SII NanoTechnology Inc. will release a new photomask defect repair system in December. The new system "SPR6300", repairs defects on photomasks for semiconductor devices to accommodate the 65-nm node generation and beyond.
This system employs scanning probe microscope (SPM) technology with a diamond probe to repair opaque defects(*1) on a photomask and also makes it possible to remove extremely small foreign substances not so far been sufficiently supported by conventional methods such as focused ion beam (FIB) and laser repair technology.

The photomask is an original plate used in the lithography process for making semiconductor integrated circuits. With the increasing miniaturization of semiconductor devices in recent years, the need for improvement in the photomask production yield has emerged, and the importance of photomask repair technology has increased. With the 65-nm node generation, the size of the defects requiring repair has decreased to the nanometer level, and their shape has become extremely complex due to greater use of OPC patterns(*2) as a result of the development of RET technology(*3). Also, due to the demand for 193-nm ArF lithography(*4), the optical characteristics of the repair location have become extremely strict, requiring a reduction in glass damage to the degree of 10 nm or less. Recently, the expanding utilization of alternating phase shift masks (A-PSMs(*5)) is increasing the need for repairing glass bump defects and edge defects. Additionally, the removal of foreign substances, which has been normally performed using conventional repair technology such as laser technology, is now more difficult due to miniaturization in size.

Since it began research and development in 1982, SII NanoTechnology, as a leading company of focused ion beam technology and scanning probe microscopy, has provided a great number of products based on state-of-the-art technology. To resolve the above-described challenges, SII NanoTechnology applied SPM technology to photomask repair, and the SPR6300 was developed. The SPR6300 offers high-resolution SPM image observation function as a repair system and is capable of physically repairing photomask defects using a newly developed diamond probe in addition to the conventional observation probe.
Due to its superior high-resolution observation capability at the nanometer level and its ability to obtain depth information that cannot be measured with such tools as FIB, SPM enables accurate observation of the defect shape and, as a consequence, high-precision repair. In addition, since transmission deterioration caused by gallium ion injection does not occur, low damage repair -a challenge with FIB photomask repair systems- is also possible.
This system offers high performance imaging capability by combining a carbon nanoprobe with SIS mode(*6), an SII NanoTechnology's proprietary observation mode. High-definition 3D observation in irregular topography such as A-PSM is also possible.

[Features]

1. Achieving a 10 nm or better (3σ) repair accuracy
The new system provides superior observation functionality based on the SPM technology, enabling accurate identification of shape in the direction of depth, which has been difficult to date. Combined with the photomask repair function established in the FIB-based SIR series, the system can achieve a 10 nm or less (3σ) high-precision repairs. The system effectively removes micro foreign substances that were difficult to resolve using a laser or an FIB.

2. Adopting a neutralization system using soft x-ray
The new system employs a soft x-ray neutralization system for charge-up prevention.

3. Automatic cantilever switching function
Because the system is capable of automatic cantilever switching, the processing cantilever and observation cantilever can be easily switched prior to system use.

4. Adopting a rotation stage
The rotation stage eliminates the need for photomask reinsertion, allowing defect repair on patterns in an oblique direction as well.

5. SIR7000FIB linkage repair
The system allows the user to send accurate defect height information obtained from SPR6300 to SIR7000FIB and, based on this information, repair the defect using an FIB. With use of SPM-based defection location and height information, high-precision FIB repair is possible.

[Price]
SPR6300 system 600 million yens

[Product Release]
December 1, 2005

[About SII NanoTechnology Inc.]
SII NanoTechnology Inc., a subsidiary of Seiko Instruments Inc. (SII), is a leading company in the development of advanced, leading edge measurement and analysis instruments. Its head office is located in Tokyo, Japan. It was the first Japanese company to produce SPM and Focused Ion Beam (FIB) Systems. The company's products line-up also includes XRF Analyzers, XRF Coating Thickness Gauges, Thermal Analysis Systems, ICP-OES, ICP-MS and Photomask Repair Systems. Many of these products are utilized to support leading edge research and development. Additional information about the company is available on the Internet at http://www.siint.com/en/