:closed_book:Project Tasks

:closed_book:Project Tasks === ###### tags: `Tasks` `Stuff` :::info ### :notebook:Quantify Internal Quantum Efficiency for new Epi ($\eta_i$) > Basically fabricate broad area Fabry-Perot lasers (width >50$\mu$m) > ==$f_r^2 = \frac{1}{4\pi^2}\frac{v_ga}{qV_p}\eta_i(I-I_{th})$== ___ > ***:dart: NEW MASK UPDATE*:** **https://hpe-my.sharepoint.com/:u:/p/stanley_cheung/EdDaxbND8GlHpGeH8pybWEwBuCLMw_F2v7Xfsf1W3gniPA?e=Jdp017** ___ - [x]Review current mask with David for cutback structures: **https://hpe-my.sharepoint.com/:u:/p/stanley_cheung/EexV2njTUM1Om11Q5NOjT8UB5yjSzQUVRdHySGJJoH1BSg?e=Vxy6Oc** - [x]David determined that we need a new mask (4 layers): 1. layer1: p-contact 50um wide: wet etch H2SO4:H2O2:H20 (1:5:15) to InGaP 2. layer2: protection layer for TLM with PR 3. layer3: wedding cake structure to access n-contact (dry or wet etch) 4. layer3: n-contact 50um wide 8/7/2019 ![](https://i.imgur.com/0S20sea.jpg) - [x]Ordered masks from Compugraphics (1st 2 layers ship on 8/20) - [ ]Update fab sheet and revise traveler with David and Chuck: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/EWaOOKI_ic9MvHT8zKfylTcBJgsIs2AyUDfhtqk1pJEKjw?e=c7JTjX** - [x]Finalize pulsed current source (LDP-3840B): **https://www.newport.com/c/pulsed-laser-diode-drivers** - [ ]Fabricate at HP Labs and thin/scribe at Oepic :scissors: - [x]Decided to build separate experimental setup with pulsed current driver - [x]Setup build: Purchase TEC, peltier, thermistor, tube 'scope, camera, rails, etc. - [x]Need a computer for data acquisition (still getting approval from Peter) - [ ]Epi material arrival still up in the air, but we can still use existing FPs to test (need to get some back from Guan-Lin at Berkeley) - (after 1st mask): etch down to InGaP H2SO4:H2O2:H20 (1:5:15) cool down to RT, 30 min. - (after 2nd mask): etch down to InGaP H2SO4:H2O2:H20 (1:5:15) cool down to RT, 30 min. - 4 or 5 lengths for the FP laser cutback ::: :::info ### :notebook:Silicon nitride CWDM AWGs and Lattice Filters > Tape-out from Ligentec (150nm $Si_3N_4$) ___ - :dart: MEASUREMENTS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/ETanrkG0OiNFjpmoIEvUSccBi3bfGhe4jK1xBKAPGFyv5Q?e=cgNWrN** ___ - :dart: LATTICE FILTER DESIGNS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/Ece3f9EvPd9Fqw5nXTEWnEQBnOaYW5uZ668K8hVdPBcK-w?e=QeaNdw** ___ - :dart: AWG DESIGNS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/ESsJjV5vgBROpRJTwKn3JUsBtuSABAZ0y05812V0lUWdsw?e=HKYUwr** ___ - [x]Minor builds to existing setup - [x]Characterize same devices on different dies (7 dies) and obtain some statistics * Flat-top and normal AWG - [x]Plot data from past experiments and analyze - [x]Need to purchase tube 'scope and camera :moneybag::moneybag::moneybag::dollar: - [x]Obtained wafer uniformity map ($\mu_{mean}$=148.2nm, $\sigma$=2.3nm) and CD field map ($\mu_{mean}$=238nm, $\sigma$=13nm) - [x]Characterize passband temperature shift (pm/$^\circ$C) -- **AWG (54 pm/$^\circ$C)** -- **MZI Lattice (17 pm/$^\circ$C)** - [ ]Characterize broadband directional couplers & ~~waveguide losses (maybe difficult--lack of spiral lengths)~~ -- **Waveguide loss = 0.3-0.4 dB/cm** at 1064nm for WG width=1.7um - [x]Literature search for grating couplers and edge couplers: **https://hackmd.io/LKF0NdPrTnmjVlx-QTs7ug?both** ::: :::info ### :notebook:HCG with Au metal assisted mirror > Sims and fab with RAITH ___ - :dart: DESIGNS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/EcElrEudd-9Kr8FdvSaawwgBkMgFPj2nCeN8DwVLWSC_XA?e=11tGZw** ___ - :dart: MEASUREMENTS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/EYOWAfKTfF1Do3vEH1SS-6EBjhPTtOQGixjbQ1J961PQtA?e=xXGALb** ___ - [x]New simulations: :computer: :computer: :computer: 1. GaAs HCG/infinite SiO2 :heavy_check_mark: 2. GaAs HCG/finite SiO2 :heavy_check_mark: 3. GaAs HCG/finite SiO2/Au :heavy_check_mark: 4. oxididzed AlxGa1-xAs/GaAs HCG/infinite SiO2 :heavy_check_mark: 5. Al0.6Ga0.4As/GaAs HCG/air cladding :heavy_check_mark: 6. Al0.6Ga0.4As/GaAs HCG/finite SiO2 :heavy_check_mark: 7. Al0.6Ga0.4As/GaAs HCG/finite SiO2/Au :heavy_check_mark: - [ ]START MAKING MHCG/dielectric/Au sample with RAITH e-beam ASAP!!!! - [ ]CHARACTERIZE!!!! ::: :::info ### :notebook:BTO/ITO plasmonic modulator/ MOS effect > for external VCSEL modulation ___ - :dart: DESIGNS: **https://hpe-my.sharepoint.com/:p:/p/stanley_cheung/EZqOWudcN-RDt3QJYOoUMAwB4m04ID3uW4DpBbznBNEOVg?e=uKu7k5** ___ - [x]Literature search - [x]Perform initial design calculations for $r_{eff}$, $V_\pi L$, $\Gamma_{conf}$, electrode gap, etc. - [x]Calculate ITO complex permittivity from Drude-Lorentz model and translate values to refractive index change and loss vs. wavelength vs. carrier concentration - [ ]Look into implementing models in Lumerical with Drude-Lorentz ```flow st=>start: Start e=>end: End op=>operation: Calculate Drude Lorentz op2=>operation: Calculate confinement factor in 10nm charge accumulation layer op3=>operation: Vary Si3N4/ITO, height, width st->op->op2->op3->e ``` :::