Diamond Wafers

Diamond Wafers

Diamond wafers from PAM-XIAMEN are wafer-scale products that are used to tap the huge potential of diamond materials, such as tribological testing, unique nano-scale processing applications and MEMS development. In the current diamond wafer market, there are three grade diamond wafer, Microelectronics Grade diamond wafer, Thermal Grade diamand wafers and slices and Optical Grade diamond wafers:

1. Microelectronics Grade Diamond Wafer for Wafer Fabrication

The wafers can be done experiment with the remarkable properties of diamond, and the specifications, like performance consistency, bow and thickness, meet those of baseline wafer-level, which can make the diamond wire wafer slicing insert directly into the MEMS foundry process.

The composite substrate prepared by the thin diamond film/heterogeneous substrate not only has the high thermal conductivity performance of diamond, but also reduces the cost of the thick diamond film, which can be directly used for epitaxial substrate of wide band gap semiconductor material and the growth of materials. The heat dissipation factor is directly considered from the epitaxial material itself, which is also a major development direction for semiconductor devices in the future. The semiconductor wafer materials are all developing in the large-size wafers, which requires that the diamond single crystal wafer material must be large size and high quality. At the same time, the excellent heat dissipation performance can make a better performance of the device.

1.1 Specification of Microelectronics Grade Diamond Wafer

No. 1 Polycrystalline Diamond Wafer

Diamond Wafer Polycrystalline Diamond
Growth Method MPCVD
Wafer Thickness 0~500um+/-25um
Wafer Size 1cm*1cm;2inch; custom
Surface Roughness Ra< 1 nm
FWHM (D111) 0.354
Coefficient of Thermal Expansion  1.3×10^-6 K^-1
Thermal conductivity >1000 W/m.K
 
No. 2 Wafer-Scale Diamond Wafer
PAM210525-D
Item Wafer Scale Diamond
Thickness 100um 300um
Growth method MPCVD MPCVD
Size 2 inch 2 inch
Surface roughness of growth surface <1nm Ra <1nm Ra
Warp 50um 30um
FWHM (D111) 0.354 (D111) 0.354 (D111)
Thermal expansion coefficient 1.3 (10-6K-1) 1.3 (10-6K-1)
Thermal conductivity (T.C)

TDTR Detection method

1500±200 W/mK

(13 scans with different spot size)

1500±200 W/mK

(13 scans with different spot size)

Microelectronics Grade Diamond Wafer

 1.2 Manufacturing Flow of Microelectronics Grade Diamond Wafer

Microelectronics Grade Diamond Wafer

1.3 XRD Spectra of  2inch  CVD Diamond Wafer

The primary crystal facets orientation of CVD diamond films is (111) plane.

CVD diamond films is (111)

1.4  Raman  Spectra of  2inch  CVD  Diamond Wafer

There is only one single diamond peak at 1333.48 cm-1.

diamond wafer

1.5 SEM Micrographs( × 1k) of the 2-inch Diamond Wafer after Rough Polishing

diamond Wafer

1.6 AFM Micrographs of the 2-inch Diamond Wafer after Rough Polishing

Image Ra = 137 nm with the scanning area of 5×5 μm2.

diamond wafer

1.7 SEM Micrographs(× 1k) of the 2-inch Polycrystalline Diamond Wafer after Finishing Polishing

diamond wafer

1.8 AFM Micrographs of the 2-inch Diamond Wafer after Finishing Polishing

Image Ra = 0.278 nm with the scanning area of5×5 μm2.

diamond wafer

Image Ra = 0.466 nm with the scanning area of 15×15 μm2.

diamond wafer

1.9 EDS Results for Polished Films

The content of elements on the polished area is all carbon. No metal contamination from the polishing plate.

Diamand Wafers

1.10 XPS Results for Polished Films

Diamand Wafers

2. Thermal Grade Diamand Wafers and Slices

Diamond exhibits the highest thermal conductivity among all materials. Its thermal conductivity is up to 2000 W/mK which is higher a lot than that of copper. Therefore, diamond wire cut wafer and slice become more and more popular in thermal management as heatspreaders, heatsinks, lithographically patterned metallization, electrical isolation between top and bottom metallization, stress relieving slits for stress free mounting etc.

CVD diamond heat spreaders in various shapes,and the typical parameters are as follows:

Item Value
Diameter 80mm, or small size such as 5*5mm2
Available Thickness 0.3mm
Thickness tolerance ﹢/-0.02mm
Process DC Arc Plasma
Structure Polycrystalline
Chemical composition 100% C
Density 3.52 g/cm³
Poisson’s ratio 0.1
Young’s modulus 1000-1100 Gpa
Thermal conductivity C>1,000 W/m.K, B>1300W/m.K,A>1800W/m.K
Tensile strength >350 kg/mm²
Vickers Hardness 7000~10000 kg/mm²
Compressive strength >110GPa
Thermal stability 800℃
Wear resistance(abrasion ratio) 100,000~200,000
Chemical Stability Insoluble in alkali and acid
Surface finish polished <50 nm
Surface finish lapped <0.5 um

3. Optical Grade Diamond Wafer

Optical grade diamond wafers are used as window for infrared beam splitters, lenses for terahertz spectroscopy and CO2 laser surgery, Brewster Windows for multi-spectral applications such as free electron lasers, multi-wavelength IR lasers or terahertz optical systems, for Units attenuated total reflection) spectroscopy, for diamond Liquid Cells. Below is the datasheet of the diamond wafer in optical level for your reference:

Parameter Optical Grade Diamond Wafer
Size (3~50)±1 mm
Thickness (100~600)±30 um
Surface Process Polished both sides
Roughness A<5 nm B<10 nm C<30 nm

 

Following diagram shows the optical grade diamond substrate transmission rate:

Transmission Rate of Diamond Wafer

Transmission Rate of Diamond Wafer

Source:PAM-XIAMEN

Diamond Heat Sink

powerwaywafer

 

 

 

 

 

For more information,  please contact us email at  victorchan@powerwaywafer.com  and  powerwaymaterial@gmail.com

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