Development of measurement system for die-pad behavior in IC encapsulation process using Hall elements

Abstract

This paper describes a new method of measuring the die-pad behavior in the integrated circuit (IC) encapsulation process using Hall elements and a permanent magnet. The method enables us to measure the die-pad behavior along both the height and rotational directions during the melt filling and curing process. The measurement results were compared with that of the direct observation of the die-pad behavior using a high speed video camera and the static observation of the cross section of molding products, and the results obtained by Hall elements showed more or less good agreement with those of the other two methods. The experiments were carried out under three kinds of transfer times. The results showed that the die-pad moved more when the transfer time was longer, which suggested that the transfer time affected the die-pad behavior.Index Terms-Die-pad behavior, Hall element, IC encapsulation, in-process measurement, permanent magnet, thermosetting resin, transfer molding.

Influences of molding conditions on die-pad behavior in IC encapsulation process analyzed by Hall element method

“…1. Die-pad tilting along the direction is not shown here because it was small as mentioned in the previous paper [4]. The "Final position" in each graph of Fig.…”

“…In the previous study, we developed the "Hall element method," which measures the dynamic die-pad behavior during the filling process using Hall elements and a permanent magnet, and investigated the validity of the measurement system [4].…”

Observation of Polypropylene (<i>PP</i>) Melt Flow on Macro and Micro Cavities during Filling Phase of Injection Molding

“…A few works had been done on investigating the polymer melt flow inside the mold cavity [3]. The experimental research of polymer melt flow in mold cavity can be classified into: a) Mold with transparent cavity walls b) Short shots c) Pigment as flow marker d) Molded surface characteristic e) Pressure and temperature sensor inside cavity In order to observe the polymer melt flow dynamically inside the cavity, the following requirements can be used [4]:…”

“…A high-speed video camera was used to record the mold filling phenomena of rectangular cavities with different channel geometries and layouts. Sato et al [4] developed a visualization mold with a glass inserted structure which enables observation of the dynamic melt behavior inside the cavity along the thickness direction. The melt front profile and the behavior of the melt front surface were observed using a high speed video system, and analyzed with an image processor.…”