An Introduction to crystal and Technical know how for MC molded crystal production

An Introduction to crystal and Technical know how for MC molded crystal production
MC306/146 Basic Overview

Glossary
1. Introduction to crystals - What are crystals? - How to make crystals? - How do crystal oscillators work?2. The Application of crystal oscillators - World Market demand and Breakdown - Where are crystals used? - Advantage of crystals3. Manufacturing process for molded crystals - what is molded crystal? - what are the processes involved?4. Questions and Answer Session.

Introduction to Quartz Crystal
1. Quartz Crystals... What?The quartz crystal is a single crystal of silicon dioxide and used in important electronic components.
Raw manufactured Crystal
Cut crystal ready for production

How to grow Synthetic Quartz Crystals

Growing speedThe growing speed is approximately 0.4 to 0.6mm per day and the growing number of day is from about 40 days to more than 200 days depending on the applications. You will get approximately 1,500 to 2,500kg of high quality synthetic quartz crystals in one growth process.
The ordinary growing temperature is approximately 300 to 400C and the growing pressure is approximately 90 to 145MPa.
Lasca or Seed Crystal(Raw Material Needed)

Crystal Making Apparatus and Material
The synthetic quartz crystal is grown by the hydrothermal method using the pressured container called the autoclave. The crystal is insoluble to most of the solution under the normal temperature and pressure but becomes soluble by the hydrothermal reaction in the high temperature and high pressure
1. Hang the seed crystal in the upper growing area and place the raw material, Lasca, a fragment of the natural quartz crystal
2. By maintaining the temperature in the growing area lower than the solution area, the raw material in a saturated state in the dissolution area will rise to the growing area by the heat conviction provided by the temperature difference.
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2

Simple illustration of Piezoelectricity
Quartz Crystal are very stable and their resonant frequency does not vary much with time or temperature.A crystal depends on the piezo-electric effect to work. This effect converts a mechanical stress in a crystal to a voltage and vice versa. In this way the piezo-electric effect converts the electrical impulses to mechanical stress (or movement) which is subject to the very high Q mechanical resonances of the crystal, and this is in turn linked back into the electrical circuit.

The basic process of a crystal Tuning Fork
Firstly the raw material (synthetic crystal) is sliced and cut from its basic raw form.

The crystal is then cut into several pieces.

Thirdly, the crystal is cut into wafer form before being sent to the next process.
After going through the wafer lapping and polishing process, the water is put through to the next process.After wafer polishing the wafer has to go through photo etching process. Before being shaped into its final shape via PHOTOLITHO technology.

Final product
photolithographyA lithographic technique used to transfer the design of circuit paths onto printed circuit boards as well as the circuit paths and electronic elements of a chip onto a wafer's surface. A photomask is created with the design for each layer of the board or wafer (chip). The board or wafer is coated with a light-sensitive film (photoresist) that is hardened when exposed to light shining through the photomask. The board or wafer is then exposed to an acid bath (wet processing) or hot ions (dry processing), and the unhardened areas are etched away.

Basic structure of a crystal unit.

The Tuning Fork is an important component in a crystal oscillator, we will begin by explaining how does the tuning fork works and how it is made, and then moving to how tuning fork works.

Crystal unit for MC306 (cylinder type)
Mounting of chip to a plug with soldering

Adjusting the frequency of the chip by trimming the end portion with laser beam

Encapsulate plug into a capsule in a heated vaccum chamber.

Frequency and characteristics inspection.

Manufacturing process (SMD Molded Crystal) Unit
A cylinder type crystal is welded on the frame.
The frame with the crystal are molded inside a package of epoxy resin.
V sharp for solder plating and second press, unnecessary resin is eliminated.

The lead terminals are solder-plated
Products name, frequency and lot nos are marked by ink or laser on the mold surface.All lead terminals are then trimmed and formed.
Electrical characteristics/ All oscillators are inspected and taped.

Crystal Oscillators uses
Crystal oscillators are used in a wide variety of electronic products such as PCs and mobile phones. As for automotive applications, crystal oscillators are used in in-vehicle audiovisual equipment, car navigation systems, driving control systems, and safety control systems.

Crystal manufacturers by region
-The global piezoelectric crystal industry is characterized by over 450 companies involved in the industry as manufacturers and suppliers.
-In 2007, Japan has the highest market share of 50%, followed by North America with 20%, Europe with 15%, China with 8%, and the rest of the world with 7%. By 2012, Chinas share will be 11%, positioning it close to Europe with 13% share of the global market.
Asia 58%-Japan 50%NDKEPSON TOYOCOMKyocera Kinsenki-China8%
Rest of the world7%
North America 20%

-FoxConner WinfieldVectron
Europe 15%

Market Distribution

Molded crystal (MC)
MC306
MC 306 PROCESS FLOW

Lot Formation
ECT
Poka Miss
QC
PROCESS FLOW CONTINUED

Crystal Welding
Crystal welding is the process where the crystal is welded onto the lead frame. In this case, the crystal being used for MC306 will be the cylinder form.
Linear Machine
Automated Machine
There are 2 types of Machine in the crystal welding process, Linear (manual) machine and the automated machine.

TFM Process (Incoming)
Incoming Compound Rack
Record Sheet stating date and time released from store
Mould Compound
Compound Preheater

TFM PROCESS (Actual)
Mould After Preheating
Fujiwa Mould Transfer M/C
Before Mould Transfer
After Mould Transfer

After Plating Process
MC405
MC306
MC146

Laser Mark Process
Laser marker M/C
Units ready for marking
Marked Units

TRIMMING & FORMING 2
MESIN TF-2 UNTUK MC 306

TF2 Process
TF2 Machine
Trimmed Crystal Units
End product ready for ECI/ECT
Units on Lead frame ready for trimming

Electrical Characteristic Inspection

Type of REEL :Plastic Reel
TAPING

ECT PROCESS
Crest ECT Machine
Nakamura ECY Machine
Finished Reels ready for QC inspection
Reels are arranged on separate racks

Outgoing and Packed Reels

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Simpan frame contoh tunjuk pada operator MC 306=26 units, MC146=50units, MC 405= 30units