FINDING DICING PLANS FOR MULTIPLE PROJECT WAFERS FABRICATED WITH SHUTTLE MASK

2008 ◽  
Vol 17 (01) ◽  
pp. 15-31
Author(s):  
MENG-CHIOU WU ◽  
RUNG-BIN LIN

Multiple project wafers (MPWs) containing different chip designs from many customers serves as an important vehicle for gaining access to advanced semiconductor process technology for prototyping innovative designs or low-volume production. In this paper, a comprehensive study on the methods for determining dicing plans for MPW was carried out. Dicing plans can be used to determine the number of MPWs needed to be fabricated before chip fabrication and employed to saw the wafers after fabrication. Several methods based on integer linear programming formulation and a heuristic based on simulated annealing was proposed. Through conducting experiments with industrial test cases, these proposed methods can achieve up to 50% wafer reduction in some cases and on average 18% and 38% reduction for low- and high-volume production, respectively. This study makes a contribution to MPW dicing and is also instrumental in developing better reticle floorplanning methods.

2011 ◽  
Vol 31 (1) ◽  
Author(s):  
Walter Michaeli ◽  
Jan Wessels ◽  
Marco Pöhler ◽  
Lionel Winkelmann

Abstract Despite their outstanding properties, the use of composites is still limited. The absence of an appropriate and economic high volume production technology is the most important restriction for the use of composites. This paper presents results of the research on new high volume production chains for continuous fibre reinforced composites which are based on the separation and parallelisation of the process steps “impregnation” and “forming and curing”. Two new impregnation processes for polyurethane and epoxy resin as well as a new compression moulding technology are introduced. The production of high performance parts with a fibre volume content higher than 50% in a cycle time below 10 min is described and analyses of the impregnation quality and the mechanical properties of the parts are presented.


Author(s):  
C D Rudd ◽  
K N Kendall

The last decade has seen strong interest from high-volume manufacturers such as the automotive industry in the development of processes which provide cost effective routes to the manufacture of components in fibre-reinforced composite materials. This paper considers one family of processes that have been targeted as offering a solution—that of resin transfer moulding (RTM)—and reviews the findings of work based at the University of Nottingham. The mechanisms involved are examined together with the variants on the basic process and the implications for high-volume production. Consideration is given to process technology, materials and the relationship between design and manufacture. A route to high-volume manufacture based upon computer aided engineering is proposed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jort Hammer ◽  
Hidenori Matsukami ◽  
Satoshi Endo

AbstractChlorinated Paraffins (CPs) are high volume production chemicals and have been found in various organisms including humans and in environmental samples from remote regions. It is thus of great importance to understand the physical–chemical properties of CPs. In this study, gas chromatographic (GC) retention indexes (RIs) of 25 CP congeners were measured on various polar and nonpolar columns to investigate the relationships between the molecular structure and the partition properties. Retention measurements show that analytical standards of individual CPs often contain several stereoisomers. RI values show that chlorination pattern have a large influence on the polarity of CPs. Single Cl substitutions (–CHCl–, –CH2Cl) generally increase polarity of CPs. However, many consecutive –CHCl– units (e.g., 1,2,3,4,5,6-C11Cl6) increase polarity less than expected from the total number of –CHCl– units. Polyparameter linear free energy relationship descriptors show that polarity difference between CP congeners can be explained by the H-bond donating properties of CPs. RI values of CP congeners were predicted using the quantum chemically based prediction tool COSMOthermX. Predicted RI values correlate well with the experimental data (R2, 0.975–0.995), indicating that COSMOthermX can be used to accurately predict the retention of CP congeners on GC columns.


1986 ◽  
Vol 67 ◽  
Author(s):  
Chris R. Ito ◽  
M. Feng ◽  
V. K. Eu ◽  
H. B. Kim

ABSTRACTA high-volume epitaxial reactor has been used to investigate the feasibility for the production growth of GaAs on silicon substrates. The reactor is a customized system which has a maximum capacity of 39 three-inch diameter wafers and can accommodate substrates as large as eight inches in diameter. The MOCVD material growth technique was used to grow GaAs directly on p-type, (100) silicon substrates, three and five inches in diameter. The GaAs surfaces were textured with antiphase boundaries. Double-cyrstal rocking curve measurements showed single-cyrstal GaAs with an average FWHMof 520 arc seconds measured at four points over the wafer surface. Within-wafer thickness uniformity was ± 4% with a wafer-to-wafer uniformity of ± 2%. Photoluminescence spectra showed Tour peaks at 1.500, 1.483, 1.464, and 1.440 ev. Schottky diodes were fabricated on the GaAs on silicon material.


2017 ◽  
Vol 52 (3) ◽  
pp. 395-404
Author(s):  
Xiuqi Lyu ◽  
Jun Takahashi ◽  
Yi Wan ◽  
Isamu Ohsawa

Chopped carbon fiber tape-reinforced thermoplastic material is specifically developed for the high-volume production of lightweight automobiles. With excellent design processability and flexibility, the carbon fiber tape-reinforced thermoplastic material is manufactured by compressing large amounts of randomly oriented, pre-impregnated unidirectional tapes in a plane. Therefore, the carbon fiber tape-reinforced thermoplastic material presents transversely isotropic properties. Transverse shear effect along the thickness direction of carbon fiber tape-reinforced thermoplastic beam has a distinct influence on its flexural deformation. Accordingly, the Timoshenko beam theory combined with vibration frequencies was proposed to determine the set of transverse flexural and shear moduli. Meanwhile, the transverse flexural and shear moduli of carbon fiber tape-reinforced thermoplastic beam were finally determined by fitting all the first seven measured and calculated eigenfrequencies with the least squares criterion. In addition, the suggested thickness to length ratio for the 3-point bending test and Euler–Bernoulli model was given.


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