets, any impurities in the silicon becomes active. The heating coil is then slowly moved downwards to heat the other parts of the silicon in the chamber. The active impurities will follow the heating coil until it reaches the bottom of the silicon chamber. The bottom of the silicon layer is then sliced off and the rest of the cylindrical ingot is of pure silicon.


The Silicon Slicing Diagram.


Silicon wafer is then polished to perfection.

Now that the silicon wafer is made, it can be modified such as patterning, deposition, and removal to determine the end result of the Integrated Circuit. Since the silicon wafer is so small and the cuttings in the wafer would be microscopic, the design for each layer of the wafer will be prepared in a computer-aided drafting machine, and the image will be made into a mask which will be optically reduced and transferred to the surface of the wafer. There are 2 methods of masking that can be used which is through contact and projection. the contact masking method is usually used when the features are more than 1 micrometer and projection method is used when it's less than 1 micrometer.

The mask are used on an aligner which aligns the mask to the wafer. The mask is then moved into the decided position and brought into contact with the wafer. An ultrviolet light then exposes the unprotected photosensitive material on the wafer surface.

This process is done many times until it satisfies the design which is set by the designer of the particular Integrated Circuit Chip.


The completed Integrated Circuit would look something like this internally.

The final step of the manufacturing process is the encapsulation process. The integrated circuit die is being encpsulated with ceramic, plastic, or epoxy to prevent physical damage or corrosion.


This is how the final product looks like.

Written by : Tan Ken Seong

Referred to:
Semiconductor fabrication, Wikipedia
http://www.madehow.com/Volume-2/Integrated-Circuit.html
Demetrios Papageogiou, Electrical Computer Engineering Department, Northeastern University.

Problems Encountered.

After some serious considerations regarding the current design proposal for the circuit, the team members has decided to drop the design and will soon propose for a Design Change Request. Reasons for the changes are due to the complexity of the circuit and the time contraint faced. This will be explained in detail more in the DCR that will be produced and handed in very soon. Meanwhile, the new product that is to replace the old design has already gone through IC Testing and it has been tested to work already. It uses a NAND Logic Gate to function as a water level detected that will beeep whenever the water level in any compartment reaches a level determined by the user. This is thus trigger an alarm to warn te user that the water level has reached the limit so that the user is able to take immediate action.

NAND Gates basically consist of the combination of AND and NOT Gates which are combined to form a NAND Gate. In lay man terms, It's the opposite result that a user would get operating the AND Gate.

INPUT		OUTPUT
A	B	A NAND B
0	0	1
1	0	1
0	1	1
1	1	0

Source : Wikipedia


Other Pictures

A Trip to Farnell which the group members took.


The list of things that are sold in Farnell. A very thick datasheet book.


Items bought in Ang Electronics Sdn Bhd at Jln Meru, Klang


Tong Jiun and Jin Yang working on our new design product. Soldering.

Final Design Proposal (Dummy IC)

Final Design Proposal (Circuit)

Design Proposal - Dummy IC

Design Proposal
SmartSolutions

Design statement

This enlarged dummy IC will show the rough anatomy of an IC which is easily viewed by the naked eye. Thus, it will provide further information regarding the workings of an IC.

In order for the dummy IC to function as a real IC, a real IC is inserted inside the dummy IC and its legs are connected to the dummy IC with a conductor material. Therefore, whenever current is supplied into the dummy IC, it will conduct the current to the real IC inside the dummy IC and thus will function as if it was a real IC.

*The anatomy of the IC has not been fully researched. Thus, there are no final proposal for the anatomy of the dummy IC.*

Proposed by: Chong Jin Yang Accepted by:

Tan Ken Seong

Lai Tong Jiun

Design Proposal - Circuit

Design Proposal
SmartSolutions

Design statement

There is a fan which is connected to a light sensitive circuit. When there is light coming from a source, the fan will be automatically activated by the integrated circuit. Both the main switch and the photo sensor are directly connected to the AND logic gate in the IC. The fan will activate as long as the main switch is on and the photo sensor detects light. The IC will in turn be connected to the fan.

In terms of application, this device is very useful in offices or buildings. When a person enters an enclosed room and turns on the light, the device will detect light and hence will switch on the cooling fan. When the person leaves the room, he or she will switch off the light. As there is no light source, the device will automatically switch off the fan and thus save energy.

Proposed by: Chong Jin Yang Accepted by:

Tan Ken Seong

Lai Tong Jiun

IC Testing

On the 26th of January, we held our first IC Testing in the EE Lab. We thought that our experiment would only take 30 mins to complete because we were quite confident with our design of the circuit but we were wrong. Many problems occurred during our experiment and our IC Testing took 3 hours instead without even gettin the results wanted. However with the help of Dr.Jaga on our side, he pointed a few errors and gave us guides on how to determine which part is causing the faulty results. Although we didn't get the result we wanted, we've learnt alot from this experiment on how to contruct a circuit. These are the problems that occurred during the experiment.

1. All wires must be properly grounded. This caused a big problem for us as the Logic Gate keeps registering as symbol '1' whether voltage is provided into the input or not. The cause of why problem occured is because the wire was not properly grounded and thus the noise from the ungrounded wire is enough to register the symbol '1' on the IC.

2. The input voltage may not the equal to the output voltage which is required. The fan used is able to run at 5V but does not work anywhere below 5V. Therefore initially when the fan is tested, the fan is able to work but when it is connected to the circuit, it does not function anymore. This problem is discovered after replacing the fan with a small powered LED and using the multimeter it is detected that the voltage value on the output is less than 5V. This is due to the high internal resistance inside the circuit that reduces the output.