Open Access Short Research Article

Die Attach Assembly Process Tool Advancement

Frederick Ray Gomez, Rennier Rodriguez, Nerie Gomez

Journal of Engineering Research and Reports, Page 46-49
DOI: 10.9734/jerr/2020/v10i117031

Die attach film (DAF) voids detection is one of the challenges during the introduction of non-conductive adhesives for integrated circuit products affecting production control robustness and detection. In this paper, a specialized tool capable to distinguish and quantify the amount of DAF voids is presented wherein the implementation of semi-auto grid lines generates more precise measurement and correct defect call-out. The tool is proposed as an alternative option for x-ray inspection that is found to be incapable in proper detection and accurate measurement of gaps and un-occupied area within the adhesive thickness that produces over estimation of production rejects.

Open Access Original Research Article

Spruce Woodmeal for Newsprint Applications: A Handsheet Study

Klaus Dölle, Sandro Zier

Journal of Engineering Research and Reports, Page 1-14
DOI: 10.9734/jerr/2020/v10i117027

This study shows that spruce woodmeal can be an alternative cellulosic-based wood additive               for newsprint applications. This study used unbleached wood flour produced from Spruce  sawdust, ground and sieved to a particle size of 20-40 µm, 40-70 µm, 70-120 µm and 200-500        µm.

Woodmeal was added at levels of 2%, 4%, 6%, 8% and 10% based on oven dry fiber content. The basis weight of the newsprint handsheet manufactured was 80 g/m². The study revealed the following outcomes:

Woodmeal with a particle size distribution of 20-40 µm had the highest density followed by woodmeal with 70–150 µm, 40-70 µm, and 200-500µm. Increasing the woodmeal amount resulted in higher porosity. Woodmeal with a particle size distribution of 20-40 µm gave the lowest porosity and a particle size of 40-70 µm gave the highest porosity.

The Tensile index and burst index show decreasing values for the addition of all woodmeals and particle sizes. Woodmeal with strength additive and a particle size of 20 – 40 µm outperforms the other woodmeal types at additions of 2%, 4%, 6% and 8%. For woodmeal with a particle size of 70–150 µm at an addition of 2% and 4% an increased and similar burst index resulted for the handsheets.

First pass retention and ash retention increased for all wood flours with a maximum at 92% and 81% respectively for the wood flour with a particle size of 40-70 µm.

Open Access Original Research Article

Behavior of Foundations on Reinforced Sabkha Soil: A Numerical Study

Lamia Sadek, Khaled M. M. Bahloul

Journal of Engineering Research and Reports, Page 15-23
DOI: 10.9734/jerr/2020/v10i117028

The aim of this research is to investigate numerically the behavior of strip footings resting on Sabkha soil reinforced using two methods. Firstly, using a layer of compacted sand reinforced with random distributed fibers beneath footing. Secondly, using a layer of compacted sand reinforced with geogrids.

The benefit of mentioned two methods on the improvement of strip footings bearing capacity and decreasing the settlement was investigated using a finite element computer program Plaxis 2D ver. 8.6. It was found that using two methods increases bearing capacity of strip footings significantly specially using first method (fiber reinforced sand layer). It was observed also that the settlement decreased for the same stress values.

Open Access Original Research Article

Laser DAF Cut Augmentation for Thin Wafers

Bryan Christian Bacquian, Frederick Ray Gomez

Journal of Engineering Research and Reports, Page 24-31
DOI: 10.9734/jerr/2020/v10i117029

The semiconductor industry is becoming more inclined to thinner integrated circuit (IC) packages. Thinner packages with thin wafer or die prefer the die attach film (DAF) technology as the die adhesive material solution. As the wafer goes thinner, it becomes more of a challenge in process development, especially during its assembly preparatory stages. As the dies become smaller and thinner, wafer sawing process should have minimum effect on the mechanical integrity of the silicon so as not to alter its quality.

New technologies were developed and introduced in the industry and one of this is the laser die attach film (DAF) cutting. The method was developed together with dies before grinding (DBG) as a cutting medium to address potential processability problems that may occur on the conventional mechanical blade saw. This paper discusses the laser DAF cut development covering the design of experiments (DOE) to understand the different characteristics of laser DAF solution. Validations are made through actual simulation and wafer processing. The paper also covers the interaction of different DAF thicknesses and parameters in order to define the critical characteristics in achieving optimal DAF cutting process responses.

Open Access Original Research Article

Reservoir Flow Unit Analysis of Akos Field in Niger Delta

G. O. Emujakporue, E. E. Enyenihi

Journal of Engineering Research and Reports, Page 32-45
DOI: 10.9734/jerr/2020/v10i117030

In this study, the flow units of reservoirs of Akos field have been computed with the Stratigraphic Modified Lorenz plot. Cumulative flow capacity and cumulative storage capacity were used for constructing the Stratigraphic Modified Lorenz Plot (SMLP). The flow capacity and storage capacity are functions of calculated permeability and porosity values considering their sampling depth. The porosity and permeability were obtained from composite well logs of eight oil wells in the study area. Two reservoirs A and B were delineated from the well logs. The stratigraphic Modified Lorenz Plots (SMLP) revealed a total of one hundred and twelve (112) Flow units (FU) in the two observed reservoirs A and B. Reservoir A has a total of 53 FU (25 speed zones, 18 baffle zones and 10 barrier zones) and reservoir B has a total of 59 FU (29 speed zones, 16 baffle zones and 14 barrier zones) which cut across all the wells. The flow units in both reservoirs fall within the speed zones, baffles and barrier unit categories. The speed zone units with equal flow and storage capacities are the dominant flow units in both reservoirs. This is an indication that the sediments have good reservoir qualities. The baffle zones have more storage capacity than the speed zones. The barrier zones within the reservoirs are acting as a seal to the flow of fluid.