Multi-Height Precision Alignment With Selectively Developed Alignment Marks

Abstract The objective of this paper is to demonstrate the feasibility of glass mounting substrates made by Laser Induced Deept Etching (LIDE) technology, which include newly developed passive die alignment structures. The aim of these structures is to compensate for potential die misalignments and die shift issues which become severe when moving to panel level fan-out packaging. The passive alignment structures are located at two adjacent edges of the rectangular cavity and are created in the same process step as the open cavities. The filigree spring-like alignment structures benefit from being processed in a crack- and stress-free manner. Although the spring elements have a minimal dimension of less than 100 μm, these structures show an outstanding break strength while deformed when active dies are placed in the mounting cavity. Depending on the design, the spring elements can have a stroke of several tenths of micrometer which enable the compensation of rather large die displacements. Here, we present examples for LIDE-processed mounting glass substrates with the described features. The performance of the proposed design and method was evaluated with a die accuracy study. Test dies with alignment marks were placed in the cavities and measured relatively to alignments marks on the mounting glass substrate. The Fan-Out packaging concept based on the research shown here combines several advantages: due to the relatively high Young's modulus of the glass, the reconstituted wafer shows less warpage than in the state-of-art; while the passive alignment structures reduce the die shift to a minimum (depending on dicing accuracies and through package vias for package-on-package or antenna-in-package application), and can be readily integrated.

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An Alignment Method for Lift-Off on Shallow Grooves in Transparent Substrates for Integrated Dual Grating Structures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.503.447 ◽

2012 ◽

Vol 503 ◽

pp. 447-450

Author(s):

Jin Yang Feng ◽

Feng Chen ◽

Yuan Fang Shang ◽

Xiong Ying Ye

Keyword(s):

Glass Substrate ◽

Metal Layer ◽

Image Contrast ◽

Glass Wafer ◽

Alignment Method ◽

Lift Off ◽

Chromium Films ◽

Different Thickness ◽

Device Property ◽

Alignment Marks

In this Paper, we Propose an Alignment Method for Lift-Off on Shallow Grooves in Transparent Substrates without an Extra Mask. An Assistant Metal Layer Was Deposited on the Glass Substrate with Grooves to Increase the Reflectance, and then a Layer of Photoresist for Lift-Off Process Was Coated and Patterned Aligning with the Shallow Grooves. We Compared the Effect of Aluminum and Chromium Films with Different Thickness as Reflecting Layers. an Aluminum or Chromium Film with the Thickness Larger than 10nm Provides High Enough Image Contrast of Profile of the Alignment Marks Beneath the Photoresist. the Image Contrast of Contour Profile of the Marks Was Enhanced as the Thickness Increased. Lift-Off Process Was then Implemented on the Assistant Reflecting Layer. With a 20nm Cr Layer, we Successfully Did Lithography and Finished the Lift-Off Process to Pattern a Cr/Au Layer on Shallow Grooves in a Glass Wafer. Finally, the Assistant Cr Layer Was Removed Using Dry Etching. the Assistant Metal Layer Has No Undesirable Influence on the Following Process and the Device Property.

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The Functional Relation between Alignment Accuracy and Vertical Separation of Alignment Marks

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/001872087001200610 ◽

1970 ◽

Vol 12 (6) ◽

pp. 599-604 ◽

Cited By ~ 1

Author(s):

Anthony S. Squillace ◽

Ann R. Bien

Keyword(s):

Significant Interaction ◽

Functional Relation ◽

Separation Distance ◽

Alignment Error ◽

Vertical Separation ◽

Ambient Illumination ◽

Third Order ◽

Order Polynomial ◽

Alignment Mark ◽

Alignment Marks

The purpose of this study was to determine the functional relation between alignment error (horizontal offset of two alignment marks) and the vertical separation distance of the alignment marks when the alignment is attempted. This relation was studied with four types of alignment marks and two extreme levels of ambient illumination. The vertical separations ranged from 0.050 to 3.2 in. A significant interaction was found between vertical separation distance and alignment mark design: designs which provided vernier cues were found to be the most effective at greater vertical separation distances. The relation between alignment error and vertical separation can be described by a third-order polynomial.

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Modeling of wafer alignment marks using geometrical theory of diffraction (GTD)

10.1117/12.599252 ◽

2005 ◽

Author(s):

Chin B. Tan ◽

Swee H. Yeo ◽

Andrew Khoh

Keyword(s):

Geometrical Theory ◽

Geometrical Theory Of Diffraction ◽

Alignment Marks

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Bright field alignment marks for optical lithography

Microelectronic Engineering ◽

10.1016/0167-9317(91)90166-b ◽

1991 ◽

Vol 14 (1) ◽

pp. 59-70

Author(s):

U. Ablaβmeier

Keyword(s):

Optical Lithography ◽

Bright Field ◽

Alignment Marks

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The Principle of Formation of Metal-dielectric Micro-sized Metastructures

Rocket-Space Device Engineering and Information Systems ◽

10.30894/issn2409-0239.2020.7.4.97.101 ◽

2020 ◽

Vol 7 (4) ◽

pp. 97-101

Author(s):

A. A. Adzhibekov ◽

◽

A. A. Zhukov ◽

O. A. Alekseev ◽

◽

...

Keyword(s):

Electromagnetic Radiation ◽

High Frequency ◽

Radiation Source ◽

Power Level ◽

Electromagnetic Signal ◽

Dielectric Layers ◽

Numerical Assessment ◽

Deposited Metal ◽

Alignment Marks

The principle of formation of layered metal-dielectric micro-sized metastructures, which are dielectric layers with deposited metal patterns, is proposed. The principle consists in the production of individual layers by photolithographic methods, followed by their assembly and alignment on a special installation using a source of high-frequency electromagnetic radiation with an antisymmetric field. The criterion for the accuracy of the alignment of layers is the power level of the received high-frequency electromagnetic signal at the output of the receiver, which fixes the field of the radiation source, scattered by the metal alignment marks applied to each matched layer. When applying the proposed principle, it is possible to combine optically opaque metaldielectric layers of metastructures, without the use of pins. A numerical assessment of the quality of layer alignment showed that the error of layer alignment when using a centimeter wavelength range for field sensing is no more than 3–4 µm.

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