Vapor Deposition Systems

YES-1224P

YES-1224P

Overview
YES-1224P Specs
Process Management Software (option)

YES vapor deposition systems provide total environmental control over the deposition process and accommodate a variety of functionally diverse silanes, for a variety of processes, on a variety of surfaces. 

YES works collaboratively with Brigham Young University, Department of Chemistry and Biochemistry to develop and prove processes using the YES-1224P.  Read more about the collaboration here.

YES-1224P gives process engineers control over:

• Amount of liquid
• Speed of liquid injection
• Vaporization chamber temperature
• Vapor line temperature
• Process vacuum chamber temperature
• Process starting pressure
• Exposure time
• Surface preparation

Common Applications

• Surface modification to prevent or promote adhesion
• Photoresist adhesion for semiconductor wafers
• Silane/substrate adhesion for microarrays (DNA, gene, protein, antibody, tissue)
• MEMS coating to reduce stiction
• BioMEMS and biosensor coating to reduce "drift" in device performance
• Promote biocompatibility between natural and synthetic materials
• Anti-corrosive coating

Vapor Deposition Process

Dehydration followed by silane vapor deposition coating provides a superior silane/substrate bond that is stable after exposure to atmospheric moisture, extending the time available between process steps. Chemical usage for a vapor deposition process is typically less than 1% of the amount needed for wet application processes, significantly reducing waste and chemical costs.

The vapor deposition process begins with vacuum chamber cycle purges to dehydrate the product. The chamber is evacuated to low pressure and refilled with pure nitrogen several times to completely remove water vapor. Nitrogen is preheated, which helps heat the product.

Once cycle purges are finished, the YES-1224P system pumps the chemical directly from the source bottle to the heated vaporization chamber – without exposing the chemical to moisture.

YES-1224P accommodates two chemical source bottles (option for 3) as well as wide variations of vapor pressures among different silanes. Processes are easily programmed using a touch screen operator interface.

Plasma Process

Plasma cleaning prior to silane deposition improves repeatability. Plasma cleaning the process chamber before each run ensures all runs start from the same point. Additionally, plasma prepares the substrate for deposition.

YES Silane Vapor Deposition System Benefits

• Chemical deposition uniformity
• Contact angle control within +/- 3 degrees
• Moisture resistant surface modification
• More time available between process steps
• Hexamethyldisilizane (HMDS)/wafer bonds will last for weeks with no change to surface adhesion
• Promotes Silane/substrate bonds
• Angstrom-level thickness control
• Increased MEMS and bioMEMS reliability
• Reduced chemical usage over wet chemical modification
• Plasma cleaning option (YES-1224P) ensures all runs start from the same point

MEMS Applications

• Wafer Dehydration
• The moisture on the surface of wafers will cause unintended reactions with various deposition steps. These reactions result in unstable surface which degrade over time. Vacuum dehydration provides a clean stable starting surface resulting in superior films.
• Surface Tension Modification
• As devices are made smaller and smaller, static friction (stiction) becomes more and more significant. By modifying the surface tension with a class of fluorinated silanes, the operating life of moving parts in MEMS devices can be significantly lengthened. Conversely, if surfaces need to be bonded together, other silanes can be coated which enhance bonding strengths between unlike materials.

Silylation

The YES-1224P can also be used as a silylation oven. This process enables the use of short wavelength radiation—with its attendant shallow depth of field—to define high-resolution photoresist topographies.

The process requires exposure of the photoresist layer using a standard process with a reverse mask of the circuit. The wavelength is used to irradiate the top level of exposed photoresist.

Now, the substrate is moved to the silylation oven to be exposed to HMDS vapor. Indene-carboxylic acid generated where the photoresist was exposed then combines with HMDS vapor, impregnating the shallow surface layer with pure silicon.

In the subsequent oxygen plasma process, this silicon layer forms an effective mask and is converted to silicon dioxide. The plasma removed only the unexposed photoresist, leaving a high resolution profile of the defined circuit.