NNfC Thin Films Update July 2014

DRIE – Chuck changed from 6 inch to 4 inch. Standard etch recipes tuned except for 15.0 um/min recipe needs to be tuned for profile. – LF generator showing high forward power fault. Working on replacing the unit with a spare. RIE and PECVD – Pump Maintenance done on all three systems on July 18, Sputter and eBeam deposition – Sputter2 system down due WindowsXP activation (WindowsXP not supported) – working with Smart Systems to find a solution. – Gold consumption on eBeam. Tool status for the month of July-2014

PECVD DRIE Anelva Sputter

Pooling of users for the month of July Sl No.Date Au thickness deposited in nm. Pooling of users in numbers. 1 2/7/ /7/ /7/ /7/ /7/ /07/ /07/ /07/ /07/ /07/ /07/ Total number of gold deposition done in July: 21 Total number of slots had multiple users: 11 Total number of slots had single users: 10 We were not been able to club multiple users on 10 slots because of the thickness and combination of different materials.

R1=5min S1=5min R2=5min S2=5min 0% of 7KV. 5% of 7KV. 9% of 7KV R1=5min S1=1min R2=5min S2=1min 4% of 7KV. 8% of 7KV 0% of 7KV. Power ramp up hold time and power modified in order to reduce the gold usage At power percentage 9% the rate of deposition will be almost 1 A/s. During Soak2 (300 seconds) almost 30 nm of gold will be evaporated and it gets deposited on the shutter. By reducing the Soak2 duration from 300 seconds to 60 seconds we are saving gold that goes on the shutter. ( Roughly 24 nm gold savings per deposition ~ 8g of gold for 20 deposition runs). BEFORE PRESENT

PECVD silicon carbide development Silicon Carbide film optimization Comparison Study of Oxford SiC recipe and SiC w/ H 2 dilution. FTIR and XPS was done to characterize the films. ElementAtomic % SiC (Oxford) Si51.63 C25.44 SiC with H2 Si44.33 C45.51 Deposited Material Deposition Rate (nm/min) SiC (Oxford)28.7 SiC with H26.1

Further exploration of process space with 2-level 3-variable DOE Dep. Rate and FTIR peak area for SiC/SiH/Si-CHn compared for film quality. FR/Pow/Press Trial no.Conditions H2 Flow Rate (sccm)Power (W) Pressure (mTorr) 1LLL HLL LHL LLH LHH HHL HLH HHH Normalized FTIR Peak area Si-HSi-CHnSi-C E E FTIR spectra recorded for each of the 8 samples and normalized area under Si-C, Si-H and Si-CH n was calculated. SiC “quality” based on maximizing Si-C peak area. Dep. Rate (nm/min)

Power and H2 Flow rate are the main parameters for SiC deposition (in SiH4-starvation regime with H2 dilution). Three runs done varying the power, H 2 flow rate and pressure as shown in the table below: Run no.Power (W)H 2 (sccm)Pressure (mTorr) Deposition rate, Refractive Index and Residual stress were measured. Run no. Deposition Rate (nm/min) Residual stress (GPa) Si/C ratio nk (Compressive) (Compressive) (Compressive) Run 1 with increased SiH 4 flow rate from 5sccm- 10sccm Run no. Deposition Rate (nm/min) Si/C rationk

TOTAL THICKNESS DEPOSITED TILL DATE: 5597 nm

Gold usage as per individual users: Sl no.NAMETHICKNESS (nm) 1Rohith Soman1720 2Marsha Parmar1080 3Aditya Roy Choudhury670 4Tanushree H Choudhury660 5Nagarjun KP510 6Suman Sarkar485 7Manohar Lal475 8Adil Meersha350 9Yasasvi GPR250 10Chandan250 11Parameshwar240 12Ganapathi210 13Shishir Kumar200 14Ankur Goswami180 15Kazi Rafsanjani Amin170 16Dhanya Varghese120 17Shradha Takur115 18Sowmya M S100 19Saloni Chaurasia80 20Abheek70 21Manavendra70 22Vijaya Lakshmi65 23Kranthi60 24Abhishek60 25Chandrashekar S Kambar50 26Vamsi50 27Venkatesh Bharadwaja AD50 28Shiva47 29Sangeeth15 30Deepak Ranjan Nayak5 TOTAL8407 Total thickness deposited as per slots booked : 5597 nm Total thickness deposited for individual users : 8407 nm The difference is : 2810 nm Average gold required to deposit 100 nm is : 1.6 g. Saved around 45 g of gold, by pooling the users. Remaining gold : g