IC carrier board or IC substrate can be understood as a high-end PCB, the main function is to carry the IC as a carrier, and connect the signal between the chip and the printed circuit board with the internal circuit of the IC carrier board.
The IC carrier board is mainly used in smartphones, laptops, tablets, networks, and other light-weight, thin, and advanced-function electronic products in telecommunications, medical, industrial control, aerospace, military, and other fields. Rigid PCB has undergone a series of innovations from multilayer PCB, traditional HDI PCB, SLP (substrate-like board ) to the IC substrate. SLP is just a rigid printed circuit board similar to the IC carrier technology.
From the perspective of the production area. In 2018, China's carrier board companies accounted for less than 5% of the global market, Japanese companies accounted for about 23% of the total, mainly distributed in the high-end carrier board market; Taiwanese companies accounted for about 37% of the total, with a rich product line. The rest are Korean, European, and American companies.
From the perspective of product type, semiconductor test boards are roughly divided into the following four types of PCBs:
Probe Card
In the CP test, it is used to connect the tester and the Pad on the Die, usually as the physical interface of Loadboard, ProbeCard is attached to Loadboard though sockets or other interface circuits in some cases.
Application: Before the wafer is cut, the water quality can be tested by pc to avoid packaging costs caused by bad products.
Load Board
It's a mechanical and circuit interface connecting the test equipment and the device under test. It’s mainly used in the yield test after IC packaging in the back end of semiconductor manufacturing. Through this stage of testing, ICs with poor functions can be eliminated, and subsequent electronic products can be avoided due to defective ICs. According to the test platform, the test load board is divided into 93K series, T2000 series, TUF series, etc.
BIB ( Burn-in board , Aging test board )
ICs that have completed package testing are tested for burn-in under specific conditions and time to verify the reliability of the IC.
Interposer Board: The probe card signal is converted by the interposer intermediary layer so that the probe of the Probe head can receive the signal, and the signal can also be transmitted to the test machine for interpretation.
In this article, we mainly share a load board production case, the manufacturer is PCBONLINE, to take this technical discussion, welcome to comment and forward.
Layers: 38L
Thickness: 6.35mm
Material: TU872SLK
Aspect ratio: 30:1
Resin plug holes, electroplated and filled
Surface Treatment: Full board 30U” + partial OSP
Special: PTH Spigot
Size: 768*570mm
DUT: 0.2mm
PIN-LAM: Multi-layer high-speed FPGA
PTH: High Thickness Ratio Diameter Copper Filling Technology
Some details about this product:
Detail 1: PTH countersunk hole
Detail 2: Hard gold+ partial OSP
Detail 3: Selective hard gold 30U”
Detail 4: Selective hard gold 30U"+OSP
Challenges in the production process.
Because ICs are becoming more sophisticated, more and more functions need to be tested, the number of layers of test boards is getting thicker, and the size is getting smaller. Therefore, the following four aspects need to be strictly controlled:
1.Lamination deviation
2.Ultra-high thickness to diameter radio
3.Lager size resin plughole
4.A variety of selective surface methods
PCBONLINE's current process capability
|
Semiconductor test board capability |
Normal capacity |
Advanced capacity |
Ultimate capacity |
|
Product Size(inches) |
≤18*24 |
20*24 |
21*25 |
|
Minimal DUT Pitch,(mm) |
≥0.65 |
0.5-0.4 |
0.35 |
|
Layers |
28 |
30 - 52 |
52+ |
|
Pressing times |
1 |
2 |
4 |
|
Thickness(mils) |
≤187 |
187-280 |
≥280 |
|
Thickness Tolerance(%) |
≥10 |
7--8 |
5--7 |
|
Flatness |
≥5 |
3 |
2 |
PCBONLINE has rich production experience in the field of Loadboard, we don’t worry about the challenges of difficulty and complex, because we have knowledgeable engineers to solve the problem. There is no minimum order quantity for flexible production methods, and e-commerce directly faces terminal marketing methods to keep prices transparent and reasonable.
