Analysis on the Characteristics of IC Package
To calculate the characteristics of electronic parts is divided by 1.Chip. 2.Assembly, i.e. package. 3. PCB (Printed Circuit Board). Analizing the electrical characteristics of package needs consideration from all system can distinguish the influence of function. Although the analysis method may be change but we can get the characteristics results from the parameters of circuit element (i.e. Resistance, Inductance, Capacitance). Different measurement or modeling technology can prove that the list data is correct.
That moisture in plastic packages can cause cracking or delamination during the surface mount assembly process. During this process, the packages are heated to 220-240¢J. At these temperatures, any moisture present in the plastic vaporizes and exerts stresses in the package, which can cause delamination between the mold compound and the leadframe or die. The mismatch in thermal expansion coefficients of the package¡¦s components also induces stresses. If these combined stresses are greater than the fracture strength of the plastic, cracks will form. The susceptibility of a package to cracking depends on: 1.amount of absorbed moisture, 2.die size, 3.package design, 4.mold compound characteristics, 5.solder reflow temperature profile.
Widely, flip chip technology is defined as mounting the chip to a substrate with any kind of materials and methods, as long as the chip surface (active area) is facing to the substrate. The advantages of FC-BGA is¡G1.Efficient use of PCB area. 2.Area array access for high I/O device. 3.Allow for finer pitches. 4.Fewer joints. 5.Better performance of high frequency application. 6.FC is and will be lowest cost.
Advisor:Ai-Na Hong; Wang-Chuang Kuo; Uerng-Yih Ueng; Cheu-Pyeng Cheng; Wei-Chou Hsu
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:failure flip chip void package delamination moisture electrical crack
Date of Publication:06/22/2001