Hayashi Pure Chemical Ind.,Ltd.


Jul 22, 2013Product information

『Quartz Crystal Etchant』 was newly developed for Quartz Crystal Devices

Product Pure Etch ZE400 Series (For Quartz Crystal Devices)
Grade Number Pure Etch ZE401
Sample Supply Start in July, 2013
Mass Production Saga Plant

HAYASHI PURE CHEMICAL IND.,LTD.(President: Mr. Masakatsu Irie, hereinafter,HAYASHI PURE CHEMICAL) has succeeded to develop Quartz Crystal Etchant for Quartz Crystal Devices. Hayashi Pure Chemical is starting sample supply in July, 2013.

Quartz Crystal is one of piezoelectric materials※1 and quartz crystal devices utilizing its properties are important parts which make frequency of basic function of electric devices. Quartz crystal units, one of the quartz crystal devices are widely used for many kinds of electronic products such as mobile phone and personal computer, etc., because many kinds of frequency are available by its cut angle, thickness and length. In recent years,down sizing and high accuracy of quartz crystal units are required according to the development of electronic appliances.

Now, quartz crystal units are manufactured with photolithography technology, and reverse mesa structure is formed with wet etching process for down sizing and high accuracy.

Hydrogen fluoride (hereunder HF) , mixture of HF and ammonium fluoride (hereunder NH4F) are widely used as etchant for wet etching of quartz crystal.

But these etchants have big difference of etching rate depending on each crystal orientation existing in quartz crystal, and it makes different taper angles of cross section. Furthermore, proceeding etching gives roughness on etched surface and ununiform thickness. Also, chemical damage on mask※2 by etchant makes problem that desirable processing can not be achieved. These problems are the reasons of uneven frequency, and then they are the key issue for down sizing and high accuracy. Therefore, taper angle control, flattening etched surface, uniform thickness, and chemical damage control technology of mask are required in etching process. Hayashi Pure Chemical has developed etchant for quartz crystal with its unique technology which decreases difference of taper angle in cross section, gives flat etched surface, and also gives uniform thickness in etching process. Furthermore, controlling the chemical damage on mask with this etchant is possible.

By using this etchant, decreasing difference of taper angle, flattening etched surface, uniform thickness, and controlling chemical damage on mask are possible without special technique. Then, desirable processing can be possible and simplify the processes.

※1 Piezoelectric Material

Material which generates voltage when its crystal is deformed.

Generating electric current on surface by mechanical force is called piezoelectric phenomena.

Deforming mechanically by giving electric current is called inverse piezoelectric phenomena.

※2 Mask

Film material as resist and metals (Au, Cr, etc) which covers area to be protected in etching process.

◆ Features

Features of this newly developed Quartz Crystal Etchant are as following.

  1. Capable of Etching Quartz Crystal without Chemical Damage on Resist and Metal Film Mask (Au, Cr, etc.)
  2. Capable of Reducing Taper Angle Difference of Cross Section
  3. Flattening Etched Surface Possible
  4. Uniform Thickness Available

◆ Application Example

【Substrate】Quartz Crystal Substrate

Quartz Crystal Substrate

【Chemical Resistance】

Chemical Resistance


【Contact Information for Press】

TEL +81-6-6910-7336 FAX +81-6-6910-7330


Information content is as of press released.
Please note this content may differ from latest information.

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