Sep 27, 2020 · Polyimide (PI) and Polybenzoxazole (PBO) products are typically used as a stress relief and protective insulating layer before packaging or redistribution layer (RDL). PI and PBO plays a critical role in advanced microelectronic packaging as an insulating material and can be processed as a standard photolithography process.

Jan 1, 2017 · In this paper, we will report on our novel low temperature (<200C) curable PBO and PI. A novel alkaline positive tone PBO was developed by re-designing key components of the formulation to enhance lithographic performance, Cu adhesion and chemical resistance.

May 8, 2017 · This post will describe the use of a photosensitive positive-tone dielectric based on polybenzoxazole (PBO) used as the redistribution layers (RDL) in Fan-Out Wafer Level Packaging (FOWLP).

Apr 24, 2017 · The first step in the RDL process is to apply the photoresist to the reconstituted wafer using spin coating (easy to spin coat since the reconstituted wafer is circular). In Figure 3, HD Microsystems HD-8940 is a positive tone photoresist using a low temperature curing polybenzoxazole (PBO).

However, it appears that PBO, with its high drop-reliability properties, is an appealing choice for thick RDL layers in a thickness range above >10um. Moreover, it has been demonstrated that warpage and stress are greatly reduced with PBO, especially for bigger wafer sizes (300 mm).

It is well known that dielectrics based on PI and PBO technologies are widely used as RDL in fan‐in wafer‐level packaging (WLP), flip‐chip chip‐scale packaging (FCCSP), and other applications to relocate I/O connections and reduce stress as well as allowing die stacking.

Apr 19, 2019 · It is well known that dielectrics based on PI and PBO technologies are widely used as RDL in fan‐in wafer‐level packaging (WLP), flip‐chip chip‐scale packaging (FCCSP), and other applications to...

New PI/PBO formed strong network even cured at low temp.. cured film thickness: 10 μm. New PI showed high resolution (7 μm L/S) with smooth pattern profile. shrinkage than conventional PI. a) Cure time: 1 h. New PI showed high elongation regardless of curing temperature. Especially, New PI showed > 50 % elongation even cured at 175 oC.

A new PBO has been introduced which has a curing temperature below 250°C. The material properties have been compared to other high performance polymers and haveshown superior properties with respect to the low curing temperature. A test chip has been redistributed with this low temperature PBO.

Jun 25, 2020 · In this paper, CPI (chip-package interaction) reliability of WLP (wafer level package) was investigated. PBO (Polybenzoxazole)-based RDL (redistribution layer) structure was the primary focus. Firstly, the stress distribution for PBO structures was studied by simulation.